Hi guys,
every winter we do some trips to our house in austria. There`s about 5-8feet of snow, so it`s impossible to reach it with a 4x4 (at least with the ones we can built in germany). So i was looking for a snowmobile, but i didn`t like the prices and the fact that i only can use it in the snow...

Then i found this video:

Personal Tracked Vehicle - YouTube (http://www.youtube.com/watch?v=GRPHT9wm5cI&feature=player_embedded)

I started looking for parts and decided that i want to build something like this. Then i saw this picture:

http://army-uk.com/stock/fotobig/803_bv206-ch5.jpg

I soon decided that i have to built a smaller version of this...

The specs:

It needs to be small enough to fit in the back of my L300. Available space is about 120cm x 270cm. The width will be ok, but the length not. But this won`t be a problem, it`ll just stick out a bit. I think dimensions will be about 120cm x 340cm.

Drivetrain:
I`ll use everything out of a Subaru Justy. Engine, tranny, both axles, radiator, driveshaft, steering, just everything that`s needed. Should have a lot of power with the 75hp engine. :Wow1:

The first quick sketch:

http://www.abload.de/img/dsc06858p5pap.jpg

http://www.abload.de/img/dsc06859e8ox6.jpg

Then i started with the first track, to get some ideas:

http://www.abload.de/img/dsc06864lbp11.jpg

http://www.abload.de/img/dsc0686884ois.jpg

http://www.abload.de/img/dsc068701drey.jpg

http://www.abload.de/img/dsc068729vpb6.jpg

Mockup:

http://www.abload.de/img/dsc068762lq9p.jpg

Then i did a few drawings:

http://up.picr.de/9327434upx.jpg

http://up.picr.de/9327435yvf.jpg

http://up.picr.de/9327436alt.jpg

http://up.picr.de/9327438byi.jpg

http://up.picr.de/9327439zwv.jpg

Hopefully the engine fit`s between the tracks like it`s shown here. If not, i need some new ideas...

http://up.picr.de/9327440opk.jpg

http://up.picr.de/9327441vtb.jpg

http://up.picr.de/9327442dbp.jpg

Found the first mistake. The joint should look like this:

http://up.picr.de/9327981bdj.jpg

Now i`m waiting for some measurements of the drivetrain, to see if the engine fits...

Cool little project.

nice idea. i'll be watching this build for sure!

subscribed

awesome. looking forward to seeing how this turns out.

Can`t wait to start this build, but i have to wait one or two weeks before i get my tax returns, then i can start buying parts and start the project...

At the moment i do some drawings for the joint between both cars. I`m not sure how to do it exactly, because i don`t have a lathe or a mill. But i thought i can use some Heims...

If you have some suggestions i`d be happy to hear them...

there have been a few articulated vehicle that come to mind. the US Gamma Goat was one though it it was wheeled and not tracked. the articulating drive should be similar.
another was the COOT vehicle. quite small, and again, wheeled. it was a swimmer also, and iirc, had a very simple articulation set up.
might try searching those two for some help.
good luck to you for sure!

How do you steer it? What's labeled in the drawing you found as "final drive gearbox" has to have something special going on inside it.

How do you steer it? What's labeled in the drawing you found as "final drive gearbox" has to have something special going on inside it.

It steers the same way the real thing does. The front and rear car are tilted against each other. You can compare it with a wheel loader. The final drive gearbox is just a normal axle, locked in the Hägglund. I think i`m going to weld the diffs too...

Started with the first track and sprocket design today. First mock up of the sprocket:

http://up.picr.de/9377214nws.jpg

Jig for the holes in the track:

http://up.picr.de/9377213xek.jpg

http://up.picr.de/9377215yvy.jpg

Tightening the bolts:

http://up.picr.de/9377216inq.jpg

First part finished:

http://up.picr.de/9377217mjr.jpg

Rear wheel:

http://up.picr.de/9377218mji.jpg

Sprocket, with updated design:

http://up.picr.de/9377219npn.jpg

Joint between both parts of the track:

http://up.picr.de/9377220vli.jpg

http://up.picr.de/9377221jbu.jpg

do you think that just the bolts keying with that sprocket will be enough to locate the track when it gets into a bind on a corner/terrain etc? maybe add some plates across the track between each bolt, with a piece that sticks up. also, why not use snowmobile parts? Sweet project for sure.

Awesome I will be following this closely

Would it be feasible to get rubber tracks from a small excavator or bobcat?

Whoa, this is getting a lot more interesting as I'm realizing just how 'creative' you are.

do you think that just the bolts keying with that sprocket will be enough to locate the track when it gets into a bind on a corner/terrain etc? maybe add some plates across the track between each bolt, with a piece that sticks up. also, why not use snowmobile parts? Sweet project for sure.

Hi, i know that this sprocket design won't work, it was just a try. I already have another solution, but i need to do some tests first...
Snowmobile parts are rare and very expensive in Germany, for example, a used track costs about $800...

Awesome I will be following this closely

Would it be feasible to get rubber tracks from a small excavator or bobcat?
I'll first try to make my own tracks. If this doesn't work i'll look for something like this...

Thanks for the comments, i like it to hear some thoughts...

Here the updated sprocket design. I think something like this could actually work...

http://up.picr.de/9409552mlx.jpg

Please note that this is just a try, not the finished design...

I also picked up the missing four tires for free:

http://up.picr.de/9409553ynf.jpg

i'm thinking some sort of blocks put over the exposed bolt threads to give the sprocket something more to bite against, and hold up better. the idea of using a brake disc is interesing

Would be awesome if it works with the brake disks. Because then i need nothing more for the driveline then the donor care has. I can just use the whole hub assembly...

I think that you will have reliability problems with welding steel tubing to a cast Iron disc...I would make steel "crown" rings that have the tubes welded to them and then bolt them to the discs.

Another thing to consider would be to split the tire belt lengthwise and bolt on spreaders to drive off of kind of how a snowcat does it
http://t3.gstatic.com/images?q=tbn:ANd9GcQtO3vfzD6yNRMBqyYl2V-zKOxNRPN3SX8tQAeayDh0o_hsk-yr1Q

Hi, yes i'll just use some steel disks that are the same size then the brake discs. But i think i'll try it first with the brake discs, maybe it holds up...

Where in DE are you? I just got back from living in bavaria for 4 years. Where abouts in Austria is the place? I got a ticket just over the Austrian border from Germany about 2 years ago. Fuckers :laughing:

Hi, were in Bavaria have you been? I assume in München when i look at your nickname...
I'm near Ulm, the place in Austria is called St. Gallenkirch...

I did go to Munich onc, but my wife was pregnant and not up to being to adventerous. Plus we booked the wrong hotel and had to stay in hallbergmoose .
I lived in Walldorf just outside of Heidelberg.
Have you ever been to K&s us car tuning ? Worked there briefly.

Damn, I saw a small excavator at a scrapyard not too long ago with all the hydraulics and interior removed. The bottom part seemed to be intact. Next time I see one I'll buy the fucker :laughing: since this project's got me quite interested.

I don`t think you could use this, because those tracks are not made for "high"speed and it would be heavy as hell...

But, if you could get it for cheap... :smokin:

So I had a random thought about your track/sprocket arrangement.

What about moving the bars to the tracks? Some chunks of wood or steel bolted across your already existing bolts. Then you could take two brake discs and flip them so the top hats were together, and simply notch them to grab the cleats on the tracks. Would do away with a lot of the stresses your welded brake rotor will see from those levers acting on it. Of course the downside is all of your bogey wheels would have to be cut out for the cleats.

it's still pretty sweet. I'm interested in how you're going to solve the articulating driveshaft problem.

Hi,
this would be a lot of work, and won`t work with the idler wheels...

For the sprocket i`ll cut a steel plate to weld the tubes to, like on the brake disk. Then i`ll gusset the hell out of it, so stresses won`t be a problem...

That`s the solution for the articulated driveshaft:

http://up.picr.de/9327981bdj.jpg

It steers the same way the real thing does. The front and rear car are tilted against each other. You can compare it with a wheel loader. The final drive gearbox is just a normal axle, locked in the Hägglund. I think i`m going to weld the diffs too...

Started with the first track and sprocket design today. First mock up of the sprocket:

http://up.picr.de/9377214nws.jpg

Jig for the holes in the track:

http://up.picr.de/9377213xek.jpg

http://up.picr.de/9377215yvy.jpg

Tightening the bolts:

http://up.picr.de/9377216inq.jpg

First part finished:

http://up.picr.de/9377217mjr.jpg

Rear wheel:

http://up.picr.de/9377218mji.jpg

Sprocket, with updated design:

http://up.picr.de/9377219npn.jpg

Joint between both parts of the track:

http://up.picr.de/9377220vli.jpg

http://up.picr.de/9377221jbu.jpg

your trak won't work. you'r gonna loose your bolt reel fast out of the ruber. lol here is a short story of my childhood that explained it. i bolted the tire of my bmx to do some in winther. put some 3/4" lenght bolt & some washer on both side of the tire. it performed flawlessly with a second tire to protect the tube.
my friend was amazed and he wanted to do it on it's montain bike. he grab 2" bolt lenght. make the bolted tire and he rolled on it. it funny cus it work for first 2-3 gears has speed grow he start receving bolts behind the head! lol it dident took long befor he stops. :D
the bolt was to long. leverage pop the washered bolt out of the tire.

you need to solidify the bolt with the trak. bigger washer or plate that grabs 2 bolts in tha trak wide.

good luck!

Hi,
those bolts are just about 1 3/4" long, and stick out about 1 1/4"...

A lot of dirt track racers bolt those bolts through their tires and race it without losing bolts. Those tire belts are really heavy duty, there`s no way to rip those bolts through them. I think they break instead of ripping out...

Subscribed.

I thought this might be useful.

Extreme Hagglunds - Track Building - YouTube (http://www.youtube.com/watch?v=zrWx8yxtsWo&feature=related)

plus the extended cab colorado converted to hagglund is sweet.

Extreme Hagglunds - Take a Tour - YouTube (http://www.youtube.com/watch?v=h-KHpy4bmB4&feature=mfu_in_order&list=UL)

Because of the fact that the Hägglund will be smaller than a car, i`m able to build it in my other shop. So i started to organizing both shops and getting all my metalworking stuff in my shop. Before:

http://up.picr.de/9446266znc.jpg

http://up.picr.de/9446267izi.jpg

When i called it a day:

http://up.picr.de/9446268roo.jpg

http://up.picr.de/9446269drp.jpg

http://up.picr.de/9446270yor.jpg

The old shop:

http://up.picr.de/9446272tmy.jpg

I also cut up all the tires and finished one track:

http://up.picr.de/9446271atl.jpg

interesting idea ... but IMHO i think you will run into a couple problems;

your bolted together "track" will not last long (without at least a little overlapping / vulcanizing) ... i would try to find a "one piece" belt loop (bigger tires ?!?)
you will most likely peel the track off the running gear in the first turn (your design has marginal side load support)
to much friction when your "driver wheel" engages the bolts; it will grind them down in no time.
questionable traction of the (worn tire) track.
...


when i grew up in switzerland i was often riding shotgun in "Pistenfahrzeuge" like this;
http://desmond.imageshack.us/Himg684/scaled.php?server=684&filename=img0490c.jpg&res=medium
as somebody else already suggested i would take a close look at that style of tracks ;
rubber loops with cross-ribs and driver "zahn-raeder" (sprockets ?) that engage into the ribs.

I thought this might be useful.

Extreme Hagglunds - Track Building - YouTube (http://www.youtube.com/watch?v=zrWx8yxtsWo&feature=related)

plus the extended cab colorado converted to hagglund is sweet.

Extreme Hagglunds - Take a Tour - YouTube (http://www.youtube.com/watch?v=h-KHpy4bmB4&feature=mfu_in_order&list=UL)

cool videos ! .... gives me stupid ideas :rolleyes: ... its not like i really need another project :p

Hi,
the connection between both tires will be updated, this is not the final design. But, here`s a connection on a Bombardier BR160 snowcat, this is a big rig and as you can see, it`s not a big connector:

http://www.forumsforums.com/3_9/attachment.php?attachmentid=52128&stc=1&d=1297046110

Look at this video. The track has almost no side support, and is only driven by friction. It obviously works. So, the forces can`t be that big. The one in the video does really sharp turns, mine won`t be able to do this because of the articulated steering. So there are a lot less sideway forces. I think my system is far superior in both things to the one in the video, so why shouldn`t it work?

Personal Tracked Vehicle - YouTube (http://www.youtube.com/watch?v=GRPHT9wm5cI)

I`m going to use this offroad too, so no Pistenbully tracks. But i`m going to add some u-brackets on the outside of the tracks for winter driving...

You will note in the vid that there are guides at the front and rear to keep the tracks on the tires. Also, it has very little power and probably weighs about as much as a riding lawn mower. You are taking about making a two part articulated vehicle that will not be a skid steer, but will turn based on hydraulic rams bending the vehicle to turn it. The act of bending in the middle may very well be enough force to push a track off the road wheels. If you are going to stay pretty lightweight, I'd probably look at using snow mobile parts since it's a proven setup and probably wouldn't cost that much to source and import if not available locally. Building something from scratch is always cool but there is not much point in redesigning the wheel, so to speak. Just my .02

Hi,
i know that there are guides on the front and rear, i bought the build plans from this guy. But it think the point where the track want`s to move sideways and needs to be guided is where the weight lasts on, it`s on the ground. This setup even works with the guides up in the air, where not much sideways force is applied. You don`t want to tell me that the bolts don`t hold the track better in place than those two guides? :eek:

There are also a lot of examples for tracked vehicles using tire tracks with almost no sideway guides, even with car engines in a bigger size, and all seem to work. It`s not like redesigning the wheel, it`s more looking what works and build it like that...

I don`t know if i posted it before, but used snowmobile tracks are around $800/piece in germany, so i won`t spend $3200 on tracks if i can try to make them myself...

Here`s a example of a Mattrack, using exactly the system for the sprocket and sideway guides that i wan`t to use:

http://images.canadianlisted.com/nlarge/mattracks-xt-ur-new_5522020.jpg

The bolted connection in the track is pretty common on older machines, a lot of machines running grousers will just overlap the belt a bit and bolt it together, but since your belting material is so heavy and thick a hinge type of connection will work better. Keep in mind that the BR hinge has a a lot of surface area and the backing plates are large and reach back into the track pretty far. What you have now will break very quickly.

That said I think your driver setup is going to last less than a 100 meters before it all flies apart. All machines have a rubber or poly on metal drive setup. Either they use poly sprockets and metal grousers or metal sprockets on rubber track nubs. Metal on metal is not going to work for very long.

For a very low buck system I think you should double up the track material and run metal grousers (cross bars) between the belts, something like every modern belt type track setup uses. That would give you a lot more track width for floatation and you could drive off the grousers. Then make some drive sprockets out of plastic (HDPE). You could easily cut them out of plastic with a router, double up the material for thickness, until you have a sprocket about 50mm thick.

I've been thinking about building something similar and I think this would be the ultimate setup for a low-cost track setup that will work well and provide some floatation. The track width you have is likely too narrow for good floatation.

edit: On the Pistenbully tracks, look into Nodwells, they use steel grousers for off-road, no problem.

The bolted connection in the track is pretty common on older machines, a lot of machines running grousers will just overlap the belt a bit and bolt it together, but since your belting material is so heavy and thick a hinge type of connection will work better. Keep in mind that the BR hinge has a a lot of surface area and the backing plates are large and reach back into the track pretty far. What you have now will break very quickly.



As said before, this is not the final version and needs an update. I`ll double it up with some long strips of conveyor belting...


That said I think your driver setup is going to last less than a 100 meters before it all flies apart. All machines have a rubber or poly on metal drive setup. Either they use poly sprockets and metal grousers or metal sprockets on rubber track nubs. Metal on metal is not going to work for very long.



I`m going to add some plastic over the steel tubes, so it`s not steel on steel. But i`m curious to hear what you think will fly apart?


For a very low buck system I think you should double up the track material and run metal grousers (cross bars) between the belts, something like every modern belt type track setup uses. That would give you a lot more track width for floatation and you could drive off the grousers. Then make some drive sprockets out of plastic (HDPE). You could easily cut them out of plastic with a router, double up the material for thickness, until you have a sprocket about 50mm thick.

I've been thinking about building something similar and I think this would be the ultimate setup for a low-cost track setup that will work well and provide some floatation. The track width you have is likely too narrow for good floatation.


I can`t make the tracks wider, because then it wouldn`t fit in my L300 and i couldn`t transport it...

I don`t need floatation for deep powder snow and something like this. Where i`ll run it is always a groomed trail, where the hunters use ATV`s with Mattracks and a Pistenbully, so the snow is always packed, you could always drive a car on it...

I think the bolts will bend or wear very quickly. The angle steel welded to the rim will also probably fail or vibrate like heck. If you are limited with track width maybe you can split the material you have lengthwise and put grousers across it. I really think that a plastic drive sprocket driving the grousers directly would be the easiest and most reliable system.

However, if you are not running powder, why tracks? Large tires with a lot of floatation (like a Rolligon) are no doubt cheaper and mechanically simpler. Then again a used snowmobile with a large sleigh would be cheaper. I doubt you can build anything cheaper than a used snowmobile needing some repairs.

Sorry man, but did you read the whole thread? The sprocket with the angle iron was bullshit, and i already posted the updated design, that`s almost the same as the Mattracks use:Here the updated sprocket design. I think something like this could actually work...

http://up.picr.de/9409552mlx.jpg

Please note that this is just a try, not the finished design...


Again, for winter driving i`m going to put grousers on the outside of the tracks to increase traction.

Why built it with tracks? Just because i want a tracked vehicle and i think the Hägglund concept is fucking awesome. I always wanted to build something like this...
And i think it has it`s advantages compared to a wheeled vehicle...

And to say it again: Snowmobile parts are expensive as hell. I think i can built this vehicle for about $500-$1000, a used snowmobile would cost me at least $2000... :eek:

Sorry, I thought you were going to use the rotor with the tubes welded to it as the rear idler.

Good luck with the project. I think it will be a learning experience for you.

No problem man, i'm going to use the big wheel in one of the first posts as rear idler wheel...

I think most of this project will be trial and error, because no one (that i know) has done it before. But, as we say in Germany: Theorie is when you know everything and nothing works. Practice (?) is when everything works and you don't know why...:flipoff2:

Theorie is when you know everything and nothing works. Practice (?) is when everything works and you don't know why...:flipoff2:

I'm totally stealing this the next time I have to deal with a software engineer.

Worked on the shop today. First i made a welding cart out of a old wood cart. The saw will be bolted on top:

http://up.picr.de/9472501scl.jpg

There will be tools hanging on the wall:

http://up.picr.de/9472503wjv.jpg

And something to get the welding fumes away:

http://up.picr.de/9472504jix.jpg

Do yourself a favor and mount a fire extinguisher onto your cart. Not sure why every welding cart doesn't have one.

Do a search for the DTV shredder. I'd sure like to buy one, but they're not in full production yet. Maybe you can get some ideas from their website.

There`s always a fire extinguisher mounted in my shop. Would be stupid if a firefighter burns his own house because he didn`t have a fire extinguisher ready while welding... :rolleyes:

Put some more work in the shop today:

http://up.picr.de/9481861gai.jpg

http://up.picr.de/9481865vxt.jpg

this guy:
http://www.youtube.com/user/Gizmo4t?feature=watch

builds 1/2 scale tanks that run and drive. He's got a bunch of tech related videos on there that might be useful.

Cool build!:D

I'm not sure if you've seen it yet, but there's a good thread in Gen4x4 with a lot of info and ideas on track design:

http://www.pirate4x4.com/forum/showthread.php?t=854333

I`ve read that thread many times, there`s a lot of interesting tech going on there...

Finished the shop today:

http://up.picr.de/9515984fab.jpg

http://up.picr.de/9515977huh.jpg

http://up.picr.de/9515978unt.jpg

http://up.picr.de/9515980aio.jpg

http://up.picr.de/9515982fqa.jpg

The red markers show the dimensions of the Hägglund:

http://up.picr.de/9515983ndw.jpg

When i`m back from skiing i`ll pick up the donor car and start the project...

I think you are on the right track and with some of the advice on here, you will be served well.

Have you considered trying to source U.S. parts and ship them over? You are re-inventing the wheel so to speak, which is always a sure way to increase the amount of heartache and work you will endure.

I understand your size limitations, but I believe you would be better served with lightweight snowmobile tracks, which can be bought in smaller sizes for a lot less than it's going to cost you to make your tracks, and they will hold up much better for what you are looking to do.

They make youth models of snowmobiles, which have much smaller tracks on them. They are also a lot cheaper. Shipping would be the most expensive part of the deal. Perhaps you could source some from an adjacent area?

Have you considered trying to source U.S. parts and ship them over?


Hi,
i don`t know if you ever shipped parts from the U.S. to europe, but i did a lot. I can tell you that it`s expensive as hell, especially for big parts like snowmobile tracks. And if i would go with snowmobile tracks i`d also have to use snowmobile idler wheels and sprockets...

You are re-inventing the wheel so to speak, which is always a sure way to increase the amount of heartache and work you will endure.


As already stated, there are a lot of homemade tracked vehicles using tires as tracks. So it`s not reinventing the wheel, i`m taking ideas from guys that built some successfully and trying to improve them...


I understand your size limitations, but I believe you would be better served with lightweight snowmobile tracks, which can be bought in smaller sizes for a lot less than it's going to cost you to make your tracks, and they will hold up much better for what you are looking to do.


Well, i`m not sure why you think it`d cost a lot to make my tracks, because it doesn`t cost me anything. I got the tires for free, and have the bolts already laying around...
I`m just trying to built it like i think it`ll work. If it doesn`t work, well then it`s a lot of wasted time, but not more. Then i`ll start looking for alternatives, but will most likely built some real snowcat tracks, out of conveyor belts and grousers. But since i have a lot of free time at the moment i`ll just try my ideas first... :flipoff2: ;)

Don`t take this as offense, my english isn`t that good, so it could sound like that. I`m always happy to hear some other opinions and thoughts, but please don`t talk about snowmobile parts anymore, because this just won`t happen... Thanks... :beer:

I think i came up with a pretty good solution for connecting the tracks:

http://up.picr.de/9522624qlx.jpg

The orange fabric has a breaking strength of about 2.5 tons, so i think it should hold up fine... :smokin:

I think i came up with a pretty good solution for connecting the tracks:

http://up.picr.de/9522624qlx.jpg

The orange fabric has a breaking strength of about 2.5 tons, so i think it should hold up fine... :smokin:

Seems like a good idea,
Maybe use this to line the bolts around the whole track to keep the washers from pulling out over time, might help make the track more solid to hold the bolts.

Just a hunch

Webbing is very strong but it wears poorly and will weaken as it frays.

Seems like a good idea,
Maybe use this to line the bolts around the whole track to keep the washers from pulling out over time, might help make the track more solid to hold the bolts.

Just a hunch

Sounds like a plan if the tracks aren`t holding up...

Webbing is very strong but it wears poorly and will weaken as it frays.

I burnt the holes in instead of drilling them, so it shouldn`t fray out much. Time will tell...



What i could use some help is the steering. I was planning on using the steering rack from the donor car, but because the steering wheel is on front and the steering rack on the rear, the steering column is going to be complicated. I already came up with an solution for the steering rack, but it´d be complicated with a lot of u-joints and stuff...
So the best would be finding an orbitrol and doing full hydro, but that`s the same as for snowmobile tracks, there are just ridiculous expensive. Anyone has an idea for that?

This is what i was thinking, but please keep in mind that i have no ideas how that kind of stuff really works:
I know how you guys do hydro-assist with tapping the steering box and adding a hydraulic ram. Would it be possible to do a setup like this without connecting the steering box to the actual steering? Like mounting the tapped steering box like an oribtrol and using the hydraulic ram for steering? But from what i understood this won`t work, because the steering box needs to be connected to the actual steering to work as a valve...

Would be nice to hear some advice on this, because i know you guys know more than me about this kind of stuff.. :

is having a steering wheel a requirement?

A simple spool valve could run your two cylinders:

http://www.northerntool.com/shop/tools/product_200339049_200339049?cm_mmc=Aggregates-_-Google-_-Hydraulics%3EHydraulic%20Valves-_-201612

and should be somehting you can find off just about any piece of heavy equipment.

I was referring to the wear from the contact with the metal drive sprockets. It will work, but may require frequent repair.

is having a steering wheel a requirement?

A simple spool valve could run your two cylinders:

http://www.northerntool.com/shop/tools/product_200339049_200339049?cm_mmc=Aggregates-_-Google-_-Hydraulics%3EHydraulic%20Valves-_-201612

and should be somehting you can find off just about any piece of heavy equipment.

I thought about that too, but wouldn't it be hard to return to the neutral position?
Oh, and i just need one cylinder (at least i think so ;-D)

I was referring to the wear from the contact with the metal drive sprockets. It will work, but may require frequent repair.

I thought i put some rubber on the sprocket, so that shouldn't be a problem...

I thought about that too, but wouldn't it be hard to return to the neutral position?
Oh, and i just need one cylinder (at least i think so ;-D)



I thought i put some rubber on the sprocket, so that shouldn't be a problem...

a little, but I kind of figured this thing isn't going to be running down the road at 60 MPH either, lots of rollers and road grading stuff uses a hydraulic tiller and does just fine at 10 MPH.
It just takes a little bit to get used to driving one. slight "bumps" of the control lever to get your straightened out.

not to sound negative (heck you can blow your free time on whatever you want :flipoff2: :p )
... but what i dont understand is why you want to go with this (imho overly complex) design :confused:

if i understand you right you want the Rig to fit into the back of your minivan
(that has most likely not a very large cargo capacity) and are not going to use the rig in wide open tundra ...
...so for me the length of 4 tracks and the large turning radius of a "articulating frame" steering just does not really make sense.

what is your reason to not just stick to a (imho shorter, lighter and simpler) 2 track design and the almost "zero radius" steering of open diff/2 lever cutting brakes ?

a little, but I kind of figured this thing isn't going to be running down the road at 60 MPH either, lots of rollers and road grading stuff uses a hydraulic tiller and does just fine at 10 MPH.
It just takes a little bit to get used to driving one. slight "bumps" of the control lever to get your straightened out.

You're right, i think that's probably the way to go. But i just had an idea to do a self centering setup. But this is way down the road...

not to sound negative (heck you can blow your free time on whatever you want :flipoff2: :p )
... but what i dont understand is why you want to go with this (imho overly complex) design :confused:

if i understand you right you want the Rig to fit into the back of your minivan
(that has most likely not a very large cargo capacity) and are not going to use the rig in wide open tundra ...
...so for me the length of 4 tracks and the large turning radius of a "articulating frame" steering just does not really make sense.

what is your reason to not just stick to a (imho shorter, lighter and simpler) 2 track design and the almost "zero radius" steering of open diff/2 lever cutting brakes ?

Ok, I'll try to explain: First of all, the van has a one ton load capacity, so i think i'd do something wrong if it weights more than that...

Why going with an articulated design? A two tracked vehicle this long and narrow wouldn't make much sense because it'd flip easy. I also don't want to make it any smaller, because i want it to be able to carry some stuff.
I think the bigger turning radius is even an advantage over the zero turning radius because the side load on the tracks is a lot less... Also the articulated design is a lot more capable if its the same size vehicle...

And the most important reason: I just think its freaking cool, and i liked that design for years...

Can't help but be reminded of this:

http://media.techeblog.com/images/lawnmowertank_2.jpg

http://www.techeblog.com/index.php/tech-gadget/lawn-mower-tank-doubles-as-snow-plow-priced-at-11-999

If it's going to fit in the back of a minivan, at least what we call a minivan over here, it's not going to be much bigger than a lawnmower.

No offense taken. Not trying to talk you out of something, but as a person who has wasted a lot of his life trying to make something work cheap, then having to go back a few years later and do it right the second time, I have a bit of experience in doing things poorly.

Something I have learned the hard way from my own and others experiences, is that there is no amount of money in the world that is worth watching someone you love get hurt or be in danger of freezing because you wanted to save some money. I also have a strong aversion to walking because my rig broke, so you could call me lazy. I've also had to fix things in the snow and mud, which quite frankly, sucks.

You are right that the tire tracks have been done before. What is different is your method of driving them. Internal grousers are a proven design for a reason. They work. Your method lacks the strength that you will need to prevent destruction of the track if the drive wheel should slip, the track lose tension or slip from the rollers or drive sprocket. As you have stated, the pictures above are ideas in the making and plans that are being discarded as they do not work out. This is good.

I think you can use the bolts you already have installed, but make connectors between them, with raised cogs to drive on your sprocket. This would spread the load between four bolts, rather than just two, and not add too much complexity or weight if done right. If these connectors were designed that the four bolts were tied together, across the track, then you would gain the stiffness you need in the track for turning, as well as load distribution between 4 bolts rather than only 2 at a time.

If you plan on using rubber tires for your carriage wheels, then you can design them to run inside the connectors, which would be basically an internal grouser, and they would keep the track aligned.

Steering: Is this to be articulated in the center with the steering as that of an articulating tractor? If so, then hydraulic cylinders are the only way to get the strength you need.

As with everything else, you need to do as the professional engineers do, over build it, because you never know what will happen or where you may wind up, and you don't want to build it with the idea that you will always be on a packed trail, with perfect conditions. With cylinders, you will be well served with a joystick control on a valve, unless you want to build an orbital steering setup. Orbitals bring on all kinds of plumbing and mounting issues, whereas a simple hydraulic valve can be very easy to configure.

Have you considered using turning brakes on the front portion, and just allowing the rear to follow, as a trailer would do? If you did turning brakes on both the tow vehicle and the trailing portion, you could easily make them work on opposite tracks, thereby forcing your two portions to pivot faster and work with each other, rather than having only one end of the vehicle do all the turning. With turning brakes you cannot weld the differentials solid, but you may gain maneuverability and control that you may not have with just the rams to steer with.

We have not discussed your options with regard to salvage yards, or equipment. If you have access to a rural area with agriculture, then you may be able to source a lot of things that will help you build this easier. Otherwise, you are going to have to figure out how to make automotive stuff work. Weight is going to be an issue for you with your desired method of transportation. Have you determined a gross unladen weight target? Have you weighed the engine and drive components you are going to use?

I looked at your rotor with the drive cogs on it. It's a good example, but the rotor itself will not work as you have done the cogs. Rotors are traditionally cast iron, and unless you are better than average at welding cast iron to steel, the joints will be brittle and subject to fracture under shock loading. The only way I can see that working, is if you drilled a hole through the rotor, tight enough that the pipe would barely fit through, then add gussets from the pipe to the rotor center. This would require heating the rotor, piping and gussets to at least 500 degrees in an oven, then welding and reheating to keep the temp of the whole thing above 500 degrees. Then either bury it in hot sand, or wrap it in blankets so it cools slowly. The key is to allow them to cool at a speed that prevents the two metals, which will contract at differing rates, to cool slow enough they don't stress the joint and crack.

I'm thinking that adding angle iron (or aluminum if you prefer) to the bolts as mentioned above and for a drive wheel, a normal wheel of the correct width with round stock or bars of some sort welded across the width of the wheel. You could even go a step farther and use a rim wide enough that the entire track would fit in between the rims sides to help keep it in line and then put the drive bars deeper in the rim. Not sure if I explained that so that it makes sense, but I'm thinking of drive sprockets along the lines of what is used on the Ripsaw:

http://www.spoki.lv/upload/articles/30/302796/images/_origin_ripsaw-ms-1-2.jpg

The drive "teeth" down the center of the track may complicate how your road wheels will be arranged, but it seems, to me at at least, to be the easiest and most secure way to drive the tracks. I fear the bolts alone will be a dismal failure due to their lack of individual strength and the flexing of the rubber.

interesting idea ... but IMHO i think you will run into a couple problems;

your bolted together "track" will not last long (without at least a little overlapping / vulcanizing) ... i would try to find a "one piece" belt loop (bigger tires ?!?)
you will most likely peel the track off the running gear in the first turn (your design has marginal side load support)
to much friction when your "driver wheel" engages the bolts; it will grind them down in no time.
questionable traction of the (worn tire) track.
...


when i grew up in switzerland i was often riding shotgun in "Pistenfahrzeuge" like this;
http://desmond.imageshack.us/Himg684/scaled.php?server=684&filename=img0490c.jpg&res=medium
as somebody else already suggested i would take a close look at that style of tracks ;
rubber loops with cross-ribs and driver "zahn-raeder" (sprockets ?) that engage into the ribs.
thx that whas the name of what i tried to describ: "cross-ribs" that's what you need to hold your bolts to the ruber.

Can't help but be reminded of this:


http://www.techeblog.com/index.php/tech-gadget/lawn-mower-tank-doubles-as-snow-plow-priced-at-11-999

If it's going to fit in the back of a minivan, at least what we call a minivan over here, it's not going to be much bigger than a lawnmower.

I`ve never called my L300 a minivan, and i wouldn`t call it that, because it has almost a one ton carrying capacity. The final dimensions will be 47" wide and 138" long...



You are right that the tire tracks have been done before. What is different is your method of driving them. Internal grousers are a proven design for a reason. They work. Your method lacks the strength that you will need to prevent destruction of the track if the drive wheel should slip, the track lose tension or slip from the rollers or drive sprocket. As you have stated, the pictures above are ideas in the making and plans that are being discarded as they do not work out. This is good.



Yes, i like trying things and look at them in real life instead of just a CAD model. This way i get a lot of good ideas...


I think you can use the bolts you already have installed, but make connectors between them, with raised cogs to drive on your sprocket. This would spread the load between four bolts, rather than just two, and not add too much complexity or weight if done right. If these connectors were designed that the four bolts were tied together, across the track, then you would gain the stiffness you need in the track for turning, as well as load distribution between 4 bolts rather than only 2 at a time.

If you plan on using rubber tires for your carriage wheels, then you can design them to run inside the connectors, which would be basically an internal grouser, and they would keep the track aligned.



I`m still thinking that the bolts are strong enough. But if not i`ll do exactly what you said. Shouldn`t be a problem to add them later...


Steering: Is this to be articulated in the center with the steering as that of an articulating tractor? If so, then hydraulic cylinders are the only way to get the strength you need.

As with everything else, you need to do as the professional engineers do, over build it, because you never know what will happen or where you may wind up, and you don't want to build it with the idea that you will always be on a packed trail, with perfect conditions. With cylinders, you will be well served with a joystick control on a valve, unless you want to build an orbital steering setup. Orbitals bring on all kinds of plumbing and mounting issues, whereas a simple hydraulic valve can be very easy to configure.



You`re right, it will be articulated steering using an hydraulic ram. I think i`ll use a normal 4/3-way valve, but outfit it with an self centering setup and a joystick...


Have you considered using turning brakes on the front portion, and just allowing the rear to follow, as a trailer would do? If you did turning brakes on both the tow vehicle and the trailing portion, you could easily make them work on opposite tracks, thereby forcing your two portions to pivot faster and work with each other, rather than having only one end of the vehicle do all the turning. With turning brakes you cannot weld the differentials solid, but you may gain maneuverability and control that you may not have with just the rams to steer with.


I thought about that but decided against it. First of all it`s a lot more complicated, because i`d have to add brakes on all 4 sprockets. I also think it`d be dangerous if i can`t control the angle between both cars. Just think driving on a slope and the second car starts sliding downhill. The big Hägglund also uses articulated steering and locked differentials. I think with open differentials it wouldn`t drive well, because the tracks need a lot more power to turn, so i think spinning one track would happen a lot...


We have not discussed your options with regard to salvage yards, or equipment. If you have access to a rural area with agriculture, then you may be able to source a lot of things that will help you build this easier. Otherwise, you are going to have to figure out how to make automotive stuff work. Weight is going to be an issue for you with your desired method of transportation. Have you determined a gross unladen weight target? Have you weighed the engine and drive components you are going to use?


Well, those options are easy to discuss, because we don`t have salvage yards here like you guys do...
But i don`t see any problems with using the automotive parts, it should work well. No idea on weight yet, but it think about 400-500kg. The donor car weights about 800kg, no numbers on individual parts yet...
As said before, my L300 can handle almost one ton payload, so it should be find...


I looked at your rotor with the drive cogs on it. It's a good example, but the rotor itself will not work as you have done the cogs. Rotors are traditionally cast iron, and unless you are better than average at welding cast iron to steel, the joints will be brittle and subject to fracture under shock loading. The only way I can see that working, is if you drilled a hole through the rotor, tight enough that the pipe would barely fit through, then add gussets from the pipe to the rotor center. This would require heating the rotor, piping and gussets to at least 500 degrees in an oven, then welding and reheating to keep the temp of the whole thing above 500 degrees. Then either bury it in hot sand, or wrap it in blankets so it cools slowly. The key is to allow them to cool at a speed that prevents the two metals, which will contract at differing rates, to cool slow enough they don't stress the joint and crack.

That was just a test, see below...

I'm thinking that adding angle iron (or aluminum if you prefer) to the bolts as mentioned above and for a drive wheel, a normal wheel of the correct width with round stock or bars of some sort welded across the width of the wheel. You could even go a step farther and use a rim wide enough that the entire track would fit in between the rims sides to help keep it in line and then put the drive bars deeper in the rim. Not sure if I explained that so that it makes sense, but I'm thinking of drive sprockets along the lines of what is used on the Ripsaw:

The drive "teeth" down the center of the track may complicate how your road wheels will be arranged, but it seems, to me at at least, to be the easiest and most secure way to drive the tracks. I fear the bolts alone will be a dismal failure due to their lack of individual strength and the flexing of the rubber.

Like i mentioned above, if the bolts fail i`ll do that. For the sprockets see below...


Ok, so i started with the first real prototype of the drive sprocket today. This is the drawing:

http://up.picr.de/9550565ara.jpg

Then i started fabricating it:

http://up.picr.de/9550566otr.jpg

http://up.picr.de/9550567qab.jpg

http://up.picr.de/9550568sep.jpg

Unfortunately i`m missing a 20mm drill bit, so i couldn`t finish it. But i just had to tack some tubes on to test if it works. Well, it fit like it was designed for it... :eek: ;)

http://up.picr.de/9550569hkx.jpg

I`ll add some flat stock between the tubes to center the track, same principle as elwenil mentioned...

http://up.picr.de/9550570szl.jpg

I think this is the way to go, i`m really happy that it works like i thought... :)

Looking very good.

If you were to use square stock, rather than round, it would tend to keep the bolt supported better. With a round driver, the bolt will have very little surface area supporting it, and will be more inclined to tilt. The square stock would also strike the bolt closer to the rubber, lessening the leverage on the bolt and the rubber, it might even drive off the nut, making the leverage almost non existent.

As for salvage yards, I encountered a similar thing in New Zealand. I was there 2 weeks and only in the most rural areas, did I find non working autos, or equipment sitting around waiting to be used for parts. The rest of the country appeared to recycle everything that wasn't alive and growing out of the ground.

Very strange for a country boy from farm land to experience.

Thanks.
Here's a drawing that shows why i think the tubes are better:

http://up.picr.de/9449523xky.png

Also if i would use square stock, everything has to be perfectly aligned, and i know that i'm not able to do it perfectly...

And for salvage yards, i thought i was in paradise when i went to canada and saw all those scrapyards and the heavy equipment yards...

you gone bend the bolts under load i think

So are you building a low track with no road wheels or bogies or are you building a Christie type track or what? It looks by your diagram above that you are going to do something similar to the lawn mower pic I posted above or are the drive wheels going to be elevated with bogies supporting the weight and the drive wheels only used to propel the track with return rollers or Christie road wheels to support the track? If you are only using a drive wheel and an idler, I think this thing will be very rough riding and will not have the low ground pressure tank treads are famous for.

Having worked on some tracked vehicles before, I think that you might be better served by putting your track locator to the inside of the bolts.

I was thinking a V shape on the plate of your drive sprocket to help locate and guide the bolts and keep the disc centered.

If the nylon webbing fails, why not just use another scrap of tire to make the "hinge" of even double up tires and stagger the joints? I also like the idea of plates running perpendicular to your tracks where the bolts go through, it would be an easy way to add some more traction.

So are you building a low track with no road wheels or bogies or are you building a Christie type track or what? It looks by your diagram above that you are going to do something similar to the lawn mower pic I posted above or are the drive wheels going to be elevated with bogies supporting the weight and the drive wheels only used to propel the track with return rollers or Christie road wheels to support the track? If you are only using a drive wheel and an idler, I think this thing will be very rough riding and will not have the low ground pressure tank treads are famous for.

I stick to my drawings, a bigger idler wheel, two bogies and the elevated sprocket:

http://up.picr.de/9327435yvf.jpg

Having worked on some tracked vehicles before, I think that you might be better served by putting your track locator to the inside of the bolts.

I was thinking a V shape on the plate of your drive sprocket to help locate and guide the bolts and keep the disc centered.


Thats a good idea, i`ll do that. What do you think would be the best design of the plate?


If the nylon webbing fails, why not just use another scrap of tire to make the "hinge" of even double up tires and stagger the joints? I also like the idea of plates running perpendicular to your tracks where the bolts go through, it would be an easy way to add some more traction.

I can`t use anything bigger then the webbing, because it would change the thickness of the track. But i`m going to add some angle iron to the outside of the tracks in the winter to add some traction...


Oh, and my buddy gave me two of those today:

http://up.picr.de/9559320ems.jpg

Let`s see if i can use them...

Got the hydraulic cylinders today:

http://up.picr.de/9568166jho.jpg

http://up.picr.de/9568168dja.jpg

http://up.picr.de/9568171qsv.jpg

http://up.picr.de/9568173sxv.jpg

http://up.picr.de/9568174xwz.jpg

This one has a damaged piston, but i`ll use it to control the vertical motion of both cars. This requires almost no pressure, so it`ll be fine...

http://up.picr.de/9568177krl.jpg

Once that orange banding starts to fray it will pick up every little piece of debris you roll over.

I use it for banding together lumber. It is good stuff.

Worked on the sprocket today:

http://up.picr.de/9605683ypx.jpg

http://up.picr.de/9605684qbz.jpg

http://up.picr.de/9605686vcz.jpg

http://up.picr.de/9605687yxl.jpg

That`s my idea for centering it, but i`m not really happy with it. Any better ideas?

http://up.picr.de/9605688kwt.jpg

http://up.picr.de/9605689arp.jpg

here is what i would do;

i would not do the filler pieces of flat stock and i dont think the rubber sleeves will last long if they rub against the bolts :shaking: ...

i would cut rings that weld onto the outside of the cross-tubings

replace the nuts with custom turned "spikes" (maybe ~1" stock ...with a nice smooth bullet nose) that are treated to screw over the bolts.
maybe run even larger (hardened) washers to avoid that the spikes fold over.
the pointy spikes should fairly well "self-center" into the driver spocket (just dont make them too tall or you may run into misalignement problems as you pointed out in the side drawing)
... the metal to metal contact may even work-hardens itself some ...

You could try building internal drive teeth that will be held on with the bolt.

I don't have a drawing program, but I'm thinking small square tubing in short lengths that will fit between your drive teeth. Then put a short piece of angle on top to give the tooth a pointed top. If you angle cut the tubing, you can make it ramp from the point down to the track. Then all you would need is to put your guide plates on the ends of the tubes. This would do 2 things. It would strengthen your drive tubes, and provide a positive stop so your drive teeth could not go out the end of the sprocket.

The small lengths of tubing, I would drill them all the way through and try to get your bolt to go through both sides to strengthen the bolt and spread the drive forces into a shear load rather than a bending load on your bolt.

Probably a little late, but check this out:

http://www.southernairboat.com/classifieds/data/503/large/0062.JPG

Here in Florida, they used to build fully tracked swamp buggies. Most used conveyor belt material / bolts / angle or channel iron and car tires for the bogies. I hunted for some pics but non so far showed the tracks very well. I did find this and it seems like a good idea especially in a lower torque scenario.

Looks like it was a solid rubber forklift tire / wheel that was drilled and cut to make it a drive sprocket. Seems interesting.

here is what i would do;

i would not do the filler pieces of flat stock and i dont think the rubber sleeves will last long if they rub against the bolts :shaking: ...

i would cut rings that weld onto the outside of the cross-tubings

replace the nuts with custom turned "spikes" (maybe ~1" stock ...with a nice smooth bullet nose) that are treated to screw over the bolts.
maybe run even larger (hardened) washers to avoid that the spikes fold over.
the pointy spikes should fairly well "self-center" into the driver spocket (just dont make them too tall or you may run into misalignement problems as you pointed out in the side drawing)
... the metal to metal contact may even work-hardens itself some ...

leave the nuts you have now, stack some acorn style nuts on top.
enjoy ghetto fabulous spikes.

i would cut rings that weld onto the outside of the cross-tubings

replace the nuts with custom turned "spikes" (maybe ~1" stock ...with a nice smooth bullet nose) that are treated to screw over the bolts.
maybe run even larger (hardened) washers to avoid that the spikes fold over.
the pointy spikes should fairly well "self-center" into the driver spocket (just dont make them too tall or you may run into misalignement problems as you pointed out in the side drawing)
... the metal to metal contact may even work-hardens itself some ...

Hmm, sounds like a good idea, but there`s no way i`m going to machine 500pc of those spikes... :eek:

You could try building internal drive teeth that will be held on with the bolt.

I don't have a drawing program, but I'm thinking small square tubing in short lengths that will fit between your drive teeth. Then put a short piece of angle on top to give the tooth a pointed top. If you angle cut the tubing, you can make it ramp from the point down to the track. Then all you would need is to put your guide plates on the ends of the tubes. This would do 2 things. It would strengthen your drive tubes, and provide a positive stop so your drive teeth could not go out the end of the sprocket.

The small lengths of tubing, I would drill them all the way through and try to get your bolt to go through both sides to strengthen the bolt and spread the drive forces into a shear load rather than a bending load on your bolt.

Probably a little late, but check this out:

http://www.southernairboat.com/classifieds/data/503/large/0062.JPG

Here in Florida, they used to build fully tracked swamp buggies. Most used conveyor belt material / bolts / angle or channel iron and car tires for the bogies. I hunted for some pics but non so far showed the tracks very well. I did find this and it seems like a good idea especially in a lower torque scenario.

Looks like it was a solid rubber forklift tire / wheel that was drilled and cut to make it a drive sprocket. Seems interesting.

That`s exactly what i`m going to do if my tracks won`t work. But chances are low, see below...

leave the nuts you have now, stack some acorn style nuts on top.
enjoy ghetto fabulous spikes.

Sounds easy, but i don`t get the idea why it`s better with those nuts on? :confused:

Made a prototype of the track assembly today. Everything works perfectly, exactly like i thought:

http://up.picr.de/9662553guu.jpg

http://up.picr.de/9662556xdx.jpg

The second track connection is just improvised, but it already works perfectly. I even got a video if you guys want to see it...

Of course i had to take a seat:

http://up.picr.de/9662557oqz.jpg

http://up.picr.de/9662558tvn.jpg

I still have to design a (easy to make) centering device for the drive sprocket, any ideas?

Sure aint gonna be fast is it... You have more ambishin (<--positive thats spelled wrong) in your little German neck than I do in my whole body. Good luck man.

Very creative and interesting project Keep it going!

Thanks guys. I`m going to pick up the donor car next weekend:

http://up.picr.de/9692577ehh.jpg

1,2l 3cyl 75hp...

I think I'd be more tempted to torch the lower half of the sides off, mount drive sprockets to the hubs, build a suspension setup for some road wheels and run that as is.

That or copy what the Russian's are doing:

METELICA.flv - YouTube (http://www.youtube.com/watch?v=MtacFlDUjRM&feature=player_embedded)

:D

Never searched for any of this stuff before but YouTube seems to be full of little projects like this.


Mini Tank Test Drive - YouTube (http://www.youtube.com/watch?v=XpsYR0Ydq6w&feature=related)

Extreme Hagglunds - Track Building - YouTube (http://www.youtube.com/watch?v=zrWx8yxtsWo&feature=related)

tracked pocket bike - YouTube (http://www.youtube.com/watch?v=twt57zxMzGA&feature=related)

tracked offroad vehicle - YouTube (http://www.youtube.com/watch?v=NWiXIoINcb0&feature=related)

Bandvagn 2.3 D - YouTube (http://www.youtube.com/watch?v=A1r1Ac-3K58&feature=related)

Yeah i know. Most of them use some kind of sprockets (if not friction driven) and guides that are similar to my idea...

I think more importantly, most of the larger and heavier vehicles seem to use some sort of crossbar on the track for the sprockets to grip. I fear that as soon as you get your vehicle on a hard pull, it's just going to start slipping the sprocket and bending the bolts.

That`s something that needs to be tried. I think no one can say it works or not...
But i think i`ll add some bars to the outside to increase traction, they should help stabilize the bolts too.
And if it doesn`t work, i`ll just build some snowcat tracks...

Worked on the shop a bit today:

Before:

http://up.picr.de/9717696jff.jpg

During:

http://up.picr.de/9717692jus.jpg

http://up.picr.de/9717752wuc.jpg

http://up.picr.de/9717775msv.jpg

http://up.picr.de/9717767lnr.jpg

http://up.picr.de/9717781ypp.jpg

http://up.picr.de/9717779ipe.jpg

http://up.picr.de/9717778gfq.jpg

Finished:

http://up.picr.de/9717801yoz.jpg

http://up.picr.de/9717802trr.jpg

It`s nice to have some daylight in the shop...

Got the donor car today:

http://up.picr.de/9784192rin.jpg

http://up.picr.de/9784184jiv.jpg

The battery was completely dead, so we put in another one. It turned over on the first try and ran fine...

http://up.picr.de/9784207ofp.jpg

We drove a few feet and started parting it out:

http://up.picr.de/9784191rnt.jpg

http://up.picr.de/9784198shx.jpg

http://up.picr.de/9784228mjq.jpg

After two hours of work:

http://up.picr.de/9784236oco.jpg

http://up.picr.de/9784237hrn.jpg

http://up.picr.de/9784238sdd.jpg

Built some track-assembly dummies to get an idea of the size. We can place all the parts where they`re supposed to go, so we can see easily if there`s enough room or not:

http://up.picr.de/9792256mer.jpg

The little one had to check things out:

http://up.picr.de/9792267etu.jpg

This is about where i`ll sit:

http://up.picr.de/9792271gwg.jpg

http://up.picr.de/9792273ray.jpg

Placed some stuff today, this is going to be tight:

http://up.picr.de/9818175cqi.jpg

http://up.picr.de/9818177urx.jpg

This is about half of the wiring loom. That`s insane... :wow1:

http://up.picr.de/9818174jew.jpg

You look like Sheldon from the television show "Big Bang Theory".

this is awesome!!!

this could be awesome! keep up the work

Removed the engine today. Was a pain in the ass...

http://up.picr.de/9844694vol.jpg

http://up.picr.de/9844695nuu.jpg

Looks like it`ll fit, i`m really happy about that...

http://up.picr.de/9844711kfo.jpg

http://up.picr.de/9844712dwk.jpg

http://up.picr.de/9844713adb.jpg

are you going to use the justy transmission? those things are know to be incredibly weak even with the stock power levels, manual or automatic. Some good info http://www.dustysjustys.com/home.htm

other than that its looking good and cant wait to see more progress.

Here are a few more pictures from removing the engine:

http://up.picr.de/9862169gmk.jpg

http://up.picr.de/9862170ozr.jpg

http://up.picr.de/9862172idn.jpg

Also was able to have a look at a real Hägglund yesterday:

http://up.picr.de/9862171veo.jpg

are you going to use the justy transmission? those things are know to be incredibly weak even with the stock power levels, manual or automatic. Some good info http://www.dustysjustys.com/home.htm

other than that its looking good and cant wait to see more progress.

Yes i do. I don`t think there will be any problems. The Hägglund will weight less than the Justy, and the drive wheels are about half the diameter. So it`s like i`m driving in Lo...

Got a lot of steel tubes almost for free:

http://up.picr.de/9868301buq.jpg

http://up.picr.de/9868306jce.jpg

About 20 shorter pieces are still in my van....

Also bought a saw, to handle all that stuff:

http://up.picr.de/9868481mvp.jpg

sounds good then, good luck with your project.

So, we parked the Justy for some good access to the axles:

http://up.picr.de/9881477wsu.jpg

http://up.picr.de/9881484gdi.jpg

http://up.picr.de/9881487ddv.jpg

http://up.picr.de/9881488pur.jpg

Awesome, I had no idea that redneck had made to Germany. Love it.

Awesome, I had no idea that redneck had made to Germany. Love it.

his neighbors must love him already. just moved in and trashing up the place.
:laughing:

his neighbors must love him already. just moved in and trashing up the place.
:laughing:

Well, it`s just the third car i`m parting out there. And i was already there when most of my neighbors moved in...
:flipoff2:

Picked up the saw today:

http://up.picr.de/9890145wjh.jpg

After a bit cleaning, fresh oil and dialing in it runs like on it`s first day:

http://up.picr.de/9890143ybx.jpg

Bought it for about $200, the seller thought it`d be broken...

Finished parting out the Justy yesterday. Here`s a pic of removing the rear axle:

http://up.picr.de/9908369pid.jpg

Made a roller stand (?) for my saw:

http://up.picr.de/9908390nrz.jpg

http://up.picr.de/9908391suw.jpg

Also a jack stand for some welding practice:

http://up.picr.de/9908392luf.jpg

Will pick up the steel tomorrow, so i`m going to have the first track assembly ready by Saturday...

Couldn`t get the steel today, maybe tomorrow if i`m lucky...

We started making a hole in the wall for ("thing that evacuates welding fumes" how`s this called?):

http://up.picr.de/9916941lwh.jpg

http://up.picr.de/9916931xxs.jpg

Also made a stack for shorter pieces of steel:

http://up.picr.de/9916933mnr.jpg


What i need now is an idea what to use for the turning connection between both cars. There`s the up and down and the left and right movement between both cars. I already designed the joint for that. Now i need a joint that is able to turn around itself and fitting a driveshaft through it. Something like the "thing" that`s between the upper and lower part of an excavator and allows it to turn...

Couldn`t get the steel today, maybe tomorrow if i`m lucky...

We started making a hole in the wall for ("thing that evacuates welding fumes" how`s this called?):

Exhaust vent.

Thanks for sharing amigo.

Exhaust vent.


Thanks but i think the word i was looking for is fume exhauster:

http://up.picr.de/9925270wjh.jpg

Also ran a air hose down in my shop:

http://up.picr.de/9925269cgu.jpg

I didn`t get the steel today, so i got the axles ready. I`m going to use the rear axle in the front car and the front axle in the rear car. The drive sprocket fit`s perfect:

http://up.picr.de/9925241cwu.jpg

http://up.picr.de/9925256voi.jpg

http://up.picr.de/9925264xqm.jpg

I`m going to finish the front car first and make a simple skid steer mock up with the parking brake, so i`m able to test drive the front car itself...
I also decided to get a small trailer to transport the front car. The rear car will go in my van...

nice fab work, always cool to see projects from other countries.

try fume extractor:

http://www.mist-dust-collection.com/fume-extraction/extension-arms_Flexair.htm

Came up with a new design for the joint between both cars. It`s based on the real one and should be a lot better than my old design:

http://up.picr.de/9944124wle.jpg

All the license plates over the have UL on them?

The first letters are different, depending on where you live. I live in Ulm, so it's UL. If you live in Stuttgart it's S and so on...
The other characters are based on chance(?)...

Finally got my steel today:

http://up.picr.de/9954911rzz.jpg

And started over:

http://up.picr.de/9954892nbq.jpg

http://up.picr.de/9954896apl.jpg

http://up.picr.de/9954898nlq.jpg

http://up.picr.de/9954926qlg.jpg

Unfortunately it warped while welding, so i have to cut it off and redo it tomorrow... :coffee:

http://up.picr.de/9954939icw.jpg

Redid the part from yesterday:

http://up.picr.de/9963806yup.jpg

Then i started with the second one:

http://up.picr.de/9963810zho.jpg

http://up.picr.de/9963813cqx.jpg

http://up.picr.de/9963812xkq.jpg

Both finished:

http://up.picr.de/9963817jrm.jpg

Figured out the final dimensions and engine position today. Also shortened the drive shafts:

http://up.picr.de/9974962smt.jpg

http://up.picr.de/9974967zrv.jpg

Then i started with the frame:

http://up.picr.de/9974969lpi.jpg

And started machining the second drive sprocket:

http://up.picr.de/9974965zxl.jpg

Big change of plans today:

Engine/Drivetrain:
I wan`t happy with the engine position all the time. The center of gravity is way to much up front, the aperture angle is incredible bad for a tracked vehicle. And the drivers view is really obstructed by the big engine...
So i decided to put the engine all the way back in the front car and built a chain setup to the drive sprockets. I think this is a lot better...

Suspension:
It`s not a really good idea to built a vehicle without any type of suspension. The real Hägglund uses two leaf springs to hold the track assemblies and the chassis together:

http://up.picr.de/9982550ajg.jpg

Not much to say, i`ll do it the same way...

Almost finished one track assembly today:

http://up.picr.de/9991697rjv.jpg

http://up.picr.de/9991706cgw.jpg

http://up.picr.de/9991707jfn.jpg

http://up.picr.de/9991729njn.jpg

http://up.picr.de/9991736grg.jpg

Just had to take a seat....

http://up.picr.de/9991739qhf.jpg

http://up.picr.de/9991742zsu.jpg

So much better than before...

First i finished both track assemblies today:

http://up.picr.de/10001499ox.jpg

http://up.picr.de/10001501fl.jpg

Then i started with the main chassis beam:

http://up.picr.de/10001512lz.jpg

http://up.picr.de/10001502at.jpg

This is how it`ll be mounted:

http://up.picr.de/10001515uu.jpg

Placed all the stuff. Space is tight, but everything will fit...

http://up.picr.de/10001517nz.jpg

http://up.picr.de/10001518lr.jpg

http://up.picr.de/10001520py.jpg

Here`s another pic of the track assembly:

http://up.picr.de/10009214wc.jpg

Also started with the second track:

http://up.picr.de/10009239po.jpg

starting to look like something there.

It looks like the motor is sitting on the factory subframe. Are you planning on reusing that or building a custom piece to support the motor and radiator? Worried about cooling with the radiator in the back?

Yes, i`m reusing the factory subframe. Saves me a lot of time making the lower engine/tranny mounts. I just need to tie it into my frame and built the two upper engine mounts...

I don`t think there will be cooling issues, the engine shoiuldn`t be under heavy load...

Tied the subframe into the main chassis beam today:

http://up.picr.de/10035259st.jpg

http://up.picr.de/10035238ek.jpg

http://up.picr.de/10035246ee.jpg

Still thinking about how i`m going to tie the upper mounts into the frame. Maybe you guys have some suggestions?

Also got the bearings for the cv shafts:

http://up.picr.de/10035256ne.jpg

Got the small one painted on sunday:

http://up.picr.de/10009236ad.jpg

We still couldn`t figure out how the articulated joint between both cars works. Because of this we took a ride to a ski resort where i know there`s a Hägglund in use. We looked at it and tried to figure out how it works but we still couldn`t. I looked for the owner and asked him how this think works. He tried to explain it, but couldn`t figure it out himself. So he drove it right over the next ditch, so it would articulate. Then we had a look and finally saw how this works:

http://up.picr.de/10061297qp.jpg

Looks like the bearings of the rear joint are some sort of rubber bushings:

http://up.picr.de/10061315nb.jpg

But the joint itself takes the most movement, you can see it here:

http://up.picr.de/10061319um.jpg

Kind of hard to figure this out if the car isn`t articulated... :eek:

Started the cage today:

http://up.picr.de/10074109rz.jpg

First i made the window frame, to get the exact width:

http://up.picr.de/10074106bk.jpg

With this measurement i could start with the cage:

http://up.picr.de/10074101st.jpg

My saw spilled cooling fluid all over the place, so i made this thing:

http://up.picr.de/10074099dt.jpg

Almost finished:

http://up.picr.de/10074110hb.jpg

http://up.picr.de/10074112tq.jpg

Not sure why it looks like crap on those pictures but it`s all square and how it should be...

As much as it's overused as a joke on this site, I really have to say that it does indeed need more triangulation if you plan on that being a roll cage and not just something to frame up the body with.

I totally agree with you. It`s not finished yet...

But i won`t overdo it, it just weights a few hundred pounds and the chances that i`m really going to roll it are very low...
So it`s mostly something to frame up the body with that doubles as a bit of protection...

I was planning on two more crossbars, one above the window frame and one on the rear. I think this should be enough, isn`t it?

Made some body sheets out of cardboard to check the space on the inside. It`s more than enough just not where it`s needed. But i`ll find a way to figure it out...

http://up.picr.de/10082914eo.jpg

http://up.picr.de/10082918fa.jpg

The radiator fit`s besides the engine:

http://up.picr.de/10082942uy.jpg

Besides the seat is a lot of room for the controls, electrics and stuff...

http://up.picr.de/10082939ta.jpg

Starting to look like something now. Looks good

i was skeptical at first, but this is turning out to be a great project! i like it.

one question: is there going to be any sort of firewall between you and the engine?

Put the wiring loom back together to see if it fit`s or if i have to lengthen it:

http://up.picr.de/10095780eo.jpg

http://up.picr.de/10095789wg.jpg

It seems to fit except of a few small things like the wiper or a few lights...

i was skeptical at first, but this is turning out to be a great project! i like it.

one question: is there going to be any sort of firewall between you and the engine?

Thanks. I`m planning on build a full enclosure around the engine and radiator. Basically from behind the drivers seat to the rear. Don`t like the idea of an exploding radiator behind me... :eek:

ok, that makes sense.

i'll just wait for the pictures and enjoy the build. carry on!

Thanks. I`m planning on build a full enclosure around the engine and radiator. Basically from behind the drivers seat to the rear. Don`t like the idea of an exploding radiator behind me... :eek:

You going to try and use the hot air for heat in the cabin?

I thought about that, but there`s so much room at the inside, i`ll just use the heater and stuff from the car... :smokin:

Got some consumables today, so i can continue working:

http://up.picr.de/10109801wc.jpg

Also got the leaf spring:

http://up.picr.de/10109809dr.jpg

This is how i`ll mount the rear one. Of course at the right angle:

http://up.picr.de/10109825fd.jpg

First i bought some steel today:

http://up.picr.de/10121031fo.jpg

Then i started with the spring mounts:

http://up.picr.de/10121020fe.jpg

This is how they`ll look. Still a lot of bracing to do:

http://up.picr.de/10121037dk.jpg

http://up.picr.de/10121041xi.jpg

Also figured out a way to mount the clutch pedal. I even can use the oem cable:

http://up.picr.de/10121039pd.jpg

http://up.picr.de/10121046ur.jpg

http://up.picr.de/10121047ij.jpg

Tacked together the rear spring mount and put the weight on it. Seems the angle is not much off, it could be about right when all the weight is on it...

http://up.picr.de/10128954db.jpg

http://up.picr.de/10128959wx.jpg

Got a lot of stuff done today. First we mounted the leaf springs:

http://up.picr.de/10149326rs.jpg

Bent up some ubolts:

http://up.picr.de/10149352nc.jpg

http://up.picr.de/10149393te.jpg

And it`s finally sitting on it`s own weight:

http://up.picr.de/10149403mt.jpg

http://up.picr.de/10149433an.jpg

And a suspension test:

http://www.youtube.com/watch?v=Yf09nc_gZPQ&list=UU1xBZ9_xJdm5_1Ph3OzZ2WQ&index=1&feature=plcp

Started over with the engine mounts:

http://up.picr.de/10149453ma.jpg

http://up.picr.de/10149447zb.jpg

http://up.picr.de/10149474if.jpg

Also mounted the bearings for the driveshafts so i can order the chains tomorrow...

http://up.picr.de/10149476oi.jpg

http://up.picr.de/10149507wf.jpg

http://up.picr.de/10149510os.jpg

http://up.picr.de/10149523zv.jpg

http://up.picr.de/10149533tk.jpg

wow crazy work.
I am very interested to see this thing in action.
Keep up the amazing work!

Impressive engineering.

Maybe you guys have a better quality of threaded rod over there but around here seeing it in use on a project is an instant and obvious sign of a death trap. :D

Maybe you guys have a better quality of threaded rod over there but around here seeing it in use on a project is an instant and obvious sign of a death trap. :D

:laughing: I don't think the Mini Hägglund will be moving very fast:laughing: Unless maybe he comes up with some beafy-er tracks.

LOL @ the suspension test

i'm waiting for this to be in the epic fail thread. i just don't see this working at all. prove me wrong though. please! :(

Maybe you guys have a better quality of threaded rod over there but around here seeing it in use on a project is an instant and obvious sign of a death trap. :D

It`s just the standard grade 8 stuff. It won`t be moving fast, it weights a lot less than a car, so i don`t see any problems there...


i'm waiting for this to be in the epic fail thread. i just don't see this working at all. prove me wrong though. please! :(

Well, the only thing that i`m not sure if it`s working are the tracks. If they don`t work, i`ll come up with another design. The rest of the stuff doesn`t need to be changed with other tracks, so this will be fine...
Be sure that i`ll prove you wrong. I won`t stop until this thing is working properly... :flipoff2:

I'm not sure why you decided to support the CV axle with a bearing block. the axles do not need support. Maybe I'm missing something there, but that's usually how CV axles work. I realize you probably don't have a tube bender or notcher, that would really help you with your cage design and clean the look up much more. The flat stock you used to hold the bearing block in place is going to bend as soon as any torque is applied.

I take it you are using the pipe on the front of the subframe to support something. i think i'd tie it in better or use something a little more structural there.

I think your tire choice is not going to work. since they have a round profile instead of a flat profile i think the track is going to wonder off. I don't see how the tracks will ever stay on for more then a few feet and then you'll have to field repair it every few feet.

I've operated track hoes / excavators, and there is a lot of stress on the tracks when you try turning. I'd take a look at those more closely to help in your track design. you'll also notice on tanks the suspension is built into the track wheels, not the body. The body could lean over into the tracks on a side hill.

I think it could be cool and work well.

Does the transmission / transfercase have differential in it? Are you going to have to weld the differential in the transfercase to get it to work right?

I'm not sure why you decided to support the CV axle with a bearing block. the axles do not need support. Maybe I'm missing something there, but that's usually how CV axles work. I realize you probably don't have a tube bender or notcher, that would really help you with your cage design and clean the look up much more. The flat stock you used to hold the bearing block in place is going to bend as soon as any torque is applied.

I take it you are using the pipe on the front of the subframe to support something. i think i'd tie it in better or use something a little more structural there.

I think your tire choice is not going to work. since they have a round profile instead of a flat profile i think the track is going to wonder off. I don't see how the tracks will ever stay on for more then a few feet and then you'll have to field repair it every few feet.

I've operated track hoes / excavators, and there is a lot of stress on the tracks when you try turning. I'd take a look at those more closely to help in your track design. you'll also notice on tanks the suspension is built into the track wheels, not the body. The body could lean over into the tracks on a side hill.

I think it could be cool and work well.

Does the transmission / transfercase have differential in it? Are you going to have to weld the differential in the transfercase to get it to work right?

The cv-shaft is supported because the chain sprocket is mounted there. The mount is not finished yet. When everything`s tacked together and finished i`ll pull it apart and weld everything up. I`ll add gussets too...

I`m not sure what you are talking about the tires and their profile. I`ll just try if the tracks work or not and then start over if it doesn`t work.

The body can`t lean into the tracks, because there are bumpstops built into the spring perches...

The transfercase doesn`t have a differential. But i`ll weld both diffs when it`s finished...

I agree that the bracket holding the bearing is going to bend easily. Why did you not just connect the axles directly to the drive sprockets? I'd hold off on welding the diffs until it's complete and working. If you have problems getting the articulated joint working, you could always just run the front part as a little tracked buddy and use some sort of brake to turn with the open diff.

It`s just not possible to connect the axles to the drive sprockets. I could do it, but then i`d have about 5" of ground clearance...

Yes, welding the diffs is the last thing i`ll do. For test driving i`ll connect the parking brake cables to some levers, so i can drive the front car with skid/brake steer...

Have you considered hydraulic motors as drives Dow the tracks. There would be much less moving parts. Using a small 3 or 4 cylinder diesel to power all the hydraulic motors would be cleaner and easier.

Valving could get the speed you want.

Running the controls through a hydraulic setup would be much easier as well.

Yes, but that costs a lot of money. And i don`t have a lot of money... :(

There`s already a bulletproof Plan B for everything. But i started it this way and want to see if it works or not. Then i decide what to do next...

Well, I hope it works.

I've found sometimes you spend more money trying to be cheap, then if you just are patient and save some pennies for the right parts. I've built 3 different jeeps to get to the point I realized I was wasting money trying to make them what I wanted. Then I found a Range Rover that was more capable for my needs then any jeep would ever be. I wasted a lot of money on those three different jeeps instead of just really knowing what i wanted.

You`re indeed right. But if the tracks don`t work, i probably wasted around $50. Same for the chain drive...

So i don`t think it`s bad to try stuff that will maybe fail as long as i have fun and i`m learning... :smokin:

Mounted the radiator and overflow tank today:

http://up.picr.de/10178039je.jpg

http://up.picr.de/10178043wi.jpg

Won`t be easy to get it plumbed, and i`m missing some ideas right now...

so, i'm looking through, and now i have a question:

what kind of drive system are you using? i'm not familliar with skid-steer systems

This won`t be skid steer. It`ll be articulated steering with a hydraulik ram between both cars...

Drive will be via chains in the front and with a differential in the rear car. They`re connected with an driveshaft...

cool, got it. thanks

looking good.

Put in a new valve cover gasket. The engine looks great on the inside:

http://up.picr.de/10188623tn.jpg

Then i started with the exhaust:

http://up.picr.de/10188625bn.jpg

http://up.picr.de/10188621jv.jpg

It even is a Subaru exhaust... :lmao:

Finished the exhaust today:

http://up.picr.de/10199509sh.jpg

http://up.picr.de/10199523rw.jpg

http://up.picr.de/10199527tq.jpg

I`ve never welded a thin wall tube (0,65mm) like this before, but the weld looks ok:

http://up.picr.de/10199529ht.jpg

Everything welded up:

http://up.picr.de/10199525yz.jpg

Got the chains and sprockets today. This is some serious stuff...

http://up.picr.de/10207924om.jpg

Just have to drill them on the lathe tomorrow...

Then i thought about the shifter linkage:

http://up.picr.de/10207928ny.jpg

http://up.picr.de/10207929uz.jpg

http://up.picr.de/10207931nu.jpg

I think i could use some help there... :confused:

Put everything on it`s place today:

http://up.picr.de/10218462cc.jpg

Then i started with the chains:

http://up.picr.de/10218463zd.jpg

Then i started with the two missing struts:

http://up.picr.de/10218461jg.jpg

Right side finished:

http://up.picr.de/10218465of.jpg

First i pulled everything apart today:

http://up.picr.de/10232503nm.jpg

http://up.picr.de/10232506xn.jpg

Then i started welding:

http://up.picr.de/10232508tb.jpg

http://up.picr.de/10232512lf.jpg

Had to take a break a few times:

http://up.picr.de/10232538rp.jpg

More welding:

http://up.picr.de/10232519gn.jpg

http://up.picr.de/10232536ih.jpg

http://up.picr.de/10232542hs.jpg

One track assembly almost finished:

http://up.picr.de/10232558kj.jpg

Finished

http://up.picr.de/10232559sf.jpg

Everything ready to get back together:

http://up.picr.de/10232579bg.jpg

Finished:

http://up.picr.de/10232583ia.jpg

http://up.picr.de/10232586gs.jpg

My neighbor made an exhaust flap while i was welding:

http://up.picr.de/10232591nx.jpg

http://up.picr.de/10232595xp.jpg

http://up.picr.de/10232602nv.jpg

http://up.picr.de/10232603kf.jpg

Nice work for an 12-year old...

Finished up the radiator plumbing today:

http://up.picr.de/10240311au.jpg

http://up.picr.de/10240320um.jpg

Die Heizung hab ich für`s erste überbrückt:

http://up.picr.de/10240319lv.jpg

Also started reconnecting the vacuum hoses and stuff. I`m really debating if i should just get rid of the charcoal canister and stuff...

I would make the plumbing as simple as possible... less to go wrong when you are out exploring with it...

I would make the plumbing as simple as possible... less to go wrong when you are out exploring with it...
^^ i agree with this
Finished up the radiator plumbing today:
...
Die Heizung hab ich für`s erste überbrückt
...

so you're not putting in a heater? or will the heat from the engine be plenty?

Wow!

so you're not putting in a heater? or will the heat from the engine be plenty?

I'll put in a heater but for now i just bypassed the hoses...

There shouldn't be much heat from the engine because it'll be fully enclosed...

Got the sheetmetal for the gas tank yesterday:

http://up.picr.de/10268737gk.jpg

Tacked together:

http://up.picr.de/10268739zb.jpg

And checked the fitment:

http://up.picr.de/10268740he.jpg

http://up.picr.de/10268769ly.jpg

Looked good, so i started with the sender for the fuel gage:

http://up.picr.de/10268747ek.jpg

http://up.picr.de/10268749iz.jpg

Flange:

http://up.picr.de/10268756iy.jpg

Plumbing:

http://up.picr.de/10268784dw.jpg

Welded the inside:

http://up.picr.de/10268807td.jpg

Added some baffles:

http://up.picr.de/10268808fi.jpg

Welded the outside:

http://up.picr.de/10268809wi.jpg

cool. do you have an estimate capacity?

Should be about 44l, or 11.6 gal...

Been lurking in this thread for awhile now, it's really looking good, keep up the good work :)

looks awesome, can't wait to see it running

Thanks man, me too...

Finished the gas tank and seat mount today. First i finished welding the tank:

http://up.picr.de/10279770jo.jpg

Then i placed it in the chassis and made some mounts:

http://up.picr.de/10279790pb.jpg

The filler neck fits perfect, i just have to shorten it:

http://up.picr.de/10279806fl.jpg

Then i started measuring for seat height:

http://up.picr.de/10279844ia.jpg

And started fabbing some mounts:

http://up.picr.de/10279836cy.jpg

Mocked up:

http://up.picr.de/10279845ej.jpg

And welded everything:

http://up.picr.de/10279920up.jpg

http://up.picr.de/10279922gb.jpg

Looks like i could be able to test drive it saturday or monday...

Maybe you have already done it but I would leak test that tank with water or pressurized air before filling it with fuel, especially if it's mounted under the seat.

Was tested with about 7psi... :smokin:

First i mounted the tank and seat:

http://up.picr.de/10288358fl.jpg

Then i started with some sheetmetal:

http://up.picr.de/10288359za.jpg

http://up.picr.de/10288356aw.jpg

http://up.picr.de/10288357ni.jpg[/QUOTE]

Dieses Projekt wird gut voran

Mini Hägglund first start - YouTube (http://www.youtube.com/watch?v=iok8i1lz41Q)

I`m back in the shop...

Mini Hägglund first start - YouTube (http://www.youtube.com/watch?v=iok8i1lz41Q)

I`m back in the shop...

nice. i'll bet that's a good feeling

very very cool
good work!

Thanks guys. It`s an awesome feeling to have it running... :)

Here`s the missing update. First i finished the right hand side sheetmetal mount:

http://up.picr.de/10307661km.jpg

Then i plumbed the fuel pump and filter:

http://up.picr.de/10307666ct.jpg

Welded the sprockets:

http://up.picr.de/10307698qz.jpg

http://up.picr.de/10307702qu.jpg

A long list to work:

http://up.picr.de/10307712qk.jpg

Clutch pedal:

http://up.picr.de/10307730hv.jpg

Windshield and gauge cluster:

http://up.picr.de/10307742lw.jpg

Then the fun begins. All that electrical crap has to go in:

http://up.picr.de/10307744yb.jpg

Everything plugged in. I`m going to clean that up tomorrow:

http://up.picr.de/10307760of.jpg

http://up.picr.de/10307765zm.jpg

Then i could start it, as seen on the video. It runs fine, except of some leaking oil. I`ll have to take a look where it comes from tomorrow...

Then i started with the temporary brake steering:

http://up.picr.de/10307771rw.jpg

http://up.picr.de/10307774pv.jpg

The list looks a lot better now:

http://up.picr.de/10307773ts.jpg

I`m going to test drive it tomorrow. Can`t wait to see what works and what not...

That fuel tank looks very close to the exhaust manifold. Not going to :nuke: is it?

so you finished both tracks?

remember no :smokin: while driving. :eek:

Mini Hägglund first start - YouTube (http://www.youtube.com/watch?v=iok8i1lz41Q)

I`m back in the shop...

your flapper needs a counterweight.

I badly want to see this thing in action. Shit's rad.

Here`s the Update about the last 3 days. First i finished the second drive sprocket :

http://up.picr.de/10336950af.jpg

Then i made the track tensioners:

http://up.picr.de/10336956xs.jpg

http://up.picr.de/10336971na.jpg

And put on the first track:

http://up.picr.de/10336972cj.jpg

Finished the second track:

http://up.picr.de/10336976dr.jpg

And put it on:

http://up.picr.de/10336979cv.jpg

Then it was time for the first drive. So i put it in gear, sat in the drivers seat, pressed down the clutch and started it. Unfortunately the clutch didn`t work, so it started driving and i was going in direction of our wintergarten. Luckily i could kill it just before i hit something...
So the next day i put the transmission apart und fixed the clutch:

http://up.picr.de/10336987qi.jpg

Then i kept testing it, and shortened the tracks to the right size:

http://up.picr.de/10336981cl.jpg

It wouldn`t work, so i put on some guides:

http://up.picr.de/10336989xm.jpg

Then it really started to work. I could drive a bit and the tracks wouldn`t come off. Unfortunately one of the screws punctured a tire when we wanted to take some videos. But i got it on video when the tires was punctured and how i drove back into the shop:

http://www.youtube.com/watch?v=zPwECZgZvL0

http://www.youtube.com/watch?v=rbEJnHGUO8s

So i`m going to buy some rubber wheels or try to put some foam or something in the ones i have. Any suggestions?

Mini Hägglund first drive - YouTube (http://www.youtube.com/watch?v=zPwECZgZvL0)
Mini Hägglund first drive - YouTube (http://www.youtube.com/watch?v=rbEJnHGUO8s)

So i`m going to buy some rubber wheels or try to put some foam or something in the ones i have. Any suggestions?

Do you need to use rubber? Can you just use a rim or something? Metal would wear a lot slower than rubber, and the bolt ends look sharp.

Also maybe think about making runners like on a snowmobile?

one thing i noticed: it looks bouncy. are you planning on adding some shock absorbers?

one thing i noticed: it looks bouncy. are you planning on adding some shock absorbers?

I think it is more of a rocking motion.. it might be geared really tall, ie, no small creaper gear..

I think I would see about lowering the gear ratios in the chain drive to give it a much lower crawl ratio. That should smooth it out a bit and make it a lot less chaotic and jumpy to pull out it. As it is, you will probably never be able to take off without the drive sprockets slipping as is heard in the video and climbing anything will be a huge chore.

Like I said much earlier in the thread, I think the track system really needs a redesign. Using the bolts to drive the tracks was always a bad idea in my opinion. I wonder if you couldn't expand on the chain drive idea and use two heavy chains with welded crossbars as tracks with normal chain drive sprockets. That would be a lot more "tank-like" and probably a lot more reliable if the chain used were able to handle the stress. Just a thought.

I think it is more of a rocking motion.. it might be geared really tall, ie, no small creaper gear..

yeah, i meant to specify shocks like this: /--\
on either side from the body to the track assemblies. and lower gears would be better, imho, but it works for now

I think it is more of a rocking motion.. it might be geared really tall, ie, no small creaper gear..

It`s possible that i was in third gear, i`m not sure. Overall ratio should be pretty low with those small drive sprockets...
I`m also not used to the controls, so i probably used a lot too much gas...

I think I would see about lowering the gear ratios in the chain drive to give it a much lower crawl ratio. That should smooth it out a bit and make it a lot less chaotic and jumpy to pull out it. As it is, you will probably never be able to take off without the drive sprockets slipping as is heard in the video and climbing anything will be a huge chore.

Like I said much earlier in the thread, I think the track system really needs a redesign. Using the bolts to drive the tracks was always a bad idea in my opinion. I wonder if you couldn't expand on the chain drive idea and use two heavy chains with welded crossbars as tracks with normal chain drive sprockets. That would be a lot more "tank-like" and probably a lot more reliable if the chain used were able to handle the stress. Just a thought.

That sound is not from a slipping sprocket. There`s absolutely no slip at the drive sprockets. There wasn`t even slip with the the blown tire when the tension was way too loose...
The sound is just the sprocket hitting the bolts...

As said before, if those tracks won`t work i`ll go with a snow cat design. Two rubber strips connected by some u-stock with grousers on the inside.
But i feel like those are going to work after all the testing i`ve done...

The chain drive has to be at a 1:1 ratio, otherwise i can`t drive the rear car, because there won`t be a chain drive...

If it makes that much noise hitting the bolts, I'd say that something isn't space quite right. If they hit that hard or have that much interference, there is a good chance something will break when it binds.

There`s metal on metal, there has to be some noise...

What i`m looking for now is something to pour into the tires to make them solid. I could buy some solid rubber wheels, but before i want to try it...
I thought about something like foam, but i think it`s not strong enough. I could even put some concrete into it, but i don`t like that idea... :shaking:

Either way I think you are still going to have a puncturing issue with the tires. Even if they were solid, they would still get chewed up badly since the wear surface is still going to be soft rubber.

I want just something to try it before i order the solid rubber wheels...

Ok, so i started thinking about some real tracks today. My favorite would be the snowcat style. Some conveyor belt, u-stock and grousers on the inside. I could make the front ones a bit wider, and the rear ones almost as wide as the car. This would help to reduce ground pressure...

The only downside i see is that it`ll be a pain in the ass to make it, and that i can`t drive on the street with this style tracks...

Would be nice too hear some thoughts...

Would be nice too hear some thoughts...

Do you need to have rubber on the wheels? Why can't you just use a big rim or something similar?

I don't understand the need for rubber tires, inflated or not. The thing is going to be on snow, and mostly at relatively slow speeds too. It would be like dozers and other tracked vehicles.

I think it would be an easy solution to keep you going with what you have.

Am I missing something?

Rubber, polyurethane or something similar is sort of necessary as a wear surface and to give a little cushion. Metal to metal contact on the rollers would make a lot of noise, make the ride very rough and would wear the tracks and rollers very quickly. That can be acceptable in construction type machinery but I have a feeling the OP is going to want to go a bit faster than a typical track loader.

You`re right Elwenil. One of the reasons i ditched my tracks is that i don`t feel comfortable going fast with them...

Food for thought?

http://www.pirate4x4.com/forum/attachment.php?attachmentid=668994&stc=1&d=1335752688

That`s an excavator rubber track. I looked into them, but they`re pretty expensive...

I think i`m sold on the snowcat style. I don`t really have to drive it on the street, i just would`ve been nice...

I like the Thiokol design, because the side guides and the grousers are one part, so that would save a lot of time. But i have no idea how to fabricate them...

I was thinking more about the suspension, track tensioners and hubs more than the track design. I like the SnowCat tracks idea also.

I won`t change anything about the suspension yet. But we can collect some ideas, so i can build the rear car with an updated design...

Now i need some ideas on how to fabricate the grousers. I need about 200pcs. of them... :eek:

So, i need 200 of those:

http://up.picr.de/10360990eg.jpg


Anyone has an idea how to make them?

I think it'd be cheaper in the long run to just purchase a snowmobile and be done.

Is this what this site is about? Purchasing finished vehicles? :eek:

Still only a few hundred $$ into this, not going to be much more until i start the rear car...

Well if you had lots of time, lots of square tubing and a jig for a hydraulic press you should be able to pump out a few of those an hour. The good news is that you really won't need them made to SnowCat specs since you are much smaller and lighter which should make the bending process a lot easier. I suppose one could also use a small bending jig to make them depending on the strength of the material you end up using. It would take a few steps to get to the finished product but you have shown that you are pretty resourceful so I don't think it would be beyond your abilities. It will take a fairly long time to make that many pieces though but at least you will be able to make spares for repairs in the future, lol. :D

Well, that`s what i thought too. I have quite a bit of time, and access to a press too. Tubing can be bought...

I`ve never made a die, is there a how to or something like this around?

I thought about using 20x20x1,5mm tubing, that should probably be strong enough. I could even build a small press, i don`t think there`s that much force needed to bend that tubing...

I have a bit of conveyor belt and some tubing laying around, i think i`ll put something together tomorrow...

The die or form wouldn't be that hard to fabricate. Since the tubing is square you would need a form that would fit somewhat close on the sides to keep the tubing from collapsing. Naturally you would need a recess in the middle and the top form would need a protrusion with the correct clearances to make the bends and not crush the tubing. You may find it easier to cut and weld up a mock-up piece to build the form around.

Alternatively you could just weld up all of the pieces. Your welding looks pretty good so I think that might be good for this application, though it may cost more int he long run considering the welding wire and shield gas. Still, with the way the parts are made, the recess looks to be about the same size as the tubing itself so you could cut the pieces at 45° angles and just stack two ends over a shorter middle piece and weld them together to make the same part. In some ways it may be quicker and more reliable since you can set your saw up with a stop to cut multiple pieces over and over again and then set it up for the next part and cut those. Then once the parts are cut, a wooden or metal jig could be made to set the parts in for welding to make sure all the parts are identical. In essence, you will have a small assembly line going, lol.

I`m going to built a test grouser tomorrow, and then try to built a form to press it...

I like the welded construction a bit more, i think it`ll be stronger. But, i`d have to cut 1000 pieces and weld them up, this is going to take some time. Would be much easier to just cut 200 pieces and put them on the press...

I think i`ll start a thread at General4x4 and ask how the other guys would do this...

Made a prototype grouser today:

http://up.picr.de/10388160af.jpg

http://up.picr.de/10388171iy.jpg

http://up.picr.de/10388184xx.jpg

http://up.picr.de/10388170qq.jpg

http://up.picr.de/10388179hi.jpg

What do you guys think? Is it worth trying to build a form?

Why so deep?

Because i want it to be bulletproof... :smokin:

Because i want it to be bulletproof... :smokin:

if you could make it shorter you could use a thicker cross section of box tube, cut it @ a 45, then just flip the pieces and run 2 weld beads to join them.

much easier to manufacturer.

Sorry i don`t get it. Could you please draw something up or so?

Here`s the grouser design that i`ll be building:

http://up.picr.de/10415321wx.jpg

http://up.picr.de/10415334ct.jpg

http://up.picr.de/10415337tv.jpg

Careful with those points sticking up. If the track starts to slip, and it will, you are going to pop another tire in a hurry.

Yeah, i should cut the angle the other way, so it`s flat on top... :smokin:

If you're wanting the tire to serve as a guide to keep the track centered, you'll probably want those bars more perpendicular. As they are now, the tire will ride up on them...especially when you are turning or riding along the side of an incline. Just like anything else, once you get it running you'll see other areas that will need attention. BTW, that's a neat project you have there :smokin:

Yea, i should probably do that... Any thoughts on how much? Anything like 60-70 degrees? Should sit at 50 now...

Yea, i should probably do that... Any thoughts on how much? Anything like 60-70 degrees? Should sit at 50 now...
I'd probably say 70 or better. If you have a chance to see some over-the-tire track systems for skid steer machines, it will help you get an idea of how you might want to proceed with yours. Here's a link
http://www.everythingattachments.com/skid-steer-over-the-tire-tracks-s/8406.htm

bump for an update.

making piles o grousers?

I wish i would...

I`v been working on my van the last week and then spent the weekend at the offroad event where i wanted to test drive the Hägglund. Oh well, it was fun, even without the Hägglund:

http://up.picr.de/10553759ug.jpg

But, i bought a nice drill that i`m going to pick up tomorrow. Should speed up the progress of drilling the 1600 holes for the tracks...

http://i.ebayimg.com/00/s/MTAyNFg3Njg=/$(KGrHqFHJC8E92QdB,1yBPpksSJ23Q~~48_20.JPG

I`m also going to get a quote on the steel that is needed for the grousers...

One thing you may consider when trying to get a better price on some steel is ask around to other people you know that are buying steel and buy more at once. The more weight you buy the cheaper it is. Also, buying full lengths is cheaper than getting saw cut to size. Or, ask them for drops. When people buy say 8 ft of a 12' random length bar they are charged the full length price plus the saw cutting fee. They will then scrap off the remaining 4' or sell it off at a discounted price (usually scrap price plus some %).

Great little project you have going though

I need about 400ft of pipe, so there`s no other way than buy full lenghts. But i can order them at work, so i don`t pay much...

I started working on the Hägglund again today. First i set it at ride height and put on one of the last few missing tubes:

http://up.picr.de/10588841ip.jpg

Then i started cleaning up the wiring mess and place all the switches and fuses and electrical stuff:

http://up.picr.de/10588848oj.jpg

http://up.picr.de/10588849yf.jpg

Prepping the ammo can for the ecu:

http://up.picr.de/10588840ro.jpg

Everything together. It`s a lot cleaner now:

http://up.picr.de/10588850zs.jpg

Also ordered about 170ft of square piping for the grousers...