getting ready to do the belly plate on my heep. gonna be a big fawker, from the bell housing to the fuel cell with provisions for drivelines.

So is 3/16" plate enough? I dont really want to bolt a 150# chunk of 1/4" down there but i do want it to be stout.

What are you all running?

3/16 is fine with bracing.

I ran 1/4" before and that bitch was just too heavy.

I think i've seen some pics of either the cambell ent buggies or some body elses upside down and the whole underside was skidplated like sceep is talking about doing but whatever it was
was all shiny. I dunno what it was ??? anybody else remember those pics ...

- jack

Ask Tony from rock equipment what material one of his club members is using, it was thick but non metal, stout but not heavy.
Rich

Originally posted by Big Rich
Ask Tony from rock equipment what material one of his club members is using, it was thick but non metal, stout but not heavy.
Rich

is this some kind of riddle?? lol hmm.. wonder if hes using a plastic of some kind.

Originally posted by sceep


is this some kind of riddle?? lol hmm.. wonder if hes using a plastic of some kind.

No:rolleyes: not a riddle. I was not going to guess as to what type of material it is EXACTLY. :flipoff2: :D

Rich

could you use 3/16 plate and x brake it from one corner to the other end opposite corner.
get it bent just enuf to kink it, maybe 5 degree's or so.
any fab shop would do it for ya I would think.

I don't know , just a thought.

I know several guys running an alum. skid plate - its a hardened alloy and used a lot in the mining industry. Can't remember the designation, I'll try to find it out- but I do remember that it was fricken expensive - about 1/3 the weight of steel, but ~5 times as expensive..

I'm running a 3/16" steel skid with some angle steel welded on for re-inforcement, works great so far...

Even 1/4" is not strong enough with out bracing. Use 3/16" and put several braces perpendicular to the frame rails. Bracing in that manner will handle the loads, and shock better than a "x" brace for a cross member. 1" square tubing works well to stiffen the cross member.

Ben

Not to dog on your idea but why not make it two piece? If anything the one piece is gonna be heavy and damn cumbersome to drop by yourself. Besides, by the time you brace the 3/16, it's gonna way almost as much as the 1/4... Just a thought...:D

Originally posted by Peabody
Not to dog on your idea but why not make it two piece? If anything the one piece is gonna be heavy and damn cumbersome to drop by yourself. Besides, by the time you brace the 3/16, it's gonna way almost as much as the 1/4... Just a thought...:D

no reason. that i can think of, and it probably will end up being 2 piece as my damn tranny pan ended up about 1/4" below the frame so i have to either drop the whole thing a bit or drop the front 1/2 a little. dunno yet.. just sittin here @ work brainstorming. ;)

There was a thread in the jeep section about this. Someone reccomended an aluminum skid with a steel skin....Run like 1/4" aluminum with a 14 or 10 ga steel skin....so the al doesn't gouge....interesting idea.

You would need to run some sort of barrier between the two metals or you would end up with a rusted pile in short time. Galvanic response between the two metals would be bad.

I used 1/4" with some reinforcements, I haven't weighed mine but it is far from light but I can remove install it by myself.

http://jeepwrangler.info/Tech/ARMOR/Flat_skid_Labeled.jpg

On a TJ it goes from the front of the oilpan to the back of the stock muffler.

Originally posted by JEEP_TJ_FREAK
I used 1/4" with some reinforcements, I haven't weighed mine but it is far from light but I can remove install it by myself.

On a TJ it goes from the front of the oilpan to the back of the stock muffler.

that looks great, just what i am gonna do. why did you use the skid for your tranny mount though?? seems like that would make it a pain in the ass to pull the skid without dropping the tranny/tcase/ motor since there's no place to get a jack in to hold it up??

Even with 3/8 steel a flat skid/crossmember will flex considerably with the weight of the vehicle on it. I highly recomend adding lateral verticle trusses on the top side to help counter this inherent rigidity issue.

Originally posted by Big Rich
Ask Tony from rock equipment what material one of his club members is using, it was thick but non metal, stout but not heavy.
Rich

Carbon Fiber? I remember seeing them on the factory NISSAN rally cars. Cool as you could see big nasty scrapes in them from sliding up and over stuff (at speed).

Aluminum.... Aluminum is about 1/3 of the weigh, but you need to increase thickness by 50%. So rather than a 1/4" steel plate, run a 3/8" aluminum plate (which is half the weight of steel). I used the common "diamond plate" on the rally car. Pretty sure it was 6061-T6. Helps to stuff some closed cell foam between the bottom of the oil pan and plate to keep rocks out of there. Nothing worse than rocks getting wedged in, smashing down on something, and having the oil pan pierced by a small rock! :(

I mounted my plate so the front could pivot a little. Lifted up the front, loosely install bolts. Used the floor jack to lift the back up, inserted rear bolts... then tightened up the front. Worked good, and allowed for some play when things get bent so I could still bolt & unbolt it!

All you need between the aluminum and steel is some heavy clear tape! This come up awhile ago, but never had any issue with corrosion. Someone on the list pointed out there is "leading edge tape" for helicopter blades... that worked great for them.

Tom :usa:

Originally posted by jeepboyben
Even 1/4" is not strong enough with out bracing. Use 3/16" and put several braces perpendicular to the frame rails. Bracing in that manner will handle the loads, and shock better than a "x" brace for a cross member. 1" square tubing works well to stiffen the cross member.

Ben

Thats pretty close to mine, I have 1/4in with three 1in box tubes 1/8in walled going perpendicular to the frame. For the cross bracke I have a piece of the box on the back side and piece of 1/4in thick plate welded to the front at an angled so it slids well.

Used diamond plate found "CHEEP" so thump thump thump as I slid, but hasent gotten hung up yet...

Originally posted by sceep


that looks great, just what i am gonna do. why did you use the skid for your tranny mount though?? seems like that would make it a pain in the ass to pull the skid without dropping the tranny/tcase/ motor since there's no place to get a jack in to hold it up??

I am link and coil out back with triangulated lower control arms so I built a crossmember for the links to mount to. When lowering the skid the tailhousing of the transfercase (231) rests on the crossmember.

Else you can wrap a rachet strap around each framerail and under the transfercase to hold it up. Thats what I did to get the original measurments when the crossmember wasn't completed.

Last 5 weeks I have been busting ass on this thing lots or work and rework.

Originally posted by JEEP_TJ_FREAK
I used 1/4" with some reinforcements, I haven't weighed mine but it is far from light but I can remove install it by myself.

http://jeepwrangler.info/Tech/ARMOR/Flat_skid_Labeled.jpg

On a TJ it goes from the front of the oilpan to the back of the stock muffler.

That is freakin' bad :skull: ass!
You got any pics of it installed? Or are you that far along yet? What does it mount to?

Originally posted by ashmanjeepXJ

Thats pretty close to mine, I have 1/4in with three 1in box tubes 1/8in walled going perpendicular to the frame. For the cross bracke I have a piece of the box on the back side and piece of 1/4in thick plate welded to the front at an angled so it slids well.


do you have the 1" square tubes bolted to the skid plate and the skid plate bolted to the frame or how is it all held together ?

- jack

Mines 1/4" with 5/16" angle welded to the sides that is used to bolt it to the frame.

Its heavy yet functional.

Havent put any cross braces on yet...but I plan to...it bends when I jack the jeep up with it.

It's for a CJ...I've since drilled a trans case drain hole, and cut a notch out for the front driveshaft clearance.


:)

I like to keep the weight down. I use 12ga covering 1" 11ga tube. makes for a hellish strong, yet light skid plate. The only down side is it takes a little longer to make.

covered

Bottom

This is for a YJ that has a EFI 302,c4 and D20.

me likey....damn why didnt I just make one like that...oh yeah cuz I'm not creative. :rolleyes:

MJ

nice work ems ... I think i'll make one like that.

don't feel bad MJ ... i don't have creative abilities either ... I just try and find out what somebody else did and do that the best I can :rolleyes:

- jack

i like the tubing idea....light and strong, 1"x.120 should be enough...?

Originally posted by emsoffroad
I like to keep the weight down. I use 12ga covering 1" 11ga tube. makes for a hellish strong, yet light skid plate. The only down side is it takes a little longer to make.

Damn, that's Hella-kewl, now I gotta go re-think my plans, damn, damn, damn.

Nice work.

thats exactly what i'm gonna build for the powerwagon. nice job.:beer:

Nice job ems! :D

:emb3: Thanks

As far as being strong enough, the guy that I made it for had his jeep resting on it and it was fine. You might have a problem if you don't have any bends in it. I know we always had a problem with breaking top tranny supports in the VW rails, untill we made them with a bend instead of straight to the tranny.

I even receased the bolt heads on the mounting rails. This took alot more time then expected, since YJ's have part of the treaded insert sticking out of the bottom of the frame. But in the end it made for a nice setup.

hey ems, when you say some bend in it, you're talking about putting some arch in the tubes that run perpindicular to the frame rails right ?

- jack

I made mine out of 3/16" and after some hard use ... pinwheeling in Cedar City ... I see that I need to add 1" angle iron tent-style across the trailing lip and possably another one across the middle.


http://www.monsterslayer.com/jeep/SkidPlate/AllPaintedUp.jpg

I'm sure glad I didn't use 1/4" because I wouldn't be able to easily lift it back into place.

I used 3/16 and just welded on a section at a 30 degree angle to add strength under the tranny. I also ran a set of parallel supports off the 30 degree angle long the tranny for support up to the bell housing.

We have a guy in our club that used a plastic butcher block.It is I think 1/2" thick.He built some supports and bolted flat to the frame.Everyhing except the butcher block is above the frame.Works really good and is light.He bought it used for like $40 it was a 4 x 6 piece I think.Blazin

butcher block? i gotta check into this. i was figuring out how much mine would weigh and theres no way i'd get it on and off by myself. anyone got pics of a plastic skid and how much bracing they used to make it work without getting destroyed?:beer:

If you run in any serious mud (TTC,... like) a skid plate has to be able to drain out big chunks of slop...they can really drag you down on a trail machine...
a mudbogger or rally buggy should have them tho ...jmho
I really don't want any more skidplate than necessary, the "catch-all effect" is one thing, plus, weight is always an issue, plus having a big ole plate on the bottom of the frame must get in the way when working on something.
I think it is better to use a tube for a X-member, and some skid pads where needed.
I put my battery next to the t-case w/ some tube to protect it and the t-case...it works.
I've had pretty big fires from muddy grass burning on the exhaust at 50 mph. :)

Originally posted by jeepboyben
Even 1/4" is not strong enough with out bracing.

Yup. I used my 1/4" skid the first time without any bracing on a trip to Moab and I bent it pretty good the first day. I've since re-done it to include bracing (1" flat bar and a little angle scrap too). Now it holds up great.

1/4" is heavy. I like it though 'cause my grocery getter has a high COG and any weight down low for me is good. If I was an anorexic bitch like some of you then I'd have done it differently :flipoff2: Keep it as high as possible. I'm going to re-do mine this winter and raise it and tie it into my rocksliders to make the whole underbody flat. I'll prob use 3/16 for the side pieces.

Here's a pic of mine as it was coming together:

(it's nothing fancy, but it gets the job done)

Here's a few more pics I have on my hard drive:

2

3

4

looks good:D

i want to know more about the plastic skids;)

Originally posted by FULLSIZE
looks good:D

i want to know more about the plastic skids;)

Brian, I read about them somewhere. The scoop is they are the same type of material that is used for cutting boards. It's thick plastic (??) stuff that is supposed to work great. The neat thing is the stuff is very slippery for knife blades so when a rock is on the plastic it actually helps slide over the stuff. Then at home, to take out the scratches, just use a regular home iron to smooth it all out. Supposed to work great. Just contact a butcher shop to see if they have old shit or ask for the info on the seller they use for the cutting boards.

Here's my skidplate on my FJ40. Not the prettiest thing out there, but it works well. It's a framework of 3/4 SOLID bar stock with some 3/16 plate for good measure. Might be a bit heavy, but it doesn't even blink when it hits the rocks.

http://user.netomia.com/Box%20Rocket/skidplat.jpg

these are the units I make for Land Cruisers. I use 1/4 plate and make them to custom fit each different tranny application.

rear pic....

thanks curtis:beer:

those are some good lookin skids guys. thanks for fawkin up my whole day!!:flipoff2:

Years ago when I used to build drift boats we would cover the bottom with a UHMW polymer that was used in the lumber industry. This was a plastic about 1/2" thick or so that had a very low co-efficient of friction. If you took your drift boat off the trailer on a boat ramp and it was too steep the sucker would head for the water. We used to winch the boats over cliffs and drag them across the rocks with out any problems, let alone drift over rocks all the time in the river. The difference here is the weight of the vechicle, I'm not sure how it would hold up to sharp rocks. It would probably be okay since your not riding on it all the time. It would require a strong support structure to bear the weight, it sure would be slippery. it would be close to a plastic cutting board in density, but real slick.

Paul

Plastic.........wow, that would be really cool if it would hold up!

I could shave an easy 50 lbs from the buggy by using that!

I want to know more about the plastic too. I am going to have to do some looking around. UHMW plastic is the same thing that winch line is made out of right? If you had a very light tube support for the tranny and t-case the plastic wouldn't have to support any weight.

I would be worried about the exhaust though. That stuff starts to break down at a low temp. I guess you could do a light deflector or something?

Where are the plastic experts when you need them?

plastic sounds pretty awesome, how would like 20mm plastic stack against steel weight wise?

UHMW plastic is the Shit.. I purhased 4x12 sheets for 189.00 at the local plastics house.

Some of the cambel buggys are 1/4 inch aluminum, with a think plastic under that.

There is another guy who drives the discount tire buggy, i think his name was Neil, he used the same plastic as the cambell rigs, and i cannot remember the name of the stuff, but it began with D, and was 500 bucks for a full sheet 4x8. But that was 5/8 thick and it was stout, and he used no metal just plastic.
It resisted against gauling, and he said if it did gouge really bad you could use and iron, like waxing skis, and rub it out. There was a lot of it on his rig, and he said all of it weighed like 25 pounds.

Bad ass.

Ian-

Originally posted by COMPLAINE
I cannot remember the name of the stuff, but it began with DDelrin.

Delrin.

we use this stuff for control arm bushings in road race cars. expensive is all i can say. found a local place that has 1/2" reprocessed uhmw polyethylene for a pretty good price. this is the way i'm goin. same stuff as butcher block just not food grade;)

www.interstateplastics.com

:D

More info please...

How thick and what material would have to be used for a crossmember/belly crossmember to support the weight of say an automatic and atlas?

I found that UHMW is 7 times lighter than steel. But if you have to make a really thick skidplate you loose some of that. I also found a company that can bond UWMW to steel, and you can mold that stuff too.

Back to the top!

i'm gonna use a square tube crossmember to support the weight. the uhmw wont hold the weight. i talked to the guys and they said not to use it for the structural member in our application. just the experts at the manufacture's .02 :D