Gorton tracer mill: Approx. weight?

[LCexplorer]

After finding out the cost of converting my regular knee mill I bought recently to CNC and thinking I may have made a mistake... I lucked out and found this:

http://www.mybackyardjunk.com/gorton1.jpg

It's a Gorton 2-30 tracer mill.

The possible plan is to convert the Gorton to CNC and hopefully be able to digitize the tracer feature.

The question I do have is does anybody have an idea of the weight of this machine? I will probably have to get a Hiab (truck mounted crane) to move it out of it's current location and want to know what capacity crane it requires.

Any general comments and observations about my future Gorton are welcome.

As luck would have my good buddy wants my knee mill, so I am hoping this works out.

[Wicked_S10]

Gortons are very well made machines, but the company is now defunct, and although there is a place that bought the designs and can make any of the parts, they are expensive.

I have a Gorton 0-16a, manual lists it weight at just north of 3k lbs, w/ no tracer head. The 2-30 is much, much bigger than my machine.

Most of the time, tracers are hydraulically operated, and in a lot of cases, they have no x/y screws, just hydraulic cylinders. From the true-trace box in the background, this appears to be hydro too, it has me confused on what appears to be a stepper on the y axis. Maybe a hydro motor?

It may be a good base to start from for CNC conversion. It looks like it has very heavy Box ways, which is an excellent start for cnc. I would try to find out if it has ball screws of acme screws. acme screws are not very desirable for CNC due to high friction and tendency toward lots of back lash. If it has ball screws, they are typically fairly easy to rebuild the ball nuts with off the shelf parts, provided the screw is in good condition. There is a good yahoo group for Gorton owners, they will probably have the manual and some current owners of the same machine that might be able to help you more.

Later,
Jason

[LCexplorer]

Thanks for the info.

At this point I am guessing around 6K lbs, at least that is what I am telling the Hiab guys. She's defiantley big about 7.5 ft tall.

I checked the machine out before laying down a deposit, the X/Y axis and controlled with a hydraulic motors with belt drives attached to ball screws. One cool feature is you can still crank the table manually when you lock in the clutch mechanism. Now I just have to figure out what would be appropriate sized stepper/servo motor would be.

I have applied to the Gorotn Yahoo group and awaiting to hear if I am allowed to be part of the group (moderator controlled). Thanks for the heads up anyways!

[Wicked_S10]

6K would be a fair bet if it is anywhere near the size of my B'port series 2 I dragged home. That bitch was 7.5' tall and has a footprint of approximately 7'x6'. Crated weight listed in the manuals for shipping was just north of 6k lbs IIRC. We had to take it apart in pieces to get her on the trailer. We nearly rolled a big 4x4 loader trying to get it off the ground in one piece.

For motors, my machine had Nema42 series steppers, rated somewhere around 1000 oz/in. From all accounts, they actually fall in closer to 800 oz/in and they have no problem whipping my table around at a pretty good clip, at least for an un enclosed machine. Check out this company, this is where I bought all of my drives: http://www.kelinginc.net/NEMA34Motor.html The second and third steppers listed on that page are very reasonably priced and should be plenty powerful. I am told their steppers are excellent for the price point. You will of course have to adapt them to fit the mill.

If you get obsessed with incredible rapid feeds, and want a closed loop system, look at servos, but it will take a lot more money. Realsquash and I both just completed control retrofits on older CNCs. You can find both threads detailed in this section. His was a servo based machine and mine was stepper. It will give you some good ideas on getting it off the ground. In my case, it turned out to be a shit ton more work than I anticipated, but the machine stayed well inside my budget constraints. I think I have about $2k wrapped up in the whole deal, including the purchase price of the machine.

As for the Gorton forum, they will let about anyone in. It just takes a while for the mod to read the application and punch the button...

Jnutter on here has or at least had a Gorton too. He may know more about this particular machine. Are you going to run both heads on it? I would love to have a uni head for my old gorton, but you are probably way to far away to sell and ship me one :D

Later,
Jason

[Wicked_S10]

Here you go from the Gorton group.

http://www.bbssystem.com/manuals/2-30-mill-manual.pdf

http://www.bbssystem.com/manuals/2-30-maint-parts-manual.pdf

It just happened that they were too large to be hosted on the yahoo group, so they are already linked off site, you should be able to get to them at anytime.

Later,
Jason

[LCexplorer]

6K would be a fair bet if it is anywhere near the size of my B'port series 2 I dragged home. That bitch was 7.5' tall and has a footprint of approximately 7'x6'. Crated weight listed in the manuals for shipping was just north of 6k lbs IIRC. We had to take it apart in pieces to get her on the trailer. We nearly rolled a big 4x4 loader trying to get it off the ground in one piece.

For motors, my machine had Nema42 series steppers, rated somewhere around 1000 oz/in. From all accounts, they actually fall in closer to 800 oz/in and they have no problem whipping my table around at a pretty good clip, at least for an un enclosed machine. Check out this company, this is where I bought all of my drives: http://www.kelinginc.net/NEMA34Motor.html The second and third steppers listed on that page are very reasonably priced and should be plenty powerful. I am told their steppers are excellent for the price point. You will of course have to adapt them to fit the mill.

If you get obsessed with incredible rapid feeds, and want a closed loop system, look at servos, but it will take a lot more money. Realsquash and I both just completed control retrofits on older CNCs. You can find both threads detailed in this section. His was a servo based machine and mine was stepper. It will give you some good ideas on getting it off the ground. In my case, it turned out to be a shit ton more work than I anticipated, but the machine stayed well inside my budget constraints. I think I have about $2k wrapped up in the whole deal, including the purchase price of the machine.

As for the Gorton forum, they will let about anyone in. It just takes a while for the mod to read the application and punch the button...

Jnutter on here has or at least had a Gorton too. He may know more about this particular machine. Are you going to run both heads on it? I would love to have a uni head for my old gorton, but you are probably way to far away to sell and ship me one :D

Later,
Jason

Thanks Jason,

I have followed both Yours and Realsquash's thread on your respective CNC mill threads on here for a while. Lots of good info.

The dimensions for your BP series 2 sound really close to the Gorton I am buying. So I figure 6K lbs would be pretty close. When you put your CNC BP series 2 in your shop did you have any problems with the floor especially when operating? I am a little worried that the floor where the Gorton will sit will be a little thin. One inch plate of steel may be in order...

The heads up for the stepper motors was most appreciated as I am probably going that way over servos as rapid traverse speeds aren't that important to me at this point. I am figuring that steppers would be a little more cost effective in terms of converting the machine to CNC and easier to hook up without having to worry about the closed loop portion of the wiring with servos.

I probably won't be running both heads. Tell you the truth I have no idea what I am going to do with the extra head but shipping would probably kill the deal.... but if you ever find yourself on the westcoast with LOTS of extra luggage capacity we may have to talk :D

Thanks again!

PS I also found a lot of Gorton Manual info on:

http://gorton-machine.org:8080/machines/index.html

for a lot of the machines Gorton made. Just to help for future reference.

[jnutter]

I have applied to the Gorotn Yahoo group and awaiting to hear if I am allowed to be part of the group (moderator controlled). Thanks for the heads up anyways!

Vinito is the owner of the group and I'm one of the moderators. We look at everyone who wants to join to keep the spammers out (seems to be working). This can cause a delay, sorry about that. Actual posts in the group aren't moderated.

I've got a Mastermil 1-22. It weighs roughly 3K lbs, compared to around 2.2K for the same size Bridgeport. Gorton built everything extra rigid, which translates into heavier walled castings. I don't know what yours weighs. Don't be shy about posting to the yahoo group and asking. I know there's some people on the group who own 2-30s.

For what it's worth - I'm mainly am mechanical engineer, but I also do some systems and controls work. I would suggest going with servos if you have a choice. I've found servos work out much better than a stepper with an encoder on the manufacturing equipment I deal with at work.

[Wicked_S10]

No, I have had no issues with the floor of my shop. It is only 3" thick concrete, w/ no mesh or rebar, but it is fiber reinforced. I probably have a combined weight of about 8 tons along the south wall of my shop, and the slab is showing now signs of stress cracks or sinking :)

As for the weight, The Gortons are normally quite a bit higher in weight than a similar sized b'port. This at least applies to their older machines. It is possible that in the later years they began to lighten casting to save money, but I doubt it. Point is, if it is the same size as my B'port S2, then it could be much, much heavier.

This is a good thing once you have it planted where it belongs, but it is a royal PITA until then :D

Later,
Jason

[Wicked_S10]

For what it's worth - I'm mainly am mechanical engineer, but I also do some systems and controls work. I would suggest going with servos if you have a choice. I've found servos work out much better than a stepper with an encoder on the manufacturing equipment I deal with at work.

I completely agree that a well designed servo system is superior, however it typically isn't that easy, especially for a first timer. If you are starting with some factory stuff, like realsquash, it makes life easier, but if you are trying to go the surplus route and matching servos and encoders and drives, it can rapidly get out of hand. Not every servo will work with every encoder and with every drive. Buying brand new servos, encoders, and drives, even decent imports, is about 3x the money of setting up steppers.

My B'port would miss steps now and again in the beginning. The solution was to slow it down a bit. Sure I can't hit 800IPM, but the machine has a resolution of .0001", and if I don't try to push the feeds to high it holds perfect tolerance.

Later,
Jason

[LCexplorer]

Thanks to Wicked_S10 and jnutter for helping me with figuring out the weight of the Gorton 2-30 trace mill I bought, I finally had it moved after some lengthy delays like trying to find a Hiab truck big enough to move it. The access was limited and the boom had to be in excess of 40' to reach the Gorton in order to move. After having the first Hiab driver drop off the face of the earth after making arrangements, I finally had to hire Phoenix Truck Crane in the Vancouver area and these guys were excellent and very reasonable ($130/hr as compared to $200/hr for the next closest guys). When moving any equipment always state weight and required boom length to reach the machine as that does save you having to pay for to small of truck from the dispatcher. The first truck they sent was a 30 ton Hiab crane which wouldn't even budge the Gorton, so they sent out a 60 ton Hiab crane the 2nd day. The 60 ton Hiab crane made it look easy with a very professional driver who knew what he was doing, Thanks Serg! (By the way ask for Serg if you need machines moved, he has doen a lot and almost saves the need for a rigger, PM if you want to get a hold of him directly). Anyways here's what happend in pics:

The 60 ton Hiab crane truck they sent with the shop they had to remove the Gorton from in the background (red eaves):

http://www.mybackyardjunk.com/Hiabtruck.jpg

and the 60 ton Hiab crane attached:

http://www.mybackyardjunk.com/60tonhiab.jpg

Getting ready to drag it to the door:

http://www.mybackyardjunk.com/Chainingup.jpg

Dragging it (you can see the spot it sat for years:

http://www.mybackyardjunk.com/Dragging.jpg

To the door:

http://www.mybackyardjunk.com/Setupdoor.jpg

Now out the door:

http://www.mybackyardjunk.com/Outthedoor.jpg

Now lifting time (the Gorton had to go over a couple of storage sheds in order to be put on the back of the truck):

http://www.mybackyardjunk.com/Upupandaway.jpg

http://www.mybackyardjunk.com/Highabove.jpg

http://www.mybackyardjunk.com/ontothedeck.jpg

All in all I can't really complain about the cost (almost $600) as they dropped the Gorton mill at my house which an hour away. I figured I would post the pics for those thinking of buying a mill of other heavy equipment and costs involved out side the purchase price.


Now onto to figuring out how to CNC this mill....

[Wicked_S10]

Did they tell you how much weight was on the end of the boom? A lot of those trucks have load cells. I am just currious how much it ended up weighing. The weight rating of the crane is deceptive, as it is based on picking up a load mostly vertical w/ a certain boom extention and other variables.

Glad to hear you got it home alright.

Later,
Jason

[randii]

I probably won't be running both heads. Tell you the truth I have no idea what I am going to do with the extra head but shipping would probably kill the deal.... but if you ever find yourself on the westcoast with LOTS of extra luggage capacity we may have to talk :D
If you guys can work out the details and can crate up the bits, I make a semi-annual pilgrimmage from Sacramento to Michigan as penance... I mean, to visit my inlaws. :p The wife goes every year, but this is the peace we have negotiated. :shrug: Anyhow, my folks live just outside of Midland, and I've got Subaru-space open for the trip.

Randii