[Big Rig]

Hey guys, I am pretty new around here, been lurking for a while, but this is my first post.

I am big into lowered vechiles, not static drops but adjustable suspension (bags or hydraulics). I was wondering is anyone has built thier own frame in their garage and for what kinda car. I primarily do trucks and have altered frames in the past, but the project coming up (hopefully able to call it the shop truck in the near future) is far to radical to use any of the stock frame except the front suspension.

I am thinking of building a jig/ welding table, 4' by8' or 4' by 10' do jig frames up on with out riggers for the front suspension. hanging the rear is no big deal but I'm worried avout the front end.

any suggestions? how do you do it? any homemade jigs? pictures? any help would be greatly appreciated.

and for reference, the project is a 1986 chevy 1/2 ton short box.
plans include-shaveing everything, chopping teh rockers so it lays door, chopping roof, suicide doors, tilt or dancing box, and maybe a small sectioning session.

Thanks in advance for any input you guys have

Big Rig

 

[BillyShope]

Unless you're also going to weld up a frame for your brother-in-law and the guy down the street, I wouldn't think a jig would be necessary. Just make sure the suspension pieces are straight with the world and that you can pick up the body mounting points, which means frequent checks as you weld. I welded up a tubular "space" frame for a sprint car without any fixturing. Required a little "encouragement" with a come-along when it came time to weld the sides together, but it wasn't too bad.

 

[cboy]

Here's how a guy did a simple T-Bucket frame/chassis.

http://www.nationaltbucketalliance.com/tech_info/chassis/Rchassis/index.asp

 

[astroracer]

Check out my Journal... Three or four pages into it there are complete plans for a couple of jig tables I built this spring.
Mark

 

[americanLT1]

Big Red, This scratch built frame stuff is new to me too, but I've started mine without a jig and so far with good results. I don't know if I can explain this witout pics but here goes. First I made a four leg stand out of old 2" square tube, then I attached it to the bottom of The mustang II cross member I'm using. Each leg has a leveling screw so you can adjust side to side front to back and ride height. The guy with the T bucket was able to lay his flat, but mine has compound angles, 20 degrees out and 20 degrees down, so I laid mine out on the floor using the leveled cross member as a reference point. I'm using 2x4x.125 wall rectangular tubing. The fellow with the T bucket was using a miter saw to cut his angles. I'd like to know how well that worked, because I bought the best chop saw Dewalt makes and it does a great job with straight cuts and single angles but not with compound angles. I used a milling machine to finish my angles for a near perfect fit, but that's probably not the only way. After all the pieces were cut I drilled two 3/8" holes 1" apart on the top and bottom of each tube about 1/2" in from the end. Then, I made inserts to go inside each tube with the same 20 degree angles. I made these from 3/16 thick steel. I slipped the inserts into the tubes and marked the fist hole with a pencil and drilled and tapped for 1/4" bolts. This way the bolts hold the inserts and the tubes in place so you can check and adjust your level and geometry before you tack weld. First I tacked the two pieces of tube to the cross member, made sure they were level and square to the cross member and each other, then I tacked all four corners of each tube, added two pieces off 2" square tube across each frame rail to hold them parallel with each other and at 90 degrees, then checked level again with reference to the cross member to be sure nothing moved. After that I welded the inserts to the rails through to 3/8 holes without the 1/4 bolts, then removed the bolts and welded them. Now the inserts were securely attached to the rails. Then I finish welded around each joint, pausing to keep heat and warpage to a minimum. After it cooled I laid the welded assembly in place on the floor, leveled the cross member and shimmed the rear rails to ride height, and was pleased to see the largest error I had anywhere was 1/10 0f a degree. By the way I used a digital level with 1/10 of a degree resolution, and I'm welding with a 225 amp mig welder. I still have to build the rear portion of the frame with a triangular four link but expect the same results. There are probably easier ways to accomplish the same results but this is a first for me and I think the results are good. Anyone with comments good or bad related to my methods are encouraged to respond. I'm certainly no expert, some of you people are way smarter than me and I've learned a learned a lot from you. Good luck Big Rig...Ed