Chassis Jig

[53Vipette]

I've been dragging my feet to build this jig for a while. My project is getting to the point where I had to have it to make any measurable progress, so I grabbed my debit card and rolled over to the metal supply yard. I went with four pieces of 4"x4"x20' .120 wall tubing and two sheets of 4'x8' 3/8" and a handful of scrap I had laying around the shop.

To start, I cut the main rails to 15' and then cut 2 piece more pieces of tube to 4' long. Overall, it'll be 56" wide. The metal yard pre-cut my 3/8" into two 6' x 2'. I chose to build in a vertical position because it was easier to find a 4" wide swath of shop floor that was almost lump free then something 4'x15' wide and smooth. The pics and time lapse don't show all the clamps and bracing I used to make everything square. It ended up being 1/16" out of square, I blame that on mismatched lengths of tube.

I hope you guys find this of use and I'll answer any questions you have.

Thanks for reading!


I recommend watching the time lapse of it so you can get a grasp of all the subtle nuances... However, as of right now it's still uploading at mid night on 1/24/2013 it should be done in about in a few hours.





I had planned on TIG welding everything but was foiled by an almost empty bottle of Argon. Luckily, my handy Miller Matic 140 MIG was ready to go.



I added these diagonal braces to keep it square and they will also support two similar pieces that run parallel to the main rails. Fast forward after two days of fabrication and you get this...





I staggered the legs in an effort to balance any torsional loads. Added benefits are extra storage for tubing. The spread on the legs is roughly 5 1/2" so you can stack a fair amount of stuff.





The piece of tubing that is under the 3/8" plate are guides to help the plate slide parallel to the main rails. The concept is to have the two main "pads" be movable for different length wheel bases. Once the pads are set I'll square and tack them in place. A third will be used for the motor and trans to sit on.