STOCK FLOOR BODYROP!

I know this might have come up heaps before but I am after some solid answers on what you guys have done...

Say if I was making a new clip from firewall back with 75 x 50 RHS (2.5"x2") what method is used to join the new rails back to the old rails at firewall and maintain full strength???

I have my own idea's and have shortened chassis' before but I am interested in what you guys have done to join the new rails...

i graphed my new frame into the old clip welded that then ground down the welds and plated around where the two met

I was thinking of drilling big holes in each piece near the join (fron section of chassis and new rails): sides, top and bottom then sliding strips of 5mm flat plate in there and plug welding the holes up so the plate is half in each piece when joined together...

this method is used when shortening chassis and you can bend the plates accordingly...
it's like an internal chassis wrap...

A mate also recomended diamond strapping where a diamond shape plate is welded over join overlapping each piece half half.


Anyone got any other ideas or photo's?

Edited: 12/2/2005 2:56:24 AM by tandem

I redid my frame from the rear of the cab back using 2"x4" tubing. I have a Mitsubishi and the tubing slid right into the cut of portion of the stock frame. I welded the seam and then used a piece of 3/16" plate to cover the seam on the inside and welded it to both sides to add strength. If the tubing you are using will slide right into the stock frame rails, I would suggest using the same method. You can cut out a diamond shape or any other shape for that matter out of 3/16" or 1/4" plate and weld that at the seam to add strength and keep the joint from flexing. Since your frame rails are probably larger than 2.5" (around 4" like mine perhaps?) then you might want to take a piece of the 2"x2.5" tubing and cut a triangular piece out that would taper the width of your frame down to the width of the tubing. This will reinforce the joint further and will also make the change in width look less dramatic. There are probably and infinite # of ways to do this. This is just one idea.

Originally posted by SHORT n SWEET



I was thinking of drilling big holes in each piece near the join (fron section of chassis and new rails): sides, top and bottom then sliding strips of 5mm flat plate in there and plug welding the holes up so the plate is half in each piece when joined together...

this method is used when shortening chassis and you can bend the plates accordingly...it's like an internal chassis wrap...

A mate also recomended diamond strapping where a diamond shape plate is welded over join overlapping each piece half half.

Anyone got any other ideas or photo's?



thats a good way to do it. I always try to plug weld stuff for extra strength.

yup i would plug weldit and plate the outside were it joins atleast 6 inches...

If you have a box frame, you don't necessarily have to use any of those methods. They can't hurt though. You can just butt-weld them together if they are boxed. Just make sure you v-grind the adjoing pieces. on a toyota there is a spot on the frame where the box tubing is almost exactly 2x3" which is a common frame choice. If you cut it in the right spot you can metal-finish them together and have a much cleaner end result. But Aaron (HIonPsI) is also right. you can plate around it as well to shape the frame to the right size or pretty much any thing if you got the tooling to bend thick plate. But again, just make sure you v-grind the adjoing pieces.

maybe its just me..but i wouldnt feel safe with my frame butt welded together in the front and ground down smooth......

tell that to Bob Grant. do the plug weld then

Check it