stitch welding preparation

I am planning to stitch weld my cars unibody for increased stiffness. i know i need to strip the car and remove seam sealer, paint and clean etc. I have read that the chassis must be square and level while stitch welding. What actually does a square chassis mean and how do you make sure that it is square and level? thanks

What you want to achieve is a stress-free position foe the car. If it were to sit on a non-level floor on jacks that were set to the same height, the car would want to twist.

So, you need the tops of your jacks to all be the same height. Use a laser level and pieces of plywood to do this.

Also, support the car by the suspension points. You want to copy the load paths into the tub as if it were sitting on the suspension.

As with all automotive welding, move around, dont do all the welding on one shocck tower and then the other one. Shrinking weld bead has a way of distorign things.

I put stich welding up there with drilling bolts to lose weight. Kinda at the point of diminishng returns and not anything I would do unless I was serious about some form of competition.

It's effective. Lots of work, but if you want an inexpensive way to increase chassis stiffness and you have time but not money, it's a good option.

To clarify NOHOME's post just a bit, support the car where the springs touch the chassis.

thanks for the reply guys.. So if I need to support the car from where the springs touch the chassis, is it ok if I just leave the suspension and tires on the car while i am welding the interior ( wheel wells, rear struts etc.) on level ground and then strip it completely to progress to the engine bay? Also I would like to hear any other tips before actually performing the task as it is quite possible to ruin the car.. cheers..

If all your tires are the same size and pressure, the floor is level, and the chassis matches the floor, I don't think you will have any problems. I would just worry about a spring that has given up and the car is hiding its symptoms with the help of a sway bar.

If it were me I would try to eliminate all the variables I could, kind of hard to undo what you are going to do

please, take pictures. ive always wanted to do this to a unibody muscle car, and it would also be benificial to you for feedback from those who have done it before.

good point jgrewe. thank you. I always take photos of my work Dusterbd13 and I would happily post it here but I am not in a hurry to do this job. I prefer gathering as much info as possible first. I can give you a couple of links I found very useful though. take a look..

https://www.youtube.com/watch?v=EY0wEKg3dAI

http://www.cgbagne.com/theturtlebuild/?tag=stitch-welding

Also, I would like to hear more from you people . Thank you..

tosdiri wrote: I can give you a couple of links I found very useful though. take a look.. https://www.youtube.com/watch?v=EY0wEKg3dAI

"Broke Racers" huh? Watch out GRM!