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ericfragola
11-29-2011, 05:45 PM
Just curious what.everyone's opinion is on stitch welding. My friend did it on his s14, and it really tightened up the body roll. I'm planning on using the car for auto x. I currently have a full rollcage and TRD suspension so my body is pretty tight already. Also, my interiors fully out right now since I just welded in the cage. What're all the pros and cons?:)

Car_Barn_Bandit
11-29-2011, 09:13 PM
Seam/stich welding is a great way to stiffen up and resist torsional forces on your chassis. Basically, our cars are held together with a lot of spot welding done by machines. These welds do not create the strongest connection and each sheet of metal has more give. Going back over the seams with welding makes for a stiffer and stronger connection. I don't see any drawbacks unless you burn through metal, expose metal to become rusted or set your car on fire.

I imagine it's something that most car manufacturers would do if it wasn't cost and time prohibitive. As long as your car is rust free, it shouldn't be too bad. You might encounter some issues with the sound deadening material they use on the rear seat pan. I believe it covers a few seams.

Otherwise, I recommend a TIG welding rig if you're doing it and are new to welding. 70-80 amps should be enough on the sheet metal. I'd be cautious about going over 90 on an older car. Get a good wire wheel and strip the paint near the seams. Then clean the welds when finished and prime them. Take photos if you do it, it'd make a nice write up on here.

Conrad_Turbo
11-29-2011, 09:41 PM
Pro: stiffer chassis and this allows for easier suspension tuning as you don't have to tune around a flexible chassis.
Con: lots of work

I would recommend using a MIG welding process with gas, not fluxcore. Don't TIG...TIG needs clean metal and you will just end up with weaker welds if you get any sort of porosity due to the weld area not being spotless. Use dry ice to break out all the sound dampening and an adjustable air chisel to get the seam sealer removed. Everything after welding should be recoated with paint on the inside and rockerguard/undercoat on the underside. This will prevent corrosion.

Alternate front to back and left side to right side of the car, and most of all...make sure the car is straight before you do this. Because it'll stay that way until the day it is crushed for scrap metal.

Hipster Lawrence
11-30-2011, 02:22 AM
Do you add more spot type welds or do you actually run beads down the entire seam?

KoreanJoey
11-30-2011, 02:54 AM
Not the entire seam but lengths at a time instead of just spots. Welding the entire length will probably create distortions from the heat.

ericfragola
12-02-2011, 12:22 AM
Awesome feed back! I'll definitely be posting some pics for everyone to see. :) planning on doing it after my new turbo comes in. Just ordered a nice gt35. Can't wait. Should be any day now. I want to see what the car feels like before and after since I haven't driven the car in 8 months since the build. I did drive it the other day but the Turbo seals were blown so I only drove it around the block before parking it back in the driveway. Smoked out the entire neighborhood :o

Hipster Lawrence
12-04-2011, 03:03 PM
Not the entire seam but lengths at a time instead of just spots. Welding the entire length will probably create distortions from the heat.



I was considering doing this to an mk1 in the future but the gobs and gobs of seam sealer made me think twice?

KoreanJoey
12-04-2011, 10:10 PM
It isn't fun. That's for sure. BUT, for someone wanting to keep the functionality of a car without a roll cage, stitch welding is a good way to add stiffness.