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Discussion Starter · #1 ·
I am having a lot of trouble welding on my stang. The skin is too thin. My big arc welder cuts through the metal instantly, even on the lowest setting. Gas warps the metal, even trying not to get it too hot. I got a small flux welder, it cuts through almost as fast as my big one. I finally welded some by doing tiny spots. If you only touch the steel for a split second it will tack. Does anyone know how to not burn holes completely through the car. I like to cut out rust and weld in new metal, but if this keeps up might have to use bondo (heaven forbid).

2 67 stang coups - 1 67 cougar - 1 75 mgb

Discussion Starter · #2 ·
Welding with an arc welder I wouldn't want to try. I've read on the forum you can get special tiny rods to do this. Also on this url:
There are a couple products, stitch welder and spot welder from Eastwood company. I haven't used them but they must work.

With the torch you'll need a really small tip to generate less heat. This also takes some skill.

A mig is the best way to weld thin sheatmetal. If you have a lot to do I would highly recommend getting one. You can always sell it when your done and get probably 75% of your money back. I had no experience welding and I did OK with a mig.


65 GT Coupe all dismantled waiting for resto.
67 Restomod Coupe all sheet metal done, next is assy.
69 Mach 1, SWMBO say don't you dare take it apart!
91 5.0 LX HB, daily driver.

Discussion Starter · #3 ·
MIG is defanately the way to go with sheet metal. I'm using a .023 or .024 (I forget which) with gas, and it works real good until you get to some of the really thing spots. Sams has a Lincoln sp100 for a couple hundred bucks, but it's really not big enough.

'67 Coupe project car (Did I say project car? I meant pile of rust)

Discussion Starter · #4 ·
I agree with the Mig, I use .30 guage wire with panther gas and have welded my engine compartment as well as my floors. It is a nice clean weld and with little practise will come easy, I never welded until two months ago. My Mustang neighbor shared his welder with me as well as his knowledge and things have gone well.

Discussion Starter · #5 ·
The other guys are right. Use a very small tip torch, or small - .023" wire MIG. Don't use the flux core wire, if you can help it. The Eastwood "tools" are not the way to go. I had both and you get what you pay for. One good Eastwood product is the copper welding back up plate. This helps to prevent the burn through on the thin areas. Also, it is important to do only very small sections at a time, and make sure the metal is CLEAN. Practice on same gauge scrap first. Good luck.

10,588 Posts
Hi Walt,

I kinda do this stuff for a living so bear with me *G*

1. Metal prep is paramount...impurities promote bubbles which can blow through thin material....get it clean!

2. Practice! Develop you settings and technique on scrap material of the same type and thickness...

3. Fit! If you follow the legion of butt welders here, make sure that fit is TIGHT......Personally, I'm a flanger and lapper but a lot of guys here feel that promotes future rust...

4. Technique! I prefer to use straight Argon, .025 wire and the stitch welding panel on my Lincoln SP200 AB with the arc volts in the 12-14 range and the wire feed at around 100ipm....the timer is set at 1.5 seconds on/ 1 second off...
Remember, a big machine like mine just gives you more flexibility but doesn't mean you can only weld thick can simulate this on your welder by manipulating the trigger...just watch for the puddle to solidify and put your next one down at the leading edge of the previous one...the trick is to start the weld on the area where the gap is straddled...I sometimes use a forehand technique as opposed to trailing to just spill the puddle over to the gap area...
When metal gets down in the 18-20ga range, I switch to the TIG welder for more control.

5. Backup! On thin material, it's often helpful to use a copper or brass backup....after tacking in the patch, the backup can either be clamped, supported or riveted in place....I've even used copper water tubing smashed flat in a pinch.....the trick is to make sure it contacts the back of the weldment to prevent burn-through....the copper carries away the heat rapidly and supports the back side of the weld...

6. Take your time! With many welds, you only have one chance to do it right and the actual welding time is, prepare, practice and think everything out ahead of time...then go to it!

Good luck!


Discussion Starter · #7 ·
Thanks all of you for replying. You were all a good help. The suggestion about the backing plate worked like a charm. I even tried it on my MGB. Gunna save me a lot of problems.
Pat you were right, I had some 2" copper pipe. A vice did a great job of making it flat, a 4lb hammer did the rest.

Thank again ya-all

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