.023 or .030 mig wire for 20-22 gauge auto panels on 30's cars?

[BOWTIEGUY]

Looking for some recommendations for welding patch panels in older classic cars. The 1930's seem to have used a lot of 19 gauge in their body panels. I'm repairing them with 20-22 gauge material.

I have an older Miller 180 mig that works great..just wondering if anyone out there can recommend a good wire diameter (.023 or .030) for what I'm doing. Need to step down from my big spool of .035.

BTW: Miller recommends ER70S-6 over ER70S-3 wire for dirty/rusty metal, what do you think?

Thanks as usual!

[H80N]

Mig wire tends to be very tough to grind and to work... mig seams tend to crack when the sheetmetal is worked and planished..... and as far as grinding... even the easy-grind vatieties are not very good..........
TIG is much preferred if you have access to it...
if it is a valuable car... those seams need to be pretty on BOTH sides....
I do lots of automotive sheetmetal so may have been prejudiced by having to redo..many nasty migged in patches..
just my 2c worth

BTW.... that metal needs to be clean..."dirty rusty metal" has no place in a restoration...

[duaneb55]

Either would do but I'd go with .023 and the recommended -6 in my opinion. The .023 won't require as much heat as the .030 and will be a little easier to control. Again, IMO but I've never restored a 30's gem.

[bridgeportBJ]

.023 or .030

I weld alot of patch panels and I found Esab .023 to work the best by far.
BJ

[BOWTIEGUY]

BTW.... that metal needs to be clean..."dirty rusty metal" has no place in a restoration...

10-4 on that ...but on some occasions you don't have full access to the inside panel surface...

Thanks..

[BOWTIEGUY]

I weld alot of patch panels and I found Esab .023 to work the best by far.
BJ

Thanks...that's what I was hoping to hear.

Happy New Year Guy's!

[H80N]

If you MUST mig it, a soft 023 wire like the old Lincoln Easygrind would work...
but the very best bet is TIG welding butt jointed patches and planishing...

or if you have the skill and patience... oxy fuel butt welds... hammerwelded and planished.....

an awful lot of valuable tin has been ruined by the lap, mig and bondo... crowd..

MIG would be my third choice.. Butted not lapped...

[hisey606]

I've used Hobarts wire .023 for years on alot of bodywork on 40's trucks up through mid 80's trucks and it works very well. If possible on panels that you can't access the backside to rustproof, use a body panel epoxy. I attended a 8 hr training class on this stuff and its really awesome! Sheet metal will rip before joint fails and its totaly impervious to moisture. Thats what I do....

[Keith_J]

Another vote for GTAW. I spent a good part of the summer doing just that, most of the time was fitting and cleaning the rust off the back sides. There were places I couldn't get the rust out and I paid for that in pops which trashed the nozzle and tungsten.

I used 0.023" S-6 for filler and in GTAW, it grinds easily. Just watch heat on grinding as that too can cause warping. Yes, S6 has more deoxidizers than S3 so it quiets the weld pool. Oxygen from rust combines with carbon in the steel, making the weld pool fizz, deoxidizers like silicon and aluminum grab the oxygen before it can react with the carbon and form slag, this you can see on the finished weld as a blob of glassy material.

I think GMAW (MIG) takes on carbon from the shielding gas which makes grinding harder.

[shovelon]

Another vote for .023 easygrind wire in your mig. But be aware that the .023 is really soft.

I have some of the old Linde .023, and the new stiffer Esab .030.

I use both in my Linclone mig, and the .030 in my cold wire feeder for tig work.

You can planish it pretty good, or just grind it off.
And yes it is easy to grind if you use Argon75/25Co2.

[BREED]

I have a 1972 Nova that needs alot of welding. So, I wont be able to use my Millermatic 212 ? The smallest wire is .030

[walker]

It would surprise the heck out of me if you couldn't run .023 in a MM212. I can run it in a 252 an old MM200, MM185, MM140, MM135, LN-25, ...

I have also done a fair amount of work on hot rods. I have tried a lot of different processes and have come to the conclusion that they are all valuable in one way that the other is not. I have used O/A and hammer welded, but it inputs a lot of heat, the weld does not seem fragile though. I have tigged, again welds are more ductile, but a slower process. I have also migged them. The MIG and grind repairs seemed to crack easily when the area was worked after the fact. The best mig repair is a butt weld. I have found that if you fit the piece and tack it in, then go back and spot weld (good hot full penetration spot welds) evry 2-3 inches. then start making 1" welds around the perimeter. After you make the weld, set the gun down and pick up a hammer and dolly and hammer the weld (doesn't need to be dead flat but at least take the majority of the peak down). This has proven to keep shrinkage to a minimum. Then, and here is a good trick, grind the weld down with a stone, NOT a flap wheel. When you grind it you DO NOT want to touch the surrounding metal, just knock the weld down to the level of the metal around it. The problem with using sanding disks is that most people tend to sand the weld flush with the metal around it, but also sand some of the adjoing metal, making it much thinner. Don't do that!
Also I have had better luck with .023 and CO2, than 75/25. I know it seams counter intuitive, but that has been my experience. It seems to allow the small welds to penetrate further without inputting more amps from the machine, YMMV.

[walker]

Link to the 212 capacity sheet. .023 is in the range of this machine, I am not sure where you are getting other information, except for the replaement liner, which are usually said to be for .030-.045 wire. You can BTW run .023 in them with ZERO negative effect.

http://www.millerwelds.com/products/mig/product.php?model=M00456

[BOWTIEGUY]

I have a 1972 Nova that needs alot of welding. So, I wont be able to use my Millermatic 212 ? The smallest wire is .030

If you go to Millers Calculator page:

http://www.millerwelds.com/resources/calculators/

They show .030 for 22 gauge...I have been using .035 on my panels...but it's a bit of work trying not to burn through..but I have been doing it directing the heat towards the new steel and letting it flow over.

This forum convinced me that by going to .023 I'll have better heat control over
.030/.035.