Replacing typical rust areas on the 1930 Model A truck
 

Hi,
Starting to evaluate the typical rusted out areas of my 30 model A truck.
Putting a list together for replacement panels my question is what would be the best welder for application MIG or TIG.
Any suggestions?

Re: Replacing typical rust areas on the 1930 Model A truck
 

I have both but use TIG. but what ever type of welder you are using, you need to know how to weld in panels and not cause a lot of additional problems.

Chris W.

Re: Replacing typical rust areas on the 1930 Model A truck
 

I spot weld the panel in with MIG then finish weld with TIG. If you want to use a MIG, spot weld the panel in, then spot between the spots bouncing from end to end and you could stop and cool with an air gun. Keep adding spots between the existing spots until the weld is complete. The point is to not build any more heat than necessary in any one place. That is why you only spot weld then move to another area to do the next spot and so on. Then when you grind down the spots just respite any places that you may have missed.

Re: Replacing typical rust areas on the 1930 Model A truck
 

Same as #3
I might add do no replace more metal than necessary
Cut out rust to solid metal then trim patch to fit; not cut out to fit panel. Keep as much Henry metal as possible

Re: Replacing typical rust areas on the 1930 Model A truck
 

Thanks for the suggestions,l have welded back in the day
Just not thin body panels. Will most likely invest in mig welder,l read that the Hobart is a good unit and priced nice.
And l read that it is designed after the more expensive Miller units.
I have used Lincoln back in the day also a good welder.
I like the suggestion of minimal metal replacement always a good thing.

Re: Replacing typical rust areas on the 1930 Model A truck
 

I’m Miller all the way
I have a multi-voltage mig but never have much luck at 110v; use 220

Re: Replacing typical rust areas on the 1930 Model A truck
 

I have had a Miller 110V MIG for decades, works great on panels. I often wish I had a TIG much easier to control the heat, so I am told.

If I were starting over and knowing what I know today, I would buy a TIG. Just my 2¢

Re: Replacing typical rust areas on the 1930 Model A truck
 

FWIW, I have a miller 251 that i have had for many years and 2 years ago, I went to a guys place and took a crash course on making and installing body panels. He dais that a MIG was OK but I might consider a TIG. I bought a TIG and after getting used to it, I REALLY like it and use it for more than just body work. I'm not a TIG master by an stretch but rather enjoy it (when the welding can be done in a comfortable position).

Re: Replacing typical rust areas on the 1930 Model A truck
 

Yes,Miller is a nice welder my budget says not right now my local welding supply guy said like l mention the Hobart is close to the Miller on a tight budget.
Has any one used those Cleco fasteners they look like they hold the panels nice when spot welding.

Re: Replacing typical rust areas on the 1930 Model A truck
 

Clecos yes all the time
I often use a panel flanger to overlay but butt weld where I can

Re: Replacing typical rust areas on the 1930 Model A truck
 

What here saying is more heat causes ripples in the panels your welding ,the metal is not that thick 16 thousands.

Re: Replacing typical rust areas on the 1930 Model A truck
 

20 gauge is .035 but yes still thin
MiG and tig both work well on 20 gauge
MiG is just more brittle ; tig more controllable

Re: Replacing typical rust areas on the 1930 Model A truck
 

When you apply heat to the panel, the following cooling shrinks the local area. uneven heating and its following cooling are what cause panel distortion. when you weld if you add too much heat the surrounding metal is sucked into the weld pool, this is undercut. on thick plates it's very easy to see this effect. on thin sheet, you basically burn right through. Tig welds are softer, more easily hammered on. You typically hammer a weld back to flat to get the metal to its original thickness and undo the warpage. This takes much practice. Mig welds are much more brittle. hammering the panel can crack along a mig bead. Tig will give a much better finished product, much much slower up front but less finish work. Mig is less work up front but grinding is harder and if you plan to hammer and dolly the panel to straight much more difficult. If you are okay using a little more bondo then mig is the way to go. Tig is much harder to master. I suggest doing a lot of practice on thin steel before ever touching the car with a tig..or mig for that matter...Ask me how I know.

Tig also has to be stupidly clean to weld. if you hit a pocket of rust or cut corners you will burn through the panel.

Re: Replacing typical rust areas on the 1930 Model A truck
 

I am capable of welding it with any systems there are and having taught welding many years ago, and you being on a budget, I would recommend you use an acetylene or hydrogen torch. Yes, it is old school and I recommend you do some research and practice on some junk panels before you attempt it on your project. This type of welding is called "hammer welding" as it involves hammering the weld immediately after while it is still hot. In all the people I taught it to, almost all could pick it up and make acceptable welds after an hour practice. There are videos on Youtube showing the basic method.
The nice thing about this system is, it is much easier to get a finished panel that requires NO bondo than with TIG. MIG is almost impossible to do this.

Re: Replacing typical rust areas on the 1930 Model A truck
 

Whichever method you decide to use, be sure to use the right size filler material, it will reduce burn through and other issues that might arise. I like 0.024-inch wire for MIG and 1/16-inch rod and tungsten for TIG. If you're still having problems with burn through, grab a piece of flat copper and use it to back the weld seam. Works great when filling holes as well. Tack the panel in and then alternate the location of each weld and keep them less than an inch in length, should keep the heat down to a minimum if you're moving and not sitting in one place too much. Good luck!

Re: Replacing typical rust areas on the 1930 Model A truck
 

Thanks for all the recommendations.