look for suggestions Plug welding with TIG

[heychris]

All,

Thanks for your suggestions on my frame stiffening of old car restoration post.

I am now plug welding some braces into the old unibody frame rail.

The new metal is 14 gauge hot rolled square tube that is inside the existing 16 gauge sheetmetal.

I drilled several 3/8" holes in the 16 gauge sheet metal..

I've done a couple of the plug welds and found that the best way is to start the arc on the 14 Gauge and slowly circle outward until the full weld is complete. I feed in quite a bit of filler in the process.

Are there any suggestions for effective plug welding? I have to do some of the welds on the bottom of the car. Does anyone have advice for welding upside down?

[shovelon]

Looks good, but for under the car use a mig.

[B_C]

yeah especially on "Hot Roll" stuff is junk to tig, also 3/8 holes aren't much to hold anything I don't know
how strong you need them to be?

[heychris]

They are frame rail supports, So I'd like them to be pretty strong. I know Hot rolled steel is supposed to be hard to tig, I've never seen much cold rolled square tubing available. It seems the most availablity in sizes and wall thickness comes in Hot Rolled. What is the problem with Tig welding hot rolled steel?

[Donoharm]

the problem is you have to clean it before welding

overhead/upside down tig is not the most difficult process , make sure you don't make a blob that will fall on your mask or if a blob may appear stay out of it's way