tig welding tip

[grumpyvette]

one of my friends was recently working on an older corvette with a rather large, thin,flimsy and complicated aluminum bracket that held the air conditioner compressor and serpentine belt tension-er, to the block and used its multi bolt, secured base for its strength, during the removal he forgot one bolt and tugged hard on the bracket and twisted it enough that it broke, or the previous owner had used air tools and overtightened it,in any case it was busted when removed, pricing a new one at salvage corvette yards showed that it cost several hundred dollars to replace.

SO, I got out my TIG welder, figuring even if I totally destroyed the bracket during the repair process he would be no worse off.

now Ive learned years ago to do some test welds on some similar size scrap aluminum and to use the minimum amps required so as not to warp the component.

he was surprised when I grabbed some scrap aluminum to do some test welds on and when I took the effort to re-grind the tungsten torch electrode, but once I worked the amps up to about 83 amps Id found the required heat, and gas flow rates and while the bracket was obviously not new , under a close visual inspection,its now very serviceable and it takes a close look to see it was welded.something I doubt would be true if I,d been testing the amp range on the weld while adjusting the welder

[tonycharger72]

How did you select you filler rod?

[johnc]

When you don't know the base alloy 5356 filler is the safest to try, just watch for cracking. The most common alloys are the 5xxx and 6xxx in wrought and 5xx and 6xx in cast.