What's the best way to weld in a drilled hole.

Hi Jody, man great job on the site and everything. My question is how to best focous the arc at the bottom of a drilled hole in aluminum? The idea is to build it up to re-tap threads in it for a bolt. I was using a 2%thoriated tungsten on pulse I can't remember what freq now, but it was very hard to get a puddle at the bottom of the hole.

Regards Dave Reid.

--------------------------------------------------

Dave,
a 2oo F preheat and a helium mix of up to 80 percent helium helps more than any setting.

i know what you are talking about. I once watched someone trying to get filler wire down in the bottom of a threaded hole with a skinny long tig cup.

he could fit the wire in, so he would puddle, stop, drop in bits of snipped wire, puddle again, and so on.

it was a slow go.