http://www.bing.com/images/search?q=J-B ... orm=R5FD12
I think maybe finding an aluminum bolt or possibly a piece(s) of rod close to fit, and then weld it up .
Fill the hole just under the surface and it should be a little easier.
It looks like the piece was lying down and the gas was blowing the puddle around.
( please don't take it the wrong way,no ill intent here) Just throwing the idea of filling the hole so as not to have the
argon (or what ever gas or combo) blowing back at the torch/puddle, this might let the gas purge the puddle instead
of blowing the puddle around. I think that's why you have all the inclusions.
The whole project is looking great! The added flow you pick up will surely help! The electric pump is pretty clever!
Hey, isn't this how USMC 500 got started ," I was only gonna change the air filter"
Tuck\o/