pictures of TIG aluminum head need HELP!!

[jakeru]

There are probably more than one ways you can get this to work. Your current setup might work with a gas flow adjustment. What gas flow rate did you use, and how did you determine that number to be appropriate? (IE: did do any testing?)

If you can't make the current cup you have work by gas flow adjustments, even a modest increase in cup diameter could make a world of difference in improving gas coverage at high tungsten stick-out. Like stepping from you #7 up to a #8. (which are available for your collet body by the way, I've got one, I think its made by CK.) Or up to a #10. The smaller pyrex glass cup is "supposedly" a #8 size, but when I tested one out I compared it to a #8 alumina cup I have, and found the pyrex was bigger. I don't think the huge champagne nozzle (1"+ cup diameter style) would be the right tool for this job, because it might get in the way of your vision and filler rod access into the hole. It will also need a huge step up in gas flow. But then again if you set it up with the proper gas flow it could probably be made to work. You can also put a bend in your filler rod to reach around an obstruction.

Yet another idea is if you had a dual flowmeter (or extra gas bottle and extra single flowmeter), you could get another argon hose to administer a second "purge" flow of inert gas at the bottom of the hole. That would definitely help a huge amount for keeping hot meta down there happy while welding. You could set it up by drilling a hole in the backing plug you made, and then threading, pressing, or welding a small pipe nipple onto it, and installing the secondary "purge" gas hose onto the nipple. And letting the purge gas flow a little bit before and during welding.

I would probably just start by testing adjustments to my shielding gas flow however, it if were me and I hadn't done it already. Hold a real tight arc when welding on this thick stuff to concentrate the heat near the tungsten and to make a puddle.

You can always grind away the oxide layer, and excess weld deposit, and try welding again on your scrap head.

[performance]

Skimming real quick...Too much helium in the mix. You need a lot less and things will be better. Think about it: Helium is lighter than air, and it won't stay in place long, especially on those heavy, hot welds.
Argon sinks.

WAAAY too much stick out for that size cup.