On Mon, 30 Aug 2010 15:53:04 -0500, Ignoramus24925
wrote:

I have two long aluminum bars 1/4 by 1 1/4, connected together in a
parallel configuration:

[==============]
[==============]

(they form a knife handle that holds the tang of a knife, sandwiched
between them).

I need to weld them together with TIG and my question is how. Again,
6061, they are 1/4" thick. What filler is best to use and what
amperage. Should I use lanthanated?

i

I'd say somewhere between 150 and 200 amps, but watching the puddle
will quickly tell you when you have it right.

Thoroughly scour the work with a stainless brush thoroughly before
welding. If it was done 15 minutes ago, do it again.

I would prefer a zirconiated tungsten to lanthanated, but La will
probably work OK too. I would avoid pure tungsten and definitely
avoid thoriated. I haven't tried ceriated.

For filler, I'd probably cut a strip of 6061 sheetmetal, or use 4043
or 5356. On thin material I'd use 4043 because it melts more readily,
but on your job 5356 would not be a problem and it would probably
provide a better color match with 6061.

Since it's a knife handle, I would anodize it when it's finished to
avoid the problem of black hands from aluminum oxide in the kitchen.
5356 will give a better color match when anodizing.