On Tue, 31 Aug 2010 08:07:03 -0500, Pete Keillor
wrote:

On Mon, 30 Aug 2010 21:28:29 -0500, Don Foreman
wrote:

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.

Could you anodize that o.k. with the steel blade in there? I assume
you'd need to guarantee the solution didn't get trapped in there.

Pete Keillor

Yes, you need to keep the solution out of the cavity and also need to
protect the external steel from the solution -- wax, tape, asphaltum,
nail polish, or what have you.