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

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(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?

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