On Tue, 31 Aug 2010 09:13:19 -0700 (PDT), "
wrote:

On Aug 30, 10:28*pm, Don Foreman
wrote:

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

Ernie recommends one amp per .001 inch of thickness and then some
variation depending on configuration. So if you think of this as kind
of a butt weld that has been oriented strangely.........well that
would be about 250 amps.

That's a good rule of thumb, but it really addresses butt welds or
filet welds where nearly complete penetration is sought. That's far
more than would be necessary here. I've done welds similar to this,
didn't need anywhere near 250 amps. A puddle maybe 3/16" dia is way
plenty here and it's a lot easier to control.