25+ years ago I was competent (though no expert) in arc and gas welding in
High School. When I got my Tiger I purchased a Lincoln MIG PAK 100 (88 amp
rating) to replace rusted panels. At times I can get a really good bead
going for a few inches then !@#$%^&*. I most often am blowing holes in the
22-24 guage metal used in the Tiger's wheel wells (and elsewhere). I have
had no problems with the thicker metal such as the inner rocker panels. All
my welds have been lap welds and I have tried to keep the puddle closest to
where the metals lap (thus double thickness).
Here are the perticulars: I am using the lowest "A" setting, Argon 75%-Co2
25% gas (more on the gas pressure later) and have adjusted the wire feed
both above and below the recommended setting. I try to keep the weld going
at an appropriate rate, but it seems like the slightest bobble, or change in
the metal and ZAP!..., a hole in the metal. Then attempts to "fill" it in
create blobs, unsightly welds and often just extends and enlages the hole.
Thus, I attempt to grind most of the weld down and go over it again. This
only perpetuates the problem as the surface is more irregular than before
and it goes on and on (I'm stubborn). In the end I have a weld I have gone
over 5-6 times, is a 1/2" wide, and even with extensive grinding still looks
rather crappy. Today I welded about a foot and a half (yea,that's 18 inches)
and it took about 8 hr's (weld/grind etc.) to get it looking as bad as it
does. It really kills me because at times I'll get say 3 inches (in a single
pass) that look great. I clean all the metal, the wire is not jamming and
the gas is on. Any tips??? I have tried copper behind the weld (in the few
cases where I can actually reach to get it there).
This brings me to the gas. I have used Argon/Co2 feeling I can use all the
help I can get. A professional welder friend (he welds Aircraft Maintenence
for Fed-Ex) says 4-6 pounds is all I need. The guy at the gas store says
15-20 pounds (but then he's selling the gas). I have been going with about
10 pounds, but am really eating the gas. What with all the weld/grinding
etc. I'm getting maybe 3 linear feet of crappy finished product out of a 20
pound bottle. Since I have had this welder I have used 5 pounds of wire and
60 pounds of gas. Here in Calif it's just about $22 a bottle with all the
haz-mat stuff etc.
Should I forgo the Argon (and its cost)? How much pressure should I use?
Finally, I often find it difficult to see with the mask on. I have gone from
a # -10 to a # -9 lens. Would I damage my eyes to go to an # - 8?
Thanks for any help that might come. But please, spare yourself with long
talks about metalurgy and the like. I am after setting and technique
information. Thanks, Tom Witt B9470101
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