I was hoping that a few of the better guys would chime in here.... I'm certainly no expert!

Some very good info right here.....

Hi Guy's looking for some help. I haven't picked up a tig in years and haven't welded much stainless. Below are a couple of pictures. I have tried a few settings an I ended up at 30 amp and no filler rod, at that setting I don't have any real undercut, but I'm concerned about the lack of penetration. Any help would be appreciated.

Thanks
Greg

Attachment 38613

Attachment 38614

Give us some more information --- like the gauge of the metal...

Greg, It's about 13 gauge. Also I'm using a 1.6 mm tungsten and a gas lense.

Greg

13 gauge tube is about .095" which is 1/16th of an inch we'll call it....


Miller weld calc calls for 50 to 80 amps for TIG on Stainless butt weld.... using a 1.6mm tungsten and same size filler... Gas flow should be about 11 CFH


So you're close.... Personally I like to choose a bit on the high side of the range -- because I can back off the amperage with the foot pedal -- or hand control and just use whatever it takes to get the job done.

When I was at 45 amp, I was getting undercut, which isn't ideal either. :headscratch: :headscratch: :bang: :bang:

Greg

For optimum results on tubing isn't it advised to back-purge the tube with argon to reduce sugaring?

Yes -- on HEADERS etc.... but of course not if you're building a roll cage. So "it depends"....

On headers etc you want smooth flow which means keeping the inside of the tubes smooth. Sugaring also leads to cracking and corrosion. Purging also gives better penetration.

Notice the WIRELESS foot control??? That is why I bought one at SEMA a couple years ago...

We're working around various "stuff" --- we're not usually sitting at a bench welding all day. It's just one LESS cable to mess with. I love mine!