Tig welder torch problem...

Date 08-06-2007 23:12

I am having a problem with using a longer torch on a Panasonic 300 amp tig machine.
If I use a 12 foot torch, the welder starts and welds fine.
If I use a 25 foot torch, the welder will do the initial hf start, but will not continue through to an arc.
I have tried several 25 foot torches, with the same result. Have tried ac and dc settings.
Any ideas?
-James Bauer

By Lawrence (*****)

Date 08-07-2007 00:43

Easy things that may help with the problem.

#1 Scotch brite your lug connections on the torch and work cable connection to your power supply and work clamp. A positive connection is going to be a big help.

#2 Increase high frequency intensity control to maximum.

#3 Decrease Tungsten Electrode by one size in diameter... Example 3/32" to 1/16"

#4 Make your electrode tip prep slightly longer and more slender. By this I mean make the length of the angle about 2 1/2 to 3 times the electrode diameter.

#5 Fresh collet and collet body. Toss the old ones and get some fresh copper in there to make the best connection you can.

#6 If you are using pure tungsten electrodes (green band) don't. Go to Thorium, Cerium or Lanthanum.

Let us know how things go after trying these easy steps.

By weldsman (*)

Date 08-10-2007 13:50

I believe it was a tungsten problem. I was using either pure or 2% thoriated. Using a lanthanated tungsten seems to have greatly improved the arc starting abilities and has gotten it welding. Woo Hoo!!!
Thanks for steering me in the right direction!
-James