I am new to TIG welding, but have used MIG and Arc welders for years. I have a new machine, a LOTUS CT520D. I have read the manual that came with it, as well as some on line resources. I am ready to make my first weld.
I am not clear on where to position the tungsten rod with respect to the end of the cup. I have seen some photos showing it up inside of the cup, others with it sticking out. Is there a set or reference dimension for the position of the ground tip of the rod, and does it vary for different metals? Maybe a formula or chart?
Any help will be appreciated.
Rule of thumb is usually no more stickout than the diameter of the cup. Cup numbers are in 16ths of an inch, so a #7 (7/16") you wouldn't want anything more than 7/16" stickout. There's no real benefit of having long stickout if you don't need it so try and keep it an acceptable distance within the cup diameter that still allows you to see and have clearance.
"Your welds should sound like bacon. If your welds smell like bacon, you're on fire." - Uncle Bumblefuck (AvE)
Exactly on above. What is equally important is arc distance (distance between tungsten tip and metal you’re welding). Keep that basically equal to the diameter of the filler rod for best results. The longer the stick out (as is required for reaching into tight spots) the larger the cup you need and the more gas flow CDH.
I generally keep my tungsten stickout to about 1/8" unless I am trying to get into a hard to reach spot. That allows me to see the tungsten position in relation to the puddle. If I need a longer stickout, then I will switch to a gas lense with a larger cup. Hope this helps.