Feeling a bit better today, still have a cough like an emphasema patient, but the nose has slowed down.
Worked on steel bars today, trying to push out the last 20 before I fire up the powder coat. With a change in material from Ti to steel, I have to swap out a bit of equipment on the water cooled torch, so I thought I'd share a bit.
As I've mentioned previously, Ti welding must take place in an oxygen free environment to avoid embrittlement caused by oxygen contamination at temps above 800 degrees. To accomplish this, I purge the interior of the tube with argon and use an extra large diffusion cup to create a "shower" of gas in the area of the liquid weld puddle.
Below, the equipment for Ti is on top...you can see the greater diameter of the cup and the diffusion screen to insure consistent gas coverage. The next size down is a diffusion set up for steel, using a smaller coned cup and diffusion screen built into the collet body. The smallest and non-screened set up is a standard cup/collet body/collet for steel work.
Tacking in the inside corners, I got my moneys worth out of this piece of filler rod...