Background:
I'm in the process of adding to our in-house WPS's by adding some Spray Transfer procedures for when we have some thicker material in the mix. Mostly we deal with gauge tubing 16,14,11, some 7 and usually 1/4" plate or 1/4" angle tabs etc. so GMAW short circuit with 70s-6 .035" and 75/25 is the norm. We have processes for FCAW -g when dealing with thicker plates and heavier structural and that's fine, but switching over the machines (wire rollers, and tips and wand/liner if going up to 1/16" etc ) can be a pain and a time suck. we try to leave one set up but that doesn't always work out. its inevitable that when were busy and short on machines someone else will need whatever and switch it back. Plus now you have slag to deal with and cleaning welds and issues with inclusions if its multi pass etc... SO (re)enter SPRAY TRANSFER which talking with the floor guys they used to do more of but for whatever reason, don't now. There was an old bottle of 98/2 oxy in the rack so i pulled it out and hooked it to an XMT w a feeder. I started on straight CV and got it running nice. smooth, slick, even, clean and sexy looking fillet welds with great penetration and macroetch and break results on 1/2" and 3/8" plates and doing some larger radius flare bevels like the edges of square tube was nice too. I was happy.
So now i wanted to try 85/15 (C15) and 90/10 (C10) so i could hopefully find a single gas that could work for both our needs. that way someone welding short circuit on some gauge tubing could easily do some heavy plate quickly w a simple setting change.
I grabbed some scrap 14ga tube cutoffs and did some nice vertical fillets without much hassle. When i adjusted settings up to spray I was not as happy with my results. Sure I could make it work, but i felt like the 98/2 as soooo much easier and more forgiving. I was getting more spatter and didn't have the same fluidity and control. I'm trying to make it easier for anyone to transition into spray, not make it more of a challenge.
Background info over... So i thought why not go the other route, can i use the 98/2 oxy to short circuit? I tried it on some 14ga with a 17v/200wfs starting point and it seemed ok. some 11ga tube worked too but the weld profile was hard to get flat. high middle and the toe edges seemed almost like cutting in. I lowered the V and it helped but wasnt confident in it.
I spent a bunch of time reading on here and other forums and of course weldreality.com. and i thought it was time to initiate a new post to ask for feedback. Most of the discussion regarding 98/2 is for spray mild steel and stainless, which is understandable but what is everyones thoughts and or experiences using it for short circuit. Will is achieve my goals, or am i opening up another can of worms for potential problems. Thanks in advance.