Hi! I'm brand new to this site, although I've been watching the YouTube channel for a little while now. I love the videos, and I love learning more about the various processes. I'm not a professional welder, but over the last 15 years, on the farm, I've done more and more. I started out in life as an Army mechanic. Most all of our welding was done by a higher support level, so most of my early welding experience was with the little box stick welder we carried in our tool truck. Nowadays, I rely heavily on the 2004 Miller Bobcat I purchased new in the fall of that year. I also have some other Miller machines of various type and vintage, though I would have to say that my TIG welding is the weakest of them all, partly because I've not done enough of it, and therefore developed 'muscle memory' for the task of feeding filler metal into the weld puddle with a gloved hand. More recently, I'm in the process of finally drying-in my workshop in the barn I welded-up back when the Bobcat was sparkling new, and I've turned my attention back to TIG because that's where my key interests beyond the usual farm and ranch stuff lies. Specifically, I'm into R/C Airplanes, and I like being able to make custom exhausts, particularly for the scale warbirds(P-51s and similar vintage,) but I've not yet acquired the skillset to do it successfully. I have an aged 1991 Miller Syncrowave 350, and that's the machine I've used for TIG thus far. I'm working on trying to sort out why I am having so much trouble on the AC side. DCEN seems to work fine, and despite my less-than-proficient skill, I'm able to successfully put down beads on steel. Not so much on aluminum with AC.
Much of what I will be welding with AC will be very thin aluminum, in the range of .035-.049, 6061 tubing mostly. I'm practicing with .032 sheets right now, and making a fair mess of it. Some of it owes to my poor technique, but I have the sense that I may be up against some sort of AC or HF issue with this aging machine. All that for another day...
I'm learning a good deal from the YouTube channel, so that's a plus. When it comes to TIG, I have no shortage of questions, and despite the old saying to the contrary, some of my questions may be pretty darned dumb.
Here's a question... I get conflicting information about tungsten prep. My current welder, ye olde '91 Syncrowave 350, is of course a transformer machine. Some folk recommend I try to keep my tungsten tapered to a point, and some say I need to ball it on DCEP before flipping over to AC. Now, what I've seen of the inverter-based machines, a pointed tungsten works out, but I've not been having any success with that. Guidance on this item would be appreciated, as I have almost no experience with AC tig welding.
E3 is what I'm using. I'll give this another go either this evening or this weekend. I was watching a video by Mr. Tig that was updated on welding aluminum, and yeah, he said for a transformer machine, ball it.
So that's where I'm headed next. We'll see if I can make some progress!