Those following this blog might have noticed earlier, that I actually do quite my share of welding, but for as long as TIG is concerned, I am doing mostly stainless. Now with the TR1 engine build I have a situation, where I have to dust off my old aluminium welding knowledge and get to it. In order to do that I had to do a couple of things to get that Stahlwerk 200 AC/DC Puls working as it should.
To be fair and just to get this out of the way, my TIG set isn't the most expensive in the world and with it being an analogue setup, if it weren't for the inverter setup instead of a transformer and the HF-start, I could have been straight out of the 70ies technologically. After doing some welding in the last few days it's actually a whole lot better than I dreaded, but there's a couple of catches to make it work, some of which are down to somewhat insufficient q.c. on the manufacturer's/retailer's site. The following points are therefore not meant to shed a bad light on the machine, but to give you some info on how to professionally do some fault-finding, if it simply doesn't work.
1) If you want to use a footpedal and NOT use it as a on-off switch, turn all the amperage dials on the machine to zero.
2) At least on my footpedal the pedal-stop was stopping the pedal to go all the way down. Actually it was more set up to be around the 50 percent mark.
3) The potentiometer on the footpedal doesn't seem to be perfectly matched with the machine, I can only turn it up to 8-ish or so or it will turn the footpedal into an on-/off-switch again. Only this time it's pedal to metal means full-throttle really.
4) Impulse-amperage can and has to be set at the machine and once it goes over zero in AC-mode, it means that display shows some rather random numbers.
5) If you want to weld AC, make sure pulse is set to off, or the pulse generator will randomly interfere with the HF-start, which makes lighting the arc a bit of a gamble. Once that is covered, the HF-start is really nice.
6) On the subject of AC-welding. The manual explicitly states that in AC-mode the machine can only do 100Hz as max. frequency. Turning the knob to a value higher than that will have the pulse-generator interfering with the welder, resulting in a terribly flickering arc.
7) Pulse-width is marked in "Everlast"-style, displaying "DCEP" or cleaning, i.e. 80 percent on the dial means 80 percent positive or cleaning action.
8) This is slightly more general, but worthwhile to know: Up-slope and down-slope only work in 4T, which basically means: A proper TIG-welder uses a footpedal.
So what's my verdict: It's a proper oldskool machine in the spirit of one of those half-ton lumps that used to clutter workshops in technical colleges and secretly died out many years ago with the advent of modern inverter technology. So if you learned the welding craft on one of those, you'll love it. The arc is nicely stable on even the lowest settings and once you get the hang of it, it truly is quite a good machine to use. To be honest though, there's a few things, I really want in my next machine, which incidentially means, I'll finally go digital on my next TIG set: More than 100Hz in AC-mode (because 150+Hz really makes that arc tighten up), up- and down-slopes working in 2T-mode, multiple wave-forms in AC and pulsing beyond 200Hz in DC mode for working on really thin tubing.