AC stick weld with Squarewave TIG

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Has anyone with a squarewave tig tried to AC stick weld with it? Below are some results.After Ricks' post I thought I'd give the +/- and AC penetration stick test a go, but his thread was closed before I got my post ready (I've been covered up at the shop)... I too had trouble with the 7014 slag not being able to wash over the weld edge and it built up thick making it hard to remove. I don't remember ever doing a fillet with 7014 and I got a lesson!I also discovered square wave tig machines make whup a$$ AC stick machines!!!!The coupons were 1/4" shear drops stolen from the neighbor. The electrode was 3/32" 7014 set at 82-84amps  DCEN, DCEP and AC in that order. The part was allowed to cool and rotated and welded again on the other side. I made sure the Straight/Reverse/AC welds all matched up (kinda close anyway).The etch was done with 5-10% nitric.I'll look with the big eye tomorrow but just by the pics I'd say DC straight works pretty well with7014.I also did a coupon with 6011 I'll post later.Matt Attached Images
Reply:The square wave will pretty much apply to the AC cycle of the machine only. Usually the square wave machines run at lower voltages then the sine wave machines from my experience with them. I had a square wave, Hobart with the amp and voltage gauges for TIG. Never used it for stick though. But I know from actually putting a voltage meter to the sine wave welder while it was running, making a weld, that the sine wave machines run at higher voltage then do the square wave machines. That usually means a more stable constant current. Much like a heavy duty generator type welder gives you. I have done miles of Stick with mobile welders, and also with the small three phase generator stick welders. And their output was just amazing compared to the average small transformer ARC welder. Once you light up the rod with a good power source you almost cannot put it out. Something I found was not true with weak portable ARC welders and smaller electric ARC welders. A four inch ARC is not uncommon during the course of a day, with a good machine. I used a few good electric transformer powered welders too that were very nice, big old giant ones, no readable name, fifty coats of paint on them. Ha-ha.        Sincerely,             William McCormick
Reply:Hi Matt,Yeah my polarity thread got closed - likely too many negative comments from vocal 'experts' who were only too delighted to poop on my amateur efforts but who couldn't be bothered to contribute by burning a rod themselves.  What can you do?Too bad as we'd yet to hear from distractor on his repolish/etch.I'm still working on it too - completed a better third attempt but didn't post.I'm set for a fourth attempt... hopefully that will provide the consistency I need. Originally Posted by Matt_Maguire I too had trouble with the 7014 slag not being able to wash over the weld edge and it built up thick making it hard to remove.
Reply:Originally Posted by Rick VHi Matt,I hesitate to show my last 3/32 inch, 80 amp, 7014 welds...   Oh well, more practice.Looking forward to your 6011 results.
Reply:Darn!I just took a good look at the pics and I think I may have marked the DC welds backwards...DCEP should have a slightly convex shape and DCEN should be flat to slightly concave?The AC looks pretty flat, I'll check today (I also stamped them each side of the cut line).Matt
Reply:Originally Posted by Matt_MaguireI just took a good look at the pics and I think I may have marked the DC welds backwards...DCEP should have a slightly convex shape and DCEN should be flat to slightly concave?  The AC looks pretty flat
Reply:Matt,On a squarewave machine (at least on the Miller Syncrowave's) the balance control serves as a "dig" control when arc welding.Adjusts the "arc force" and can make starting easier depending on the setting.What several knowledgeable posters were trying to tell Rick in his previous thread, which he chose to ignore, is that there are many factors besides just DC+ or DC- that go into determining the amount of penetration.  Until a consistent bead is produced, no result is conclusive.Nearly every rod out there has it's own characteristics about how it likes to be run. If the rod is not run using the correct technique, the results are further flawed.Interesting "experiment" but the "results" are meaningless.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIMatt,On a squarewave machine (at least on the Miller Syncrowave's) the balance control serves as a "dig" control when arc welding.Interesting "experiment" but the "results" are meaningless.
Reply:Sundown is right as to the balance control, but if you really want to try something you could put an AC stick electrode in your tig torch, and run it in AC TIG mode.  That way you will be able to adjust the balance control.  I dont know if you would be able to turn the HF off or not on that machine in AC.That would be an experiment worth trying.Have we all gone mad?
Reply:Originally Posted by Rick VIt's not easy to tell from the first photo showing the three welds but it looks that way.It's easy to get turned about... good thing you stamped them each side of the cut line.  How long did the 5-10% nitric acid take to do that etch?
Reply:Originally Posted by sn0border88Sundown is right as to the balance control, but if you really want to try something you could put an AC stick electrode in your tig torch, and run it in AC TIG mode.  That way you will be able to adjust the balance control.  I dont know if you would be able to turn the HF off or not on that machine in AC.That would be an experiment worth trying.
Reply:Matt,My first Syncrowave (1977) had a balance control and it also controlled the dig/arc force in stick welding.I wouldn't be surprised to learn that your machine does the same.  Try turning the balance all the way counterclockwise and strike an arc.  Then turn the balance all the way clockwise and strike an arc again.  I think you'll find that the arc is easier to start with the balance cranked up.PS.  If you think the arc is nice on a squarewave machine, you should get your hands on an XMT304.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Originally Posted by SundownIIIMatt,My first Syncrowave (1977) had a balance control and it also controlled the dig/arc force in stick welding.I wouldn't be surprised to learn that your machine does the same.  Try turning the balance all the way counterclockwise and strike an arc.  Then turn the balance all the way clockwise and strike an arc again.  I think you'll find that the arc is easier to start with the balance cranked up.PS.  If you think the arc is nice on a squarewave machine, you should get your hands on an XMT304.