LTEC Heliarc 250 pf squarewave machine setup/use questions

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I was able to pull all the pieces off the machine to modify them. I did the mods with my mig...a different welder.I've got it all set up now and i've been practicing with it. I have some questions for anybody that has used a transformer machine like this in the past to tig...1. The hf start seems to activate frequently. The arc will start and then it will stop but I do keep hearing it go on and then off. Is this normal? I'm welding in DCSP with the hf switch set to start. I checked the gap and it was right at 0.025" which is what manual specifies. Something I am doing wrong maybe when welding? I assumed the hf start was a timed feature but it is acting like it activates on current or voltage.2. The arc is very noisy...when I seem to get the puddle right and the hf stops, it will buzz seemingly normal but there are also times when it pops like it's unstable and jumping around. Even when it's at it's best, it's still loud. I just put a new gas lens, #8 cup and 3/32" tungsten in the torch. Its sharp and free of contaminants. I have the electrode proud of the cup by approx. 3/16". I've seen videos and tv shows where people are tig welding and it seems like the arc is silent. Is it because they are using inverter machines?3. The arc does not seem properly focused. It's quite wide and and even seems undefined at times. I've tried different points on the tungsten with no improvement.Is there something wrong with my machine or am I just not using it properly? I'm new to tig welding but something seems off. I've done a good bit of mig and I can set that machine up "by feel". The tig machine has a foot pedal amp control. I have the dial set to 70% on high range (20 to 320 amps) so I should have 30 to 230 amps on the pedal. I have been welding 3/16" cupons together.oh yeah...one other thing. There is an arc force dial on the machine. The manual says it's not used for tig, only arc welding so I have it turned all the way down. I did not try jacking that up at all.Any help and/or advice is appreciated.
Reply:I just messed with it some more. I'm convinced something is wrong with the HF functionality. I watched the sparks between the gap when i hit the pedal and there is plenty of activity. I'm wondering if the points are mis-shaped or corroded. There are many arcs flying between there. Also, sometimes the arc at the torch wont start even though I can hear the firestorm between the points. should there only be 1 focused arc between the points? It's like the HF arc is too scattered between the points and can't get to the torch. If I hammer on the pedal and get a good puddle going the HF will stop though so it seem like it's trying to work.
Reply:The hf points on that machine also adjusted for hf intensity. The larger the gap the more intensity. Id check the hf points for corrosion and a faulty hf on/off switchMiller Dynasty 200DXMiller Spectrum 250DMiller Millermatic 200Bunch of old blue dinosaurs....
Reply:I called ESAB support this morning. They indicated that the HF should stop once the arc is established. He thinks it could be a faulty main PC Logic board. Apparently it controls the on/off of the HF. They gave me the name of a semi-local repair shop that can rebuild the board. I called them and they are definitely familiar with this machine. Although he did indicate that the HF is started when the voltage rises and stops when it drops so...it's a function of load on the machine I guess.Dumb question here and I'm certainly opening myself up for some criticism but am I just *****footing the pedal so I can move my hand more slowly? It's a bit pricey to get the board repaired.Any help?
Reply:I found a post out there where a bad torch was causing similar symptoms with the HF start.http://weldingweb.com/vbb/showthread.php...em-TIG-300-300Last edited by Kimmer71; 09-27-2013 at 05:07 PM.Reason: add link
Reply:Have you tried it on AC?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelonHave you tried it on AC?
Reply:Originally Posted by Kimmer71Tried all modes with stick and it works fine. Tried AC with tig (on steel) and got a 1/2" wide circular arc. I did have the water flow reversed but no better after correcting.In DCSP with HF start, the arc jumps off the side of 1/8" e3 tung even after the HF stops. its weird and seems like a tung or torch issue? I have a 1/16" red tung that I tried but same results. I think the torch sat for a few years without use. Could an eroded cable inside the hose cause this? I'm perplexed. I thought maybe a bad ground but I cleaned and clamped the ground directly to the piece I was welding on.
Reply:Do you have the polarity correct?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelonDo you have the polarity correct?
Reply:Originally Posted by Kimmer71I believe so...DCSP on the selector.I practiced with it more yesterday after reading as much as I could and it made a big difference. I don't think there is anything wrong with the welder...just inexperience with the weldor. I plan on trying some different types of tungsten. I'm using e3 right now. I found that extending the post flow timer out to 5 seconds or so helps keep the tung clean.Anyway, I'm having much better luck with it. Thanks for the help.
Reply:Well...They are labeled "electrode" and "work". I have the torch hooked to "electrode" and the ground clamp hooked to "work".