Econotig problem

Welding some 20ga 304 stainless with my Miller Econotig. Since it's too thin I'm constantly turning the arc on and off. "Stitch" welding I
believe it's called.
Anyway it seems like an electrical connection/switch has melted or something because now it won't start the arc properly at low pedal. It sort of buzzes and has a really weak arc and makes a noise like when the arc won't start. It arcs ok with 3/4 to full pedal but that's way too hot.
I used to stitch weld all the time with my Hobart Handler but this is the first time I've really done it that much with the Econotig.
Has anyone seen this and know the fix?
Will the Econotig handle stitch welding?
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Actually it is called PULSED TIG. Stitching is short welds seperated by gaps, i.e. 1" weld, 2" gap, 1" weld, 2" gap...
Econotigs have a lot of problems. I had one for 5 years, and worked it like crazy before I upgraded.
Sounds like the high freq unit is getting unhappy. The Econotig has Capacitor Discharge High Freq, like what inverter TIGs have. So there are no spark gaps to clean.
It really sounds like it needs to go into the shop for a check of the boards.
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or the HF is arc'ing through the cable and has possibly went back in and shorted something. i had this exact problem with my esab 161 unit. esab started to install hf filters on the lead so that hf cannot get back in the unit. esab gave me a new unit with the filter in it.
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Actually on the EconoTIG it's a high voltage pulse by way of a transformer. The output of the HV transformer is fed to the torch by way of a coupling capacitor that passes the pulse but doesn't pass the DC on the torch back to the HV transformer. If the capacitor shorts the transformer burns up.
I know because I bought one cheap at an auction and that's what was wrong with it. The cap and transformer cost me about $150 and I added a small fuse inline with it so that if the cap shorts again it will blow the fuse instead.
I'm not sure that's his problem though because I had no arc start at all. He says his works at higher current... unless he's scratch-starting without realizing it?
Best Regards, Keith Marshall snipped-for-privacy@progressivelogic.com
"I'm not grown up enough to be so old!"
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