TIG arc issue at start-up (Bzzzzzt)

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I have a '96-era Lincoln Square Wave 255 with fairly low miles. Weldcraft water-cooled torch, 1/16" thoriated tungsten. I use the machine for relatively low-amp bicycle frame building. DC negative with the high-freq start ON. I try to keep the electrode within 2mm of the work at start-up. I have a gas lens now, but it has done this with a conventional cup, also.When starting the arc, more often than not, the arc does not jump directly to the work, but creates a mini electrical firestorm that surrounds the electrode and inside the cup. This usually lasts for a second or so before the arc jumps down to the work. Sometimes, it takes a few tries to work properly. It used to help if I touched the filler wire to the work, but things seem to be getting worse.The little 'storms' give the electrode a frosty appearance which seems to encourage increased instances of this. After a while, the arc may jump out the side of the electrode, near the tip, rather than AT the tip. Frustrating.Sometimes, intermittently, it works fine.Any tips you could give would be appreciated.
Reply:I had the same exact problem with my sync 250 for the longest time, to the best of my knowledge it still does it now about 2 years from when it first did it.  Its just like you described, but no matter what I couldnt fix it.I tried changing tungsten, grounds, cups, gas lens, anything I could that would effect the torch to no avail.  Then suddenly it welds perfectly for the rest of the day.Have we all gone mad?
Reply:Sometimes I have issues with my old syncrowave 300 starting. The biggest issue I usually have is poor grounding, like the ground clamp is on a rusty spot on the bench, etc. Which seems to cause just what you're describing. The solution I have found is simple. Just touch the tungsten to the workpiece just before you start. Also you may want to check the spark gaps.
Reply:fortyone thirty has the right answer. Adjust the ground clamp to a closer spot, check for frayed cables or a worn clamp that's not making a wide area of contact.Then, physically touch the tip to the work piece lift it off a few mm's then try to start the arc. That "electrical fire storm" is just the high frequency acting like a mini tesla coil.  It happens on every welder we have here and its just a sign of a bad path to ground. I learned from a jetline rep that touching the tungsten to the work piece (while the torch is off) will dissipate the static and let you have a "fresh start" with establishing an arc.some machines also let you control HF intensity raising it can help.Also gas choice, cleanliness of metal, tungsten type and humidty will all play a part, anything that raiser the resistance between the work piece and the tungsten will have an effect.Welding EngineerCertified Scrap Producer
Reply:Several of these steps have been mentioned previously.Clean/reset the HF points.Increase the HF intensity setting if possible.Increase pre-flow.  Arc will have problems initiating if not in an argon shield.Touching/scratching the tungsten (with power off) will remove any oxidation which may have formed on the tip of the tungsten.  Most often caused (frosting) from too little postflow.Install a new cup.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:THANK YOU to everybody who responded. Sounds like I know what to look for, now.My machine lacks the adjustability that you mention, but I'll investigate the HF points (know zero about them) and will go over the ground to rule it out. I typically do tap the tungsten on the work prior to starting, because once I flip my helmet down, i can't see a thing until start-up.I really appreciate it!
Reply:Maybe a auto darkening helmet when the budget allows200amp Air Liquide MIG, Hypertherm Plasma, Harris torches, Optrel helmet, Makita angle grinders, Pre-China Delta chop saw and belt sander, Miller leathers, shop made jigs etc, North- welders backpack.
Reply:Originally Posted by Metarinkafortyone thirty has the right answer. Adjust the ground clamp to a closer spot, check for frayed cables or a worn clamp that's not making a wide area of contact.Then, physically touch the tip to the work piece lift it off a few mm's then try to start the arc. That "electrical fire storm" is just the high frequency acting like a mini tesla coil.  It happens on every welder we have here and its just a sign of a bad path to ground. I learned from a jetline rep that touching the tungsten to the work piece (while the torch is off) will dissipate the static and let you have a "fresh start" with establishing an arc.some machines also let you control HF intensity raising it can help.Also gas choice, cleanliness of metal, tungsten type and humidty will all play a part, anything that raiser the resistance between the work piece and the tungsten will have an effect.