[ajlskater1]

So one of the welders at my work will not strike a arc anymore. Its a miller dynasty 350. If you hit the foot pedal the preflow willstart but you get no arc. The only way I can get the thing to arc is by sticking the tungsten to the table, hitting the foot pedal like 10 times then it will arc, but obviously thats no good cause then you junk your tungsten. Anyone have any ideas? I am thinking the high preq went out on it?

[Otto Nobedder]

Probably right about the hi-freq, but just for fun, try putting a different (known good) torch on the machine. I've had a water-cooled torch do this for reasons unknown.

Failing this, check the manual on cleaning and setting the spark-gap. If neither helps, it's probably a circuit board.

Good luck,

Steve

[ajlskater1]

thanks well I will check that stuff out. But now I am leaning more towards a ground issue. I got the machine to arc by striking it on the ground clamp itself and then it would weld fine until you let the post flow end, then you would have to strike a arc on the ground clamp again. This thing has got me even more confused now. By the way have any on you guys that run water cooled flex heads, have issues witht he torches heating so bad you can hardly hold them with gloves on and also warping the hell out of the collet? Usually only happens on ac. Never used to happen with our old solid body ones.

[allessence]

dirty arc gap inside the machine.. These points need to be cleaned every so often.. If the preflow is on but there is no HF then you can just about bet your gap is dirty.

[nova_70_383]

make sure you not on lift arc, u want hi frequency start! u probably checked this but thought i would throw that out there. other wise if you were on hi freq start, try lift arc and see if it works correctly. maybe you could use it this way until it gets fixed if there is a problem.

[ajlskater1]

Hey thanks for the help guys. I finally got the problem figured out well kinda anyways. I cleaned the inside of the machine cause it was really dirty and someone had messed with the the preflow and put it to 2.0. So I put the preflow back to .2 and everything is back to normal. But I do have one more question. For the guys that use the dynasty 350. Do you guys ever have to scratch the tungsten on your table to get the arc to start? Is this a common thing? Like everything will be working great crisp solid starts, then you hit the pedal and nothing, but if you scratch the tungsten on the table it goes back to working fine. This does not happen often but it does do it on all of our machines.

[allessence]

Dirty arc gap... Set you starting voltage higher.. Yes sometimes in the past I have had to scratch the tungsten on the article first. Not since i cleaned it though.