[JustTheDad]

I have a couple of issues lately with my Dynasty 210dx and possibly with my new weldtec torch.

I don't believe the Dynasty issues started right when I changed the torch. I also don't know if they started before or after we had a brief 20 second power outage while I was welding.

On the Dynasty, about 1 out of 3 times when I go to start welding, the arc doesn't start. The gas flows, but no arc starts. If I wait until the cooler and fan have turned off before I start welding, it happens less, maybe 1 in 6 times, but it still happens. Also, the cooler seems to be running for a long time after I weld, even if I only make a tack weld, and the fan runs for 10 or 15 seconds beyond when the cooler shuts off which seems to be longer than previously. The welder does have 3 errors in the log. 7.5.3 is in all 3 errors, and 7.4.3 is also in error #3. Miller said that's a communication from the process control board error, and I'm told intermittent issues like it are very hard to track down. Also, new errors haven't been added to the log for a while even though the arc start fail still happens. I'm debating whether I should wait until the arc fail becomes more consistent or more errors show up before I drive it to the repair shop. What do you think? It does weld fine most of the time.

On the torch, it's a Weldtec i-head torch, the ball head, and I really like it. But, when I hooked it up to the new dinse connector, it leaked at the connection between the hot return hose and the dinse connector until I made it VERY tight. I also notice that as soon as the cooler turns on, the hoses jump. I have suspended the hose, but I notice that the hose jumped even when it was on the floor, and I don't remember the old hose doing that. The new hose set is only 12.5', and the old one, a weldcraft, was 25', but both are super flex tubing, so I'm not sure why I see it jump so much. It's making me wonder if there's a restriction somewhere that's requiring a higher pressure in the hose. Is that likely, or is this something I just never noticed with a 25 foot hose set?

Thanks,
Todd

[cj737]

Does your intermittent arc start occur on DC or AC? Is it consistently only on one polarity?

As for the hose “jumping” I’d venture a guess it has more to do with the shorter hose length (less volume to pressurize) in terms of you noticing it. I have seen air and liquid pressurized hoses move as they pressurize, but don’t have any experience with cooler hoses doing it, though I wouldn’t be also surprised if that’s the case here.

[JustTheDad]

Thanks, if the hose jump is just because it's shorter, I won't worry about it. I may swap the two dinse connectors at soe point just to see if maybe there's a narrow spot in the new one that I can't see.

On the arc, I'm only welding in DC on mild steel. 120amps most of the time.
Ground is good, and if I wait 5 or 10 seconds and try again, the arc will usually start.

[cj737]

Any chance the tungsten is contaminated? Have you by chance welded some mill scale and crapped up the tip? I have had the issue when on AC and the EP side of the arc blew oxide onto the tungsten causing a troublesome start. My “scratching” of the metal with the tungsten clears the issue.

[JustTheDad]

I go through 3 or 4 electrodes in any given hour because I am not very good, so that's an interesting question.

I will watch and see if it happens with a newly ground electrode.

Thanks!

[cj737]

You didn’t say whether you were using high frequency, scratch start, pedal control or a torch switch to control your amps. If it’s HF, then a contaminated tungsten tip will definitely cause arc start problems. If it’s really trashed, it may not even start on lower amps at all. Just an FYI…

[JustTheDad]

HF with a pedal to control the amps.

[JustTheDad]

So no failures to start if I change the tungsten when I contaminate it.
I'll watch the error log to see what that was about.
Thanks,
Todd