My cutter started experiencing a weird issue where moving toward -X or -Y causes the plasma to sputter and fail penetration. It seems to be worse in specific regions.
I first thought it could be the air hose pinching but there is plenty of hose and no pinching is observed.
Then I checked pressure and the pressure is fine.
The failure is consistent and it only happens when moving toward -X or -Y.
Could this be some type of an electrical interference?
What is strange is, I’ve been doing the same cut for weeks without issues and now I can’t finish my cuts.
I don’t understand what could have changed?
Both of these shuttered loose, either I didn’t tighten them enough or they just worked loose over time. It happened back in december when I didn’t use the plasma for about 2 or 3 weeks and it acted like it was frozen. I couldn’t jog the machine anywhere, then I got it to move but when I cut a circle it would shutter really bad. Ended up being these parts.
What exactly do you mean by sputtering? Are you saying the arc itself is sputtering, or that it is binding at specific points when jogging?
If it is binding, check that the lead nut is not too tight. Crack the screws loose, then tighten them just a bit. Also, make sure your motor couplers are not slipping; you can check this with a marker.
If the issue is with the arc itself, I recommend we continue troubleshooting over email.
Please tell us more about your consumable age, what you are doing to cool and clean your air supply, and what your live voltage is while cutting. Also, check torch height when the cut starts to fail. Pictures of consumables too.
@TinWhisperer
Yes. That was many moons ago. Routine cut had no issues until recently.
@brownfox electrode and tip were relatively new when the issue started. I changed to new consumables since then. The Swirl ring has not bee replaced yet. It has no visible wear or tarnish.
I’m using an air dryer. I keep my THC at 103V.
I held the torch while it’s dry cutting the the square to check if there is any excess vibration or abnormal motion. None detected.
Checked angle of the torch relative to the work piece. It’s pretty perpendicular.
You keep your THC at 103? Are you setting nominal voltage to 103 all the time, because that would be a problem if you’re not adjusting for material thickness. There’s nothing wrong with smart voltage.
What are you calling an air dryer?
Even where it’s cutting through it appears to have excessive bevel, like the nozzle is blown out in one direction. I suspect you have a few issues.
This looks like a torch issue and not a table issue. Try rotating the torch in the mount and see if the issue follows the rotation.
Setting the nominal voltage to 103 for everything is not going to work at all. Setting nominal voltage overrides your programmed cut height. Once the THC takes over, it ignores your programmed cut height and moves the torch to whatever height results in 103v.
@ds690
Yeah that’s my next test. I’m gonna fire with the torch rotated 180°.
The torch is set to 103V because I’m cutting same thickness same material all day every day.
103V was experimentally obtained months ago and it’s what I have used to do my routine cuts.
SmartV was not looking pretty back when I was deciding between the two. The cut was rougher.
I have already run the cuts with and without THC to see if it made a difference.
@langmuir-jeff has suggested that I try the smartV with new tip and electrode.
Good news is I think I’m close to addressing this.
I turned the torch 180 degrees and did a straight left cut and right cut.
Now it fails X+ and cuts cleanly X-.
So this narrows the issue to the torch.
THC is not the problem
Not using smartV is not the problem
CNC is not the problem
Cutter is likely not the problem
Mounting angle is not the problem
Torch is likely the issue but the problem persists even with new electrode and tip.
When was the last time you changed the swirl ring?
So how important is the swirl ring? Do you ever replace it? Does it wear out? Does it affect the cuts? Lets see if this can help answer some or all of these questions.
The swirl ring does 5 thing when installed.
#1 Its a spacer between the torch head and the cutting tip
#2 Its a air seal between the torch head and the cutting tip
#3 Its an insulator between the torch head and the cutting tip
#4 It has air holes to swirl the air around the electrode to keep it cool (note: the hafnium in the end of the electrode becomes 3500 to 4000 degrees when cutting)
#5 it has air holes to swirl the air that comes out of your cutting tip to help keep a plasma flame uniform. ( Note: over air pressure will deform the flame )
Now to me the answer to the questions are YES the swirl ring is very important and should not be over looked. It wears out the same as other consumables and should be replaced if you start having cutting issues.
Well you didn’t list it as a consumable so it’s not a stretch to assume you don’t know what it was.
@mechanic416 was kindly pointing out its importance to you.
I can almost guarantee you 1/4 steel cuts at more than 103 volts so you probably want to do some more research and testing. Someone please correct me if I’m wrong, but I don’t think arc voltage varies that much from cutter to cutter.
I’m also not certain it was the cup, one slightly imperfect hole won’t wreak that much havoc on your cuts. Heck I’ve had blowback stuck on my torch and it still finishes the cut fine. Maybe I’m rusty, someone correct me if I’m wrong. I guess it depends on what you’re calling the cup too
I still think you have things to address before you stop running into problems, but if you’re happy now, great.
