Cutting issues.

[Jb_engineering]

Hi, been having some cutting issues lately. I thought i had fixed it with fitting a new torch, but the problem has came back intermittantly. The arc seems to stop for a second and restart again, hench not completing cuts, but then will start cutting fine again.
New torch added, new consumables, clean dry air. I didnt know if anybody has a fix for the issue.
Thans and look forward to replies.

20240926_160606.mp4

(180.12 MiB) Downloaded 12 times

20240926_160606.mp4

(180.12 MiB) Downloaded 12 times

[adbuch]

Chris - as I recall you installed a replacement torch that was not the exact same model as the one you were using before. Is this still that same torch, or were you able to get an exact replacement? It is possible that this could be a problem with your plasma cutter, or maybe your torch trigger circuit. I would try testing by using a hand torch and do some manual cutting to see if the problem still persists. If it does, then I would suspect a problem with your plasma cutter. If it cuts fine using a manual torch, then I would suspect either the new torch or the trigger circuit for the machine torch.

You might also try swapping out the plasma cutter for a similar model and test to see if the problem goes away (or not).

David

[Jb_engineering]

Its now the correct torch david. It cut half of this job fine, then started to have issues, let it run for a few minutes like the video shows (arc cutting out and restarting) then it finished the job fine. The problem doesnt seem consistant, and only does it sometimes.

[adbuch]

Nevertheless, I would still do the tests I suggested to see if it has any "arc cutting out" issues under any of those scenarios.
David

[acourtjester]

Looking at the video it looks like the torch fire and stops for an instant at the start then restarts. As David suggested it may be in the trigger circuit.
Maybe you could rig a parallel circuit with a led to see if its the controller signal dropping or internal to the plasma unit itself.
On the outside chance do you have the unit in the "Expanded metal cutting" position??

[adbuch]

Looking at the video it looks like the torch fire and stops for an instant at the start then restarts. As David suggested it may be in the trigger circuit.
Maybe you could rig a parallel circuit with a led to see if its the controller signal dropping or internal to the plasma unit itself.
On the outside chance do you have the unit in the "Expanded metal cutting" position??

Tom has some great suggestions! I like his suggestion to wire a test light to the trigger circuit.
David

[Jb_engineering]

Thanks for the imput. Ive used it today and its cut fine. Its strange as sometimes it runs faultless. Surely if there was a problem with the trigger circuit etc, the problem would be there all the time?

[adbuch]

Thanks for the imput. Ive used it today and its cut fine. Its strange as sometimes it runs faultless. Surely if there was a problem with the trigger circuit etc, the problem would be there all the time?

That's why they call the "intermittent problems".
David

[SegoMan DeSigns]

Thanks for the imput. Ive used it today and its cut fine. Its strange as sometimes it runs faultless. Surely if there was a problem with the trigger circuit etc, the problem would be there all the time?

That's why they call the "intermittent problems".
David

Those are the funnest to diagnose or tell the mechanic about...

[acourtjester]

With intermittent problem there can be different reasons for them. Broken wires the make or break contact with motion, plug and jacks can have small amounts of corrosion or dirt on the pins. Or the plug may not be fully connected for the pins to be engaged in their sockets. If you connect the CNC connector at the rear of the Hyperther plasma to operate it and disconnect after, you may not be tightening the plug enough. It has a inconvenient location and it may not be tight each time you use it.

[adbuch]

With intermittent problem there can be different reasons for them. Broken wires the make or break contact with motion, plug and jacks can have small amounts of corrosion or dirt on the pins. Or the plug may not be fully connected for the pins to be engaged in their sockets. If you connect the CNC connector at the rear of the Hyperther plasma to operate it and disconnect after, you may not be tightening the plug enough. It has a inconvenient location and it may not be tight each time you use it.

Tom - those are some great ideas of additional areas he can investigate.
David

[acourtjester]

thanks just trying to give a little direction, may not be the solution, but you got to start somewhere.

[Jb_engineering]

Ive noticed today, that the plastic threaded part has a split all the way down. This pic isnt my pic (i forgot to take one). Would this be a cause of the faults?

[adbuch]

Let's see a photo of your actual ohmic cap showing the split.
Thanks,
David

[Jb_engineering]

This is my one.

[adbuch]

I can't tell from your photo, because when I zoom in the resolution is tool low to see the detail of the "crack" - which looks almost like a factory groove. However, if the replacement ohmic caps do not have this "crack" - then I would try a new one. Does your shield screw on tight?

David

[acourtjester]

That almost looks like one for a different torch. have you checked the part number against on my 65 the part number is 220953 and I think is used on the Duramax torch used on many Hypertherm units. Could that be a knock off brand?????

[adbuch]

That almost looks like one for a different torch. have you checked the part number against on my 65 the part number is 220953 and I think is used on the Duramax torch used on many Hypertherm units. Could that be a knock off brand?????

Tom - he is not using a Hypertherm cutter. He discusses his plasma cutter here.

viewtopic.php?p=239051#p239051

David

[Jb_engineering]

It isnt supposed to be there david. Ordered a new one to see if its the problem.

[adbuch]

It isnt supposed to be there david. Ordered a new one to see if its the problem.

Chris - Let's hope the new one fixes your problem. Let us know.
David