Random not cutting all the way through material (CNC)

[Unbrakeable]

Hey, was hoping you guys might be able to point me in the right direction regarding an issue that has just popped up over the last 3 weeks.

My machine will be cutting files that cut fine 2 months ago, and midcut sometimes it will just not cut completely through the material for an inch or two, as though the torch tip is too far from the material (its not). Its never in the same spot, sometimes it doesn’t happen at all.

My air setup consists of an ac condenser to cool the air and two water traps (one pre tank and one post tank) as well as a desiccant dryer on the back of the hypertherm powermax30 machine.

I have tried:

New consumables
Attaching the ground right to the material
Grinding the millscale off the material for the ground
Stopping the machine when the issue occurs to confirm torch height

I do not believe it is a speed issue as my settings worked just fine previously. I am leaning towards wet air still, though I am not sure why it has just become apparent lately.. Also am planning on swapping out to a new air hose as maybe mine is degrading?

Any help is appreciated!

[djreiswig]

Do you have a pressure gauge at the inlet of the plasma after all of the filters? Could be an air pressure issue.

[adbuch]

What control software and controller are you using? Are you using some sort of torch height control that monitors arc voltage? If so - does this problem persist when you disable your thc? . Fluctuating air pressure would also be another possibility. I run 100 psi at the air inlet to my plasma cutter with the cutter running. An intermittent connection with your torch trigger control wires is also a possibility. Are you using a hand torch or machine torch?
David

[weldguy]

I think you may correct about the wet air. A good way to confirm is look at your used consumables and if you see grey or black staining swirling inside the nozzle and around your electrode your air is def contaminated (comp. oil, moisture) and new lines, better filtration should be used. Even once you get the air cleaned up there will be some time before you clear out the long torch lead of its contamination.

[xnaron]

I've seen people use the Motorguard M-60 https://www.motorguard.com/air_2_9.html . I am thinking of trying one. I have no idea how long the filter will last. It will be most likely depend on how clean/dry the air going into it is. I live in a pretty dry climate with low humidity so might last longer for me then someone on the coast in a humid environment.

[Rodw]

In my climate, dessicant driers and motorguards were totally useless. Fitting a refrigerated drier to my air supply solved all my problems.

Now if something goes wrong like that I know its a worn out electrode in the torch