Rising cut height during cuts

So I have experienced both of those scenarios with the cutting but definitely more so on the latter. Most of the time the arc will continue while raising during that loop and then will move to the next loop and cut fine. Very sporadic. It will usually cut correctly once I rerun that loop. Just doesn’t look as great. I also noticed the kerf if some areas of the cut were much larger while observing. Ruined a 30” sign. I checked that screw and it’s on there pretty tight. I have jogged the torch up and down and did see the IHS green light turn on once it tapped the material. Live reading was around 97.0 nominal reading was 110.8

30a tip running at 27 amps gives me the best cuts when working correctly :man_shrugging:

Are you running smart voltage or using a nominal voltage? If using nominal voltage, how are you determining what to set it to?

I haven’t been using smart voltage because it says for 14g or thicker. I haven’t entered anything or changed any of those settings since I bought the machine

Try it using smart voltage.

What do you currently have written in the nominal voltage line?

Or entering a nominal voltage in this range and give it a try.

I did some small test cuts tonight and i’m pretty sure turning the smart voltage on was the solution. Huge improvement Thanks! I wonder why langmuir says to not use it for 16g

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That is great.
What voltage did you have written in the nominal voltage box before switching it over to smart voltage?

I run nominal voltage numbers for every cut I do but I also have a hypertherm who puts nominal voltage numbers in their cut charts. The only way for you to get nominal voltages would be run some test cuts without the THC ( I’m not sure if the live voltage stays active without the THC turned on z axis might have to be just unplugged so it still gathering that data) at the correct height and observe what the live voltage averages and then use that for your real cut.
If you had a random nominal voltage number written in there the THC will just try to chase it up or down to get there.

My hyperthermal run nominal voltages from about 78 to 131 depending on the thickness of material and the torch height.

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It was set at 110.8 Going to cut out a sign today while on smart voltage and ill see if it made a difference. I will post a picture

Not sure if these pictures will upload but here you can see that it did it again. I was able to rerun that loop and get it to cut. Just looked awful. I can clean it up. I noticed on my y axis’ rails some of my bearings are loose and some are too tight. Could that be causing this?

What condition is that nozzle in it looks like it’s gotten hot.

How’s your air supply? I might check your desiccant cell and see what the condition is like.
Wet air can definitely kill a set of consumables quick.

That was a fresh nozzle and electrode.

You don’t want all the bearings tight to rails at all. Some will be loose, and some will have a little resistance at different locations to rails. Go back and reread through the Langmuir setup instructions as to how to set preloads on bearings.

I’ll check the desiccant when I get home. Is there a way to test for moisture in the air?

That’s exactly what I just did :+1:

You could test your normal atmospheric air with a hygrometer.

But to test your moisture content in the compressed air you would need a pressure dew point monitoring system.

Some desiccant cells will have a paper indicator that’ll turn from Blue to Pink there is also some types of desiccant beads that turn from Blue to Pink.

The other alternative would be to take some brand new dry beads and take your beads out of your desiccant cell,use a thermal imaging camera to see how much of a temperature difference is between the two. it’ll be obvious which ones are wet.
The wet ones Will be cooler because of the latent heat of evaporation that would be occurring.

I have two packs of beads that I rotate every other time I cut.

Edit. I scrolled back through some of my thermography photos and found a comparison between dry and wet desiccant.

And here’s a picture of the wet desiccant spread out in a tray. And a cell of desiccant that’s wet.

The cooler (blue) part of the images comes from evaporation.

What nozzle is that? That doesn’t look like the right nozzle for a PTM60 torch.

Edit: maybe it is, it just looked like too long of a taper on the end This pic is a standard nozzle on the left and a shielded nozzle on the right. The shielded one requires a different cap.

Yeah all my consumables come from George on here so I’m confident it’s the right nozzle. I’ll check the desiccant beads and see if it’s a moisture problem which is what I’m speculating. I’ve been doing several test cuts for the past few weeks and it seems I’m blowing through the consumables. Im totally new to plasma cutting. I did spend the time putting together what I thought was a good air drying system. Honestly I hope that is the problem. Should be an easy fix :man_shrugging:

This is the standard you are trying to achieve.


And this is a time of year where it’ll be quite a bit of water vapor in the air.

I noticed you’re cutting a sign for Dallas, are you in Texas? North Texas? Because it’s been really wet the last week. Super rainy and humid around North Texas into Oklahoma and Kansas. Did this crop up during the weather we’ve been having? Also, can you put a multimeter on the lines to see in real time what the voltage is as it cuts? It’s possible you have a voltage leak from somewhere; either a leak from a componant that is giving too much voltage, which seems most likely considering the symptom of the head going up; or, perhaphs a voltage leak from the cutting circuit going to ground along the line to the electronics. Just a theory.

Yes I am in waxahachie just south of DFW. I will test the voltage on my next cut. I’m pretty confident that my air is not as dry as I thought. Just purchased the refrigerated air drier from HF and an additional filter to mount on the back of plasma cutter. Finger crossed. Regardless I know I will get all the kinks figured out because this forum is incredible. Thanks!