Cuts seem to be welding together

[Charlie6017]

Hello all, I am new to the forum. I recently built my own 6x4 cnc plasma cutter. I am using a lotos ltp5500d blowback torch plasma cutter. A proma THC with a floating z axis. Rack and pinion linear motion.

After a week or 2 I finally got everything dialed in and it was cutting really good. Then just 2 days ago my cuts seem to be welding together in some spots and I have to chisel them apart. I am cutting 16g steel at 30 amps at a speed of 95ipm. The only thing I can think of that changed is that the weather here in NY started to get really hot and humid a couple days ago. Today I bought a small desiccant air dryer and it didnt really make a difference. I have changed consumables to see if it was bad consumables but still doing the same thing. I am going to do another test soon and I will get a picture of what I am talking about.

Any help is appreciated.

Thanks,

Charlie

[acourtjester]

Crank up the amps and be sure the air pressure is above 80 PSI. watch this video and be sure the Proma arc voltage is set to cut at 0.060" very important to cut at the correct height and use the correct voltage to maintain it while cutting.

[Charlie6017]

Great Thank you, Yeah I think its the height. I dont know what changed but when I take the torch off the cnc and use it by hand it works perfectly. Im gonna watch that video. Appreciate the help.

[adbuch]

Hello all, I am new to the forum. I recently built my own 6x4 cnc plasma cutter. I am using a lotos ltp5500d blowback torch plasma cutter. A proma THC with a floating z axis. Rack and pinion linear motion.

After a week or 2 I finally got everything dialed in and it was cutting really good. Then just 2 days ago my cuts seem to be welding together in some spots and I have to chisel them apart. I am cutting 16g steel at 30 amps at a speed of 95ipm. The only thing I can think of that changed is that the weather here in NY started to get really hot and humid a couple days ago. Today I bought a small desiccant air dryer and it didnt really make a difference. I have changed consumables to see if it was bad consumables but still doing the same thing. I am going to do another test soon and I will get a picture of what I am talking about.

Any help is appreciated.

Thanks,

Charlie

Hi Charlie,
It sounds like your cut height is too high. I normally cut 16 ga. at 0.060" cut height. 40 amps, 150 ipm with my Hypertherm. Perhaps increase your amperage, and make sure you have good continuous air pressure at the machine. Also inspect your consumables to make sure they are in good condition. I have my air pressure set at 100 psi at the machine (while it is cutting).
David

[Charlie6017]

Thanks guys. It was the air pressure and the height. I changed voltage to lower the thc a little and raised the air pressure and just made a perfect cut. Appreciate the quick responses.

[adbuch]

You're welcome Charlie! Glad to hear that you've got it cutting again.
David