I started my first cut on a piece of 1/8 mild steel. It was going great! But the 2 foot square piece I was using was a few inches short of allowing the cut to be completed. I mainly wanted to see if I had everything dialed in correctly. It was. So, I ran to a steel surplus place for a larger piece of steel. Found something big enough, but it was 3/16. Ehh, what’s another 16th. I placed it on the table and ran the program again. The torch gingerly moved over to it’s start point, just like the 1/8th trial run and dry run. It began to cut a start hole, then it stopped. The air continued until I cleared the following error message. LS -THC Has detected the torch moving before sensing voltage. I rewrote the the program to match the 3/16 change. The data had not changed significantly. I welded the holes shut, smoothed it out, and ran it again. No change. I know it’s something simple I did or didn’t do. Any suggestions? Thanks.
Did you reset your torch height as now your torch is .065” closer to the metal?
Thanks for the suggestion. For the 45a it looks like everything from 20 Ga to 1/2 is commonly 0.06 for torch to work, and 0.15 for initial height. So I didn’t change it. Pierce time delay for 0.125 is between 0.3 and .04. For 0.188, it’s 0.5, which is where I have it. So, I did adjust that one. Cut speed for 0.188 is 85, and for 0.125, it’s between 190 and 140. Lots of numbers, but I think I’ve prepared it for the 0.188 approach correctly. I went and bought a full sheet of 1/8 today, so if I can’t find a cure, I’ll just cut into that.
Pierce delay at .7 and try it again. Make SURE you have 75 psi to the cutter during the entire cut. Not 60 or 65. 75 psi..
Make sure your work clamp is on the metal you’re cutting.
It doesn’t matter what the chart says, .5 sec is not long enough for 3/16” steel on a Langmuir table.
Firecontrol counts the delay from the time the signal to fire the torch is sent. Most charts count the delay from when the torch actually fires. You need to add a couple tenths of a second to all of the delays in the chart.
You should always manually check torch height between the cutting tip and the work piece every time you change metal thickness.
Good suggestion. Just to be sure, I’ll look for some feeler gages.
Holy cow! That is significant. Bigdaddy kind of said the same thing. Some great feedback here. Much appreciated! I’ll let you guys know how it turned out.
Thanks Bigdaddy2166,
Sound like good advice I’ll make those changes. Too late to try it tonight though. That big compressor will wake up the whole neighborhood.
George you should write a book. Most of my bookmarks are George ‘isms… I marked that one first time I have read that. But have not really needed it. 96% of what I have cuts has been 14ga.
Thanks for sharing your knowledge and being patience with some of us thicker headed individuals.
Given your advice, and some research, I’m going to use these perimeters. Can you take a look and let me know if they’ll work. Thanks.
Cut Height= (0.06)
Pierce Height= (0.15),
IHS Springback (0.02)
Pierce Delay= (0.7)
Nozzle= (0.0625)
KERF= (0.0625)
Cut rate= (85ipm),
Lead in= (85ipm)
Lead out= (85ipm)
CUT PWR= (45)
PIERCE PWR= (45)
PRESSURE= (75psi)
It’s possible I fall under that “thicker headed” title. Who knows? 
This CNC thing is new to me, but I’ll get it. Just a matter of time. With that said, I really appreciate all the help and knowledge anyone has to offer. Unfortunately I ran out of time today to try the suggestions from last night. So the test results in limbo. Hopefully tomorrow.
Good news. I rewrote everything. It worked like a charm for 1/3 of the project. Then the same thing. Weird. Looks pretty good so far though. It cut about 30 out of 100. I’ll increase the work gap. Feeler gage shows a 0.05. The final message says to run from the line number loop. I’ll see if I can tomorrow. Error Message 1, Torch moving before cutting voltage sensed. Message 2, Run from loop. Start from cut loop that starts at line 2153. Message 3, Same as the first. Message 4, Run from loop identical. Tomorrow, I’ll weld in that hole and try it again. The ground clamp was connected to the project. Pressure is at 75 psi. I’m going to increase the work gap.
