Torch catches on slag of pierce

Huh? Ok, from the photo I was guessing that it hit at the end causing the little hook turn, and preventing it from finishing it off. Goes to show how little I know.

Hi

On larger industrial level plasma cutters there is a section of the torch height profile for raising up over the pierce slag puddle before going to the actual cut height. This is usually done on the beginning of the lead in for the cut so the torch is at cut height by the time it gets to the work. This will take some integration with your post processor to make it work. The usual work around is to pierce all the start points on a thick sheet then stop the machine and clean off the dross. Then the machine is restarted to make the cuts. While some what cumbersome this can be done with hand edited files.

John

This is a problem I have experienced almost every time I try to cut 3/4" material. I have a HT PM85 which --according to the specs-- is capable of piercing 3/4". I follow the manual to a 'T' regarding Pierce Height, Pierce Delay, Etc. I'm using Sheetcam and set my Leadins to 3/4" as is also recommended in the pm85 manual. However, on almost every cut, the torch comes down to cut height and immediately gets hung up on the pile of slag which has formed in the cut path. On far too many occasions, this has resulted in the destruction of $$$ worth of consumables including blown out Shields AND Retaining Caps! I've learned the hard way that the HT Duramax torch does NOT like to touch the material at all while cutting!

What I was wondering is: has anyone that uses Sheetcam ever tried the "wiggle" or "ramp" leadin option and if so how did you set the various other parameters (pierce delay, plunge rate, etc.)?

john

Not specifically related to sheetcam (which I do have) but I had made a mote to try the ramp leadin as from what I had read, it would be much kinder on consumables. Let me know what you find.

Weeell, I'm not sure that I'm volunteering to be the Guinea pig on that one. I suffered a catastrophic failure on my first time out of the gate trying to cut 3/4" on my brand spanking new PM85. (Cutting 3/4" steel was the main reason for choosing that machine.)

I had every thing set according to the HT manual and when I hit"go" I was met with an explosion of slag coming up at the shield/nozzle then a rooster tail of sparks coming out the back as the torch started to move forward. It shot up hard against the retaining cap, melting thorugh the shield then the Bakelite/fiberglass tube and after 30 seconds I was about $70 poorer.

Sorry If I'm over dramatizing my experience, but it is definitely NOT something I can afford to do on every cut.

The Ramp Leadin sounds promising, but there is absolutely zero information regarding its functionality in any of the Sheetcam docs, at least none that I can find. Based on what I know right now (nothing) I'm quite reluctant to try it for fear of another blow-up.

I'll be contacting the folks at Sheetcam for more info. If they respond favourably, I promise to share.
john

I'm also using a PM85 and also struggled with the issue. I used to keep a high pierce height and cutting height, which helped but wasn't the total answer. Now I use hyperthermcam for my posting and it has the option to do all the pierces first then it pauses, so you can clean the slag before resuming. Works good for me. I'm not sure if you can do that with Sheetcam. I agree it's no fun ruining a good set of consumables.