Motor issue or...?

[Deezl Smoke]

2019 Arclight 6x12, Hypertherm 105, sheetcam, Commandcnc.
Lately this issue has been popping up on the first cut. It happens only on the left as you face the end of the table from the home position.

20211220_112715.jpg

So at my expense, I then have to re-cut and the second cut always turns out fine. Do I need a new motor on the X axis, or what are some possible causes of this?
Second cut.

20211220_113234.jpg

Thank you for any help.

[weldguy]

No, you do not need a motor. I suspect your gantry is driving into or over something. I would run that program with the plasma cutter turned OFF and closely watch as this happens to see if you can determine whats going on. Look closely at your rails and bearings while this is running and just keep running it over and over again until you see it. If you don't think its a mechanical issue after doing that please post your code.

[TJS]

How thick is that material. There is a large discussion over at the CandCNC forum. We as others have issue with torch diving and there are settings in the Config that are recommended. Not saying your torch is diving but mine does on 3/8" or thicker with my THC on. Cut direction looks to be counter clockwise (however I may be wrong from your lead in pic). I always thought the cut direction on outside cuts is supposed to be clockwise or something like that. However I am with Weldguy, something has some slop.

[Deezl Smoke]

No, you do not need a motor. I suspect your gantry is driving into or over something. I would run that program with the plasma cutter turned OFF and closely watch as this happens to see if you can determine whats going on. Look closely at your rails and bearings while this is running and just keep running it over and over again until you see it. If you don't think its a mechanical issue after doing that please post your code.

Great idea. I try to keep things as clean as I can given the place I have to operate the table. But there very well may be something like some pierce splatter etc. where it should'nt be. Thanks so much for the idea.

[Deezl Smoke]

How thick is that material. There is a large discussion over at the CandCNC forum. We as others have issue with torch diving and there are settings in the Config that are recommended. Not saying your torch is diving but mine does on 3/8" or thicker with my THC on. Cut direction looks to be counter clockwise (however I may be wrong from your lead in pic). I always thought the cut direction on outside cuts is supposed to be clockwise or something like that. However I am with Weldguy, something has some slop.

This material is .875" thick A36 mild. Yes, the cut direction is counterclockwise. The inside cuts are clockwise. I assume that is correct for my torch being a Hypertherm.
I had torch dive issues some time ago. I found deleting a reloading the toolset helped. Then I added several path rules like turning off dthc a few thousands before a corner sharper than 45 degrees, and turning it back on a few thou after the corner etc. Things like that really made the cuts nicer.

[weldguy]

Sounds like you have your cut direction backwards, check out this topic viewtopic.php?f=202&t=30272

Not that cut direction will have anything to do with the problem you originally posted about but it is important, particularly when cutting thicker materials to try and maintain a square cut with minimal bevel.

Curious to hear back about your original issue and if you found something loose or crap on a rail or something like that.

[Deezl Smoke]

Sounds like you have your cut direction backwards, check out this topic viewtopic.php?f=202&t=30272

Not that cut direction will have anything to do with the problem you originally posted about but it is important, particularly when cutting thicker materials to try and maintain a square cut with minimal bevel.

Curious to hear back about your original issue and if you found something loose or crap on a rail or something like that.

Yes, I see that now after TJS mentioned it, I looked it up on here with a Jim Colt thread. Now I have to work on that too. I have no clue how that got changed in the sheetcam.

Going to diagnose the table issue over Christmas. I have a feeling it may have some pierce splatter stuck in the gantry gear rack or something from before I bought the refrigerated air dryer. I had a bad series of slow piercing with a lot of splatter blowing upward into the Z mechanism. May have some stuck in the X rack. I will report back when I find it.

[TJS]

THere are some good posts on thick material to combat the volcano effect. I have to find it. I think it is something like a longer lead in and longer delay or moving while it is piercing. I cannot remember.

[acourtjester]

A simple way to find the location of the bump is to single step the G-code, no plasma. As you images show you may be always starting the table first cut at the same location and it only happens there.

[djreiswig]

I use a ramp pierce on thick material. Plunge speed same as cut speed. No pierce delay. Makes the slag shoot out behind the torch.

[TJS]

I use a ramp pierce on thick material. Plunge speed same as cut speed. No pierce delay. Makes the slag shoot out behind the torch.

Can you share how you do that.

[djreiswig]

Ramp pierce is an option in the sheetcam tool settings. I use a perpendicular lead in the same length as material thickness. Set plunge rate whatever your cut federate is and set pierce delay to 0.

[TJS]

Ramp pierce is an option in the sheetcam tool settings. I use a perpendicular lead in the same length as material thickness. Set plunge rate whatever your cut federate is and set pierce delay to 0.

Thanks. I never noticed it in Sheetcam. I will take a look.

[djreiswig]

edited_SheetCam-NoZ.png.jpg

[djreiswig]

I tried the wiggle, but it seemed to blow slag back up into the nozzle. Maybe it would work if you set it to wiggle more.

[Deezl Smoke]

Still working on finding the actual issue with my table, however I after inspecting for physical debris etc., and finding noting, I did wipe down that rail that I can not remember what it is called, but it is the one that you grease. After wiping them down and putting new grease on, I have not experienced this issue again.....yet. Always concerns me when I can't find the actual cause of an issue.

I have tried all available piercing options including wiggle. Wiggle pierce is a goofy one that one has to play with delay and height quite a bit. It can work if you have a thick plate job that maxes out your machine, but you can't edge start.
That said, I solved my pierce issues by buying a refrigerated air dryer. My desiccant system, no matter the size, just kept getting over run with moisture. So the refrigerated air dryer investment was made. Wish I would have done that when I bought the table. WOW what a game changer. Consumables don't really last any longer per'se, but pierce issues stopped, and cut quality went up. And.......now that I changed the direction of cut, which again I do not know how it got changed to start with, the quality of cut is back to like new. Thank you folks for pointing that out to me.

[weldguy]

Sounds like you did find the issue, debris on the rail, cleaned it off and all is well. Anything greased in a plasma cutting environment should be cleaned after each use. The plasma dust will stick to it and accumulate over time. I bet of you keep everything super clean you will not have that issue again.

Yes, dry air is a massive game changer that most people ignore, cures a myriad of issues for most folks. That's awesome, have fun!