blow holes in plasma cutting
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- Posts: 3
- Joined: Tue Feb 10, 2015 3:01 am
blow holes in plasma cutting
I am trying to plasma cut some art work. I want to cut just a single line (like to highlight a feather on an eagle drawing).
When I cut the line I get a blow hole when the torch first starts. I have tried various combinations of settings, but without success. Could anyone suggest how to set up for this cut. I have a LDR Motion Systems table, Hypertherm 65, SheetCAM and Mach3 software.
Thanks for any help
Robert Grams
72686 331 Ave
Imperial, NE 69033
308-882-4084 home
308-883-8000 cell
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When I cut the line I get a blow hole when the torch first starts. I have tried various combinations of settings, but without success. Could anyone suggest how to set up for this cut. I have a LDR Motion Systems table, Hypertherm 65, SheetCAM and Mach3 software.
Thanks for any help
Robert Grams
72686 331 Ave
Imperial, NE 69033
308-882-4084 home
308-883-8000 cell
This email has been checked for viruses by Avast antivirus software.
www.avast.com
- Les Newell
- Site Admin
- Posts: 3665
- Joined: Thu May 11, 2006 8:12 pm
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- Posts: 3
- Joined: Tue Feb 10, 2015 3:01 am
Les
When you say a very short pierce, I assume you mean a short pierce delay. If that is the case I am already using "zero" for pierce delay. What else can I do here?
What do you mean when you say to "use a cutting rule to slow down the beginning of the cut"? And how do you do this.
Thanks again for your prompt reply.
Tumbleweed
When you say a very short pierce, I assume you mean a short pierce delay. If that is the case I am already using "zero" for pierce delay. What else can I do here?
What do you mean when you say to "use a cutting rule to slow down the beginning of the cut"? And how do you do this.
Thanks again for your prompt reply.
Tumbleweed
I'm trying to do pretty much the same thing, plasma does have drawbacks, one of them being that the pierce is always bigger than the cutting kerf.
I think Les is hinting at slowing down the start of the cut so it makes the kerf wider - the torch is moving too slow for a normal cut so it burns away the metal from either side.
I have not tried this myself yet but it sounds possible, maybe.
I try to keep the flow for open cut lines to start at the same end so all the pierce holes are the same, or try to build them into the design.
There may be other ideas but I know exactly what you mean and it's a pain.
I think Les is hinting at slowing down the start of the cut so it makes the kerf wider - the torch is moving too slow for a normal cut so it burns away the metal from either side.
I have not tried this myself yet but it sounds possible, maybe.
I try to keep the flow for open cut lines to start at the same end so all the pierce holes are the same, or try to build them into the design.
There may be other ideas but I know exactly what you mean and it's a pain.
- Les Newell
- Site Admin
- Posts: 3665
- Joined: Thu May 11, 2006 8:12 pm
I was playing with this morning, tried deliberately slow cutting, pierce was on zero anyway. There seems no way out of the hole, I was getting a 0.85 kerf but the pierce was maybe 1.6mm or more, it's pretty noticeable.
I guess if I was really worried I could flash the holes with Mig or Tig but hopefully won't need it.
I will try the low pierce height and see if that makes a difference .
I guess if I was really worried I could flash the holes with Mig or Tig but hopefully won't need it.
I will try the low pierce height and see if that makes a difference .
Could also modify the artwork to have a point at one end of the line, use the torch as a drill on the point then start the cut at the opposite end and cut towards the "drill" hole?
The POST option sounds good too but a better refinement would be to have a check-box in the tool list for "Pierce at both ends" but I guess that's leaning towards a custom program modification?
The POST option sounds good too but a better refinement would be to have a check-box in the tool list for "Pierce at both ends" but I guess that's leaning towards a custom program modification?
The check-box would be nice.
If it could be incorporated, should the check-box be available in the Operation instead. I could see a layer for these "both end pierce" or "Pause at end of cut" and then other layer(s) for profile, etc. using the same "tool". The option in the Operation may be more intuitive (at least in my mind).
Paul
If it could be incorporated, should the check-box be available in the Operation instead. I could see a layer for these "both end pierce" or "Pause at end of cut" and then other layer(s) for profile, etc. using the same "tool". The option in the Operation may be more intuitive (at least in my mind).
Paul
- Les Newell
- Site Admin
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To make the end delay work the other way around it only takes a small tweak to the post. Edit your post and look for function OnPenUp(). Depending on the exact post the code may vary a bit but you'll probably have spomething similar to this:
Change it to:
Code: Select all
post.Text (" M05\n")
if (endDelay > 0) then
post.Text (" G04 P")
post.Number (endDelay,"0.###")
post.Eol()
end
Code: Select all
if (endDelay > 0) then
post.Text (" G04 P")
post.Number (endDelay,"0.###")
post.Eol()
end
post.Text (" M05\n")