Peter Lowe
03-30-2014, 10:08 PM
Hi everyone,
I am trying to get an Epilog cutting optimally for a project I'm working on and and am having some issues with the kerf width. It is a 60W helix from 2008, and I am hoping to get its kerf while cutting MDF very similar to that of a 40W helix from the early 2000's that I have used.
The kerf is fairly thin when the machine cuts at the lower right corner, but is quite noticeably wider at the upper left (closest to where the beam enters the table), and leaves a rounded charred edge on both sides of the cut.
Top left cut: https://www.dropbox.com/s/032ai62xww00e71/top%20left%20cutting.JPG
Bottom right cut: https://www.dropbox.com/s/h914vq9i8z17jf2/bottom%20right%20cutting.JPG
Examining the pattern of the red dot pointer on a piece of paper attached to the cutting head while moving it around gave me a theory about the problem. The pointer is fairly focused at the head when it is at the upper left of the table, and grows noticably as the head is moved toward the lower left, with two small red points migrating completely away from the cutting mirror (and so not going into the lens).
Top left pointer: https://www.dropbox.com/s/nmvk798aw0ixv72/top%20left%20pointer.JPG
Head slid 1/2 to right: https://www.dropbox.com/s/0ayzrgf6mtvsh5t/top%20left%20pointer%20slid%20.5%20right.JPG
Head slid fully to right: https://www.dropbox.com/s/6rlgiet6srobbi2/top%20left%20pointer%20slid%20full%20right.JPG
Bottom right pointer: https://www.dropbox.com/s/66rwpqw5mxljylb/bottom%20right%20pointer.JPG
I am thinking that if the cutting beam follows this same pattern (with the assumption that imperfections in the red dot pointer are due to the path through the machine, not the pointer itself), then some of the poorly collimated light escapes completely from the cutting path and doesn't end up increasing the spot size.
Additionally, the light that is poorly collimated, but not badly enough to completely escape gets focused tighter by striking the lens closer to its edge (the beam effectively being expanded by the increased distance to the cutting head).
My whiteboard sketch of wider beam having smaller spot size: https://www.dropbox.com/s/3zg3hnpzq071z9r/Cutting_theory.JPG
I have cleaned all the mirrors and the lens (and replaced the mirror in the cutting head), aligned the beam per the published procedure, and am trying to decide what to try next.
There are a few small spots on the mirrors that I did not replace and my only remaining thought is to replace them and see if that fixes the problem.
Does anyone else have thoughts?
I would also like to improve the bottom right performance if possible, as it is much better than the upper left but still noticeably wider than the 40W machine's cut.
Thanks!
Peter
I am trying to get an Epilog cutting optimally for a project I'm working on and and am having some issues with the kerf width. It is a 60W helix from 2008, and I am hoping to get its kerf while cutting MDF very similar to that of a 40W helix from the early 2000's that I have used.
The kerf is fairly thin when the machine cuts at the lower right corner, but is quite noticeably wider at the upper left (closest to where the beam enters the table), and leaves a rounded charred edge on both sides of the cut.
Top left cut: https://www.dropbox.com/s/032ai62xww00e71/top%20left%20cutting.JPG
Bottom right cut: https://www.dropbox.com/s/h914vq9i8z17jf2/bottom%20right%20cutting.JPG
Examining the pattern of the red dot pointer on a piece of paper attached to the cutting head while moving it around gave me a theory about the problem. The pointer is fairly focused at the head when it is at the upper left of the table, and grows noticably as the head is moved toward the lower left, with two small red points migrating completely away from the cutting mirror (and so not going into the lens).
Top left pointer: https://www.dropbox.com/s/nmvk798aw0ixv72/top%20left%20pointer.JPG
Head slid 1/2 to right: https://www.dropbox.com/s/0ayzrgf6mtvsh5t/top%20left%20pointer%20slid%20.5%20right.JPG
Head slid fully to right: https://www.dropbox.com/s/6rlgiet6srobbi2/top%20left%20pointer%20slid%20full%20right.JPG
Bottom right pointer: https://www.dropbox.com/s/66rwpqw5mxljylb/bottom%20right%20pointer.JPG
I am thinking that if the cutting beam follows this same pattern (with the assumption that imperfections in the red dot pointer are due to the path through the machine, not the pointer itself), then some of the poorly collimated light escapes completely from the cutting path and doesn't end up increasing the spot size.
Additionally, the light that is poorly collimated, but not badly enough to completely escape gets focused tighter by striking the lens closer to its edge (the beam effectively being expanded by the increased distance to the cutting head).
My whiteboard sketch of wider beam having smaller spot size: https://www.dropbox.com/s/3zg3hnpzq071z9r/Cutting_theory.JPG
I have cleaned all the mirrors and the lens (and replaced the mirror in the cutting head), aligned the beam per the published procedure, and am trying to decide what to try next.
There are a few small spots on the mirrors that I did not replace and my only remaining thought is to replace them and see if that fixes the problem.
Does anyone else have thoughts?
I would also like to improve the bottom right performance if possible, as it is much better than the upper left but still noticeably wider than the 40W machine's cut.
Thanks!
Peter