There was a post I found talking about the exact same issue I’m currently having with my machine. I tried reaching out to the individual who posted it but she’s not receiving messages at this time. I was going to see if she ever found out what was causing it. She posted this example picture:
When I place out 30 patches on one sheet, some will cut evenly on both sides. But there are several that are off centered just as shown in the picture. I’ve had my machine for over a year and always allowed the machine to auto focus. But lately, I’ve been having issues. I’ve recalibrated my camera but when the crosshairs score out on the draft board they do not line up after focusing. Would this be an issue with my auto focus part? Does it need to be replaced?
Additional information is necessary to offer any assistance. Do you experience this problem every time and in the same place every time? Are you using a jig for your 30 patches? Were the designs placed using copy/paste. Does this happen with other designs?
The lid camera calibration does not change how or where the machine cuts, so that procedure is not going to help in this situation.
Yeah, there are not enough details to know what’s happening here.
Any cut that is lined up by eye with the camera view may be off by a little bit. The camera is not perfect and never will be. Even if some visually aligned work comes out perfectly that doesn’t mean that it all will. It’s not a problem with the machine, it is just how it is.
The only way to get perfectly aligned work every time is to use techniques that don’t require the camera to work.
If someone is doing things the right way and there is still an alignment problem, then things get interesting.
I secure a 12x20 leather sheet on the crumb tray and import a file into the Glowforge software. These are not individual patches already cut so there’s no template/jig needed. Once the designs have been engraved then they are cut. Some are evenly cut on both sides, others not so much. Sometimes I’ll just do a few designs at a time, maybe 3. 2 may cut just fine, 1 not so much. Sometimes all 3 won’t cut correctly. Sometimes all 3 may cut correctly. I guess it depends on what mood my Glowforge is in that particular day. Lol. She’s been extremely moody here lately. But that could be because I’m going through the process of changing out some wheels and belts because she started acting up and my lines weren’t straight. But the cutting unevenly started way before the other issue. I’ve got most of the wheels and belts replaced. It was literally a process of elimination to figure out what was causing the line issue. I just need to figure out what’s causing the uneven cutting.
But I don’t understand, I’ve had this machine for over a year and I never had this problem. It’s just recently started. I’m using the same files I used a year ago.
Yes and no. If I place the material in the center of the machine and set focus, most of the time I’m good. But not always. If I place it to either side, most of the time it’s off. Sometimes when I do full sheets, I set the focus directly in the middle, some will be good and others won’t. Random areas. It doesn’t make sense whatsoever. I thought maybe my auto focus could be going out. But I’m not sure, once it auto focuses in the beginning, does it stay at that setting for the duration of the job? Or does it auto focus through your the entire job?
I would think the auto focus would keep the setting throughout the job. I personally always use set focus on every job. One other thing as per your example above, is the cut and the engrave both created together or are you placing the cut onto the engrave by eyeballing it with the camera?
This sounds to me like you may have some build up or debris somewhere in the movement system that may be causing your alignment to drift slightly on longer jobs.
Have you ever gently cleaned the rails and wheels?
Are you using hold-down pins to secure the material?
I would make sure it cannot move in any direction and that the entire piece is completely flat down. I’m wondering if it’s slightly warped?
If the geometry shifts during the cut (i.e. pieces 3" apart are 3.3" apart etc) then you have a shift the computer is not accounting for. This happens if you move the head without turning the machine off. This also happens if anything else moves the head (or resists moving it) such as a slipping belt, or something in the way that the back-o-the-head fan exhaust hits, or something on the belt, or a bad roller that guides the belt.
If the slippage is horizontal then look at the head and gantry, if vertical it is almost always hitting something, otherwise the gantry will be crooked a lot.
