We have an Omtech Pro 3655H
Trocen controller
Firmware is 2.24.12.3
Using Lightburn Pro 2.0.04, I made a design for a rubber stamp.
In lighburn the cut shape lines up with the fill shape, but when we send it to the laser it displays as being offset, and when the laser does the cuts it does cut the way it shows in the display on the Omtech laser and not how it looks in lightburn. We have a Trocen controller, not ruida.
If you zoom in on that second pic you can see the outline of the cut is not centered on the red fill.
This happens when I create the cut line with the rectangle tool in lightburn or by creating an offset shape.
If I turn on “bi directional fill” then the offset goes away, however, then the text in the middle, which is kinda the point of the whole thing, is all messed up. You can see that in the pic below.
I noticed the problem only when I added the line cut.
I was doing an series of incremental tests on a sheet or rubber to see what settings we needed to do to make the stamp a nice depth. When I got what I thought was a good depth of cut, I added the line cut to cut it out so we could try it out. Previously I’d just cut them out with an x-acto.
If I have it cut and engrave now, it either engraves the stamp perfectly but cuts the stamp wrong, because of the offset, or the cut is good but the stamp itself gets all messed up from the bi-directional fill. I am unable to get a good photo of the messed up ness on my phone, but it makes a kind of duplication or ghost where we get two images. This ghosting goes away as soon as we turn bi directional fill off, so I don’t think it is caused by mirror misalignment or a dirty lens.
I couldn’t get a good picture of the name stamp. Kept being too blurry or too hard to see what was going on, so I used a drawing of a snail one of the kids wanted to make into a stamp.
The right snail is without bi-directional fill.
The left snail is with bi-directional fill turned on.
@soniclab: This looks ominously like a recent unresolved problem with a different controller:
The two problems are similar enough to suggest something is awry with how LightBurn is now doing things, not with the machines or their settings. The offsets are too large for Offset Fill Adjustment and apparently not mechanical.
Scanning offsets are not applied when previewing in LightBurn, only when sent to the laser, and will affect the preview there.
When using bidirectional, the offsets are applied in both directions, and when using unidirectional they’re only applied to one side.
In other words, your preview looks exactly as it’s supposed to, but your scanning offsets are likely incorrect. They should not be nearly that large.
I noticed that you have your edit window in inches. One thing that I’ve seen often is that companies often supply scanning offset values with machines, in millimeters, and then users enter them in inches, effectively making them 25.4x larger than they should be.
There’s even a warning in the box you use to enter the values:
I wasn’t able to work on it over the weekend, but i spoke to one of the people here that did, and here what they did that worked:
remove the device from Lightburn, close Lightburn, open it back up and reinstall the device. That got rid of all the various settings that folks did, who knows what someone fat-fingered in there incorrectly.
Printed out 50x10mm rectangles at various speeds, 50mm/s through 900mm/s, measured the offset, divided it in two, and set that in the device settings. Repeat until the offset was unmeasurable.
It now seems to be cutting and engraving correctly, uni-directionally or bi-directionally.
