The lower image is engraved with line only. The top one is the identical image using line+fill. The image was traced in lightburn and only flipped so the text would be readable.
Oz or Blake any ideas?
Does this only happen on the rotary, or on flat surfaces as well? There are two things I know of that can cause this:
- The item is wandering on the rotary as it spins (would only affect rotary)
- The step pulse polarity is set incorrectly (would affect all scanned jobs, but nearly invisible for cuts)
The rotary has a pressure finger and is not slipping. The line cuts perfectly.
Happens only on the rotary.
Where do find the setting for step pulse polarity
If it doesn’t happen when you aren’t using the rotary, it’s not the step pulse polarity - that would affect any scanned job.
What does it look like when you preview?
Preview is fine…hmmmm…
Is the outline following that same slanted line? This is very strange. We have lots of users with Ruida hardware using rotaries, and I’ve never seen this before.
Yes it is…the top one is line +fill…weird.
Try this for me? Save the file as an RD file, then import it again, and post a screen shot of that. That should show if the actual output from LightBurn is being created properly.
Ok and thanks…give me a few.
Let me disconnect the rotary and print this engrave this file again. Its been a week or so since I cut this without the rotary and maybe the polarity is wrong.
The motor driver being on its way out can do that too.
The polarity thing works like this: The controller sends a pulse every time it wants the motor to take a step. A pulse is “on, then off again” or it can be “off, then on again”. These are called ‘trailing edge’ or ‘rising edge’ respectively, and the motor controller and laser controller have to agree on which one is used. If they’re set different, then what happens is the controller ends up changing direction in the middle of a pulse instead of after it, so you miss exactly one step at the end of each scanned line.
If you set the scan interval smaller (or the DPI higher), it slants more, because you miss more steps in the same amount of space, so this is a way to test if that’s it: set the interval smaller or the DPI higher and try it again. If the angle of the slant increases, that’s probably the issue.
You mentioned on another thread that you recently reset your controller back to factory settings? If you haven’t run a scan since then, that could absolutely be what happened.
Off the rotary if engraved fine…
Does your rotary have its own motor driver, or does it use the one for the Y axis? How do you have it set up?
It has a separate motor controller but it’s own motor.
Separate controller might be the key - If that motor controller is ‘trailing edge’ and the one in your laser is ‘rising edge’ that could easily be the difference. Is it the exact same motor controller as used on your laser’s Y axis, or did you just get ‘something’ ?
It is different from the ones that came with the machine.
Dip switches would have had to be changed each time I wanted to switch and this is a nema 17 on the rotary.
Do you think that controller is bad?
I’m trying to work through it in my head - When using a rotary, the X goes back & forth, and the Y steps “once” per scan (usually a few steps, but shouldn’t be relevant). If the X axis driver is set to the wrong pulse type, you miss an X step with each direction change. In your case though, the Y axis isn’t changing direction, so at worst you should only be off by one motor step, which wouldn’t be visible.
Having said that, since it only goes wrong when the rotary is connected, it seems like the most likely culprit. Is the bottom design you showed on the cup just running a generic cut, but using that rotary motor, or did you just use the machine normally for that?
I guess my other question is, just making sure, you’re using the Y axis for the rotary, correct? Like, the cup lays sideways and you’re scanning the laser head left to right, with the cup rolling toward or away from you, not left to right?