I am trying to set up my rotary on a HaoTian UV Galvo and the steps per rotation should be 48000 which also match the test in lighburn (y-axis) as it rotates exactly 360 degrees. However when I do a test line at 100mm it only engraves 93mm. In order to engrave 100mm I need 52200 steps per rotations, but at that number the lightburn test 360 rotation is way off.
I have no idea what could be causing this discrepancy. I have randomly played around with other settings, but always get 93mm.
Might want to advise us of the version of Lightburn you’re using.
Mine is configured to 12,800 if I remember correctly. This corresponds to whatever steps the motor driver is configured.
The test button in the Lightburn gui should cause it to rotate one complete rotation and back. If it’s doing this, then the issue is likely elsewhere.
Using a chuck rotary, if you object diameter measurement is off, so will the results.
If the test button works, you’ll have to hang around until someone else joins us, as far as I can tell it’s working.
Sounds like your scale is off. Do you get exactly 100mm on the flat? What are your rotary settings? Another great test is make a shape exactly = to the circumference and see if it closes. First minute of this video is a good example of closing a full wrap,
Using lightburn 2.0.02
I am setting up a piburn galvo chuck rotary. This should be 12,800 x 3.75 = 48000.
I have triple checked the object diameter and it is 89
I still get a 93mm line when trying to engrave 100mm, however going exactly with the circumference of 279.46 it does close the shape.
I did also test a 20 x 20mm and it is only on the y-axis there is a problem, where it comes out at 18mm. The x-axis is correct at 20mm.
Everything is perfect on the flat.
So that may seem strange at first, but, in the “Closing the shape” test the software calculates the length of engraving to equal 360 degrees, so regardless of actual circumference, IF the object on the screen equals the dimension that is input into the field, the rotary will turn 360 degrees. (If steps per rotation are correct). Next test would be wrap a string around the wrap and measure.
Question:
Is your workpiece tapered?
Really stupid question, did you set your caliper to zero before you measured the diameter?
Are you sure you didn’t transpose a couple numbers when you entered the diameter?
89mm diameter = 279.60 circumference
I did actually use 279.60 on my engraving computer, but when I used the other computer for these posts, I typed it in wrong.
I have used this whiskey glass for years on my co2 laser roller rotary and I know the diameter of 89mm is correct, however that was also my downfall, as it actually does have a little bit of a taper that I have never had to worry about, so it didn’t cross my mind.
Appreciate your help as that did fix the issue.