I purchased from Omtech an 80mm rotary axis attachment for my MOPA fiber laser but don’t know how to get the steps per rotation. I’ve asked Omtech but they told me to start with 3000 and then it’s trial and error. There has to be a better way! I’ve tried the following: 2000, 3000, 4000, 5000, 6000, 6500, 700, 8000, 9000, 10000, 11000, 132000. 12500 and the chuck just vibrates back and forth but never rotates. I need help.
This is the sad type of support you get from most of these companies… it’s too bad… it’s just bad customer service …
Try this thread… if your rotary is like mine for the fiber, it’s direct drive, so there is no ratio to adjust the step/rotation needed in the lightburn gui… This is for a co2, but there isn’t any difference…
I bought a Cloud Ray MOPA and they didn’t setup the rotary either. It was 12,800 steps/rotation…
If you have issues, sing out…
I don’t seem to find a placard anywhere and I’m scared to death to try opening the laser.
Your only option is to come up with steps/rotation. It’s usually in binary multiples…
You can see on my placarded motor driver how they increase. I would write OMTech back and ask them to give you an answer or allow you to open the case without voiding the warranty…
It’s either either crack the case or trail and error…
For the trail and error mode, use the test button in the rotary gui… it should rotate one turn and back.
Good luck…let us know what you come up with.
I guess it will be trial and error then. The fact that it doesn’t rotate at all no matter what step settings I use is concerning.
Okay so I started at 300 steps per rotation and increased it by 100 each time all the way up to13500 and it just vibrates back and force in super tiny movements. I am now frustrated and pissed because it doesn’t work. I have remained tech support but don’t expect to get an answer any time soon. 
Reduce the speed for that axis by a factor of 100, whereupon it should turn with ponderous dignity. Increase the speed by factors of two until it fails again, then back off by a factor of four.
Example: if it’s now set for 500 mm/s, set it to 5 mm/s and watch it crawl. Then creep upward: 10, 20, 50, 100, 200, like that. If it fails at 200 mm/s, then you set the speed to 50 mm/s and you’re done.
Then you can set the steps to get a single rotation.
Have you check to see if it’s wired correctly… with two phases it’s hard to think it could be miswired, usually they run backwards…
I’d contact the vendor again and advise them their suggestion doesn’t work. It’s possible you have bad hardware, but that’s unlikely. You bought this from OMTech, so I’d hold their feet to the fire on getting it working.
It’s pretty clear they have no idea about what hardware motor driver is in your machine.
If they can’t/won’t help you, you will have to look inside the case to determine the numbers. If the case has a warranty seal on it, I’d ask for them to allow access, breaking the seal and looking at the hardware… or they can have it back.
This is the only scenario that I can think of. You have to know the numbers… without the steps/rotation it’s totally a guessing game and we can’t be sure of the issue.
I’m sure it’s not what you signed up for… Sometimes they are a bit more responsive if you want to return it…since it doesn’t work like they said it would.
Good luck