I own an Omtech AF2028-80 CO2 Laser. I run the current version (2.0.05) of Lightburn Pro. I purchased the Omtech 4 wheel rotary tool. I’m getting mixed results - elongated images when I try to engrave an image. I’m wanting to understand the values that get entered into each of the fields in the Rotary Setup window and how the relate to one another. I select Roller, I select Enable Rotary. I enter the (drive) wheel diameter: 62mm. I enter the object diameter: 92 mm and the circumference is calculated. Now, the hard stuff: what value goes into the steps per rotation field? This field had the value of 10,000 before I started. I assume this value changes based on the circumference of the object being engraved - TRUE? There should be a straight forward formula with a ratio of the drive wheel circumference to the object circumference, but I can’t find it anywhere. Help please!
False. The steps per rotation never changes. It is the number of steps required to make the drive wheel rotate 1 complete revolution. The object size does not matter on a roller rotary because the wheels drive around the outside of the item. 10mm of travel on the wheel = 10mm travel on the item, etc.
The object size does matter when setting up your art in Lightburn though. The frame you use for placing your artwork must match the object circumference.
You need to determine what the correct steps setting is. The drive wheel should make one complete rotation when you press the test button in Lightburn. This video should help you understand how to set it up. It is using a Mansfield roller, but the process is the same for all roller rotaries.
Remember to power-cycle the machine so the controller uses the changed settings:
You may be able to poke the Reset button on the machine display, but AFAICT my controller sometimes doesn’t do a complete reset.
Please explain your statement: “The frame you use for placing your artwork must match the object circumference.”
Imagine the design on a sheet of paper the size of the Frame area (bounding box on the design when you select it). Now wrap that paper around the tumbler or cup. That is where the laser will burn.
This is mainly for full wraps, but also for alignment of items on oppesite sides.
In order for your design to fit exactly on the tumbler, the frame that you place it in must be the same size as the tumbler’s circumference. If it’s smaller than the tumbler, it won’t reach to the other side, if it’s larger than the tumbler it will overlap.
For example, here is a layout template for a skinny 20 that I use. The circumference is 235mm and the height is 205mm. For a full wrap I place the graphics exactly from one side to the other. I also have grid lines at the vertical quadrants and horizontal quadrants which I can use to align single graphics, or 2 graphics across from each other. These are set on a tool layer, I changed to normal layers for the screenshot so it’s more visible.
I can align graphics on thes lines and they will print exactly opposite from each other. If the template size doesn’t match the tumbler, the graphics will be off.
I have never done this and it works just fine.. Makes you wonder what the difference is.
With a wheeled rotary there is no change as it’s being driven by the wheels, not like an axes that it’s rotating around like a chuck object would.
So diameter isn’t involved as far as the rotary numbers are used.
What you get from Lightburn computing diameter is the numbers to make a tool bar around your image/vector.
Make sense?
Noob here; commenting for any and all tips on these; I’ve got the same model 80W and USB-0705, and am experiencing the same issues.
AI Overview Google recommended an older version of LightBurn; thoughts?
IMO, don’t depend on AI for detailed technical processes.
Start a new thread describing what happened after you followed the doc and the suggestions above. That’ll give a bunch of knowledgeable humans more information about exactly what’s happening in your machine and produce useful advice.