Rotary Help - Lightburn Interprets “Test” vs “Framing” differently

[Aspecht (Aaron)]

Hey there,

I have an Omtech 2028 - 80W laser that I’m trying to get working properly with their 4-wheel rotary axis. I thought I had it dialed in, but I went to make a coffee tumbler tonight, now the images were getting skewed. I’ve done a fair amount of testing and finally, I decided to call it quits and ask for more help.

Currently, the situation is this, I have my steps per rotation set to 3920 and the roller diameter set to 70mm. This allows for a near-perfect rotation when using the test button in the Rotary Setup menu.

(ignore the error message, I’m designing on one machine and running on another at the moment)

Now the issues start here. When I go to frame my artwork, even though the height and circumference are the same, it travels beyond 1 rotation. When I tried making a 3.5in x 5in rectangle, it ended up being 4.5in x 5in instead. What could be happening that the test and frame options are so out of whack?

Does anyone have any thoughts on what’s going on here?

[thelmuth (Tim Helmuth)]

Where did you get those settings? Is 70mm the actual diameter of the wheel? That seems a bit large to me for a 4 wheel.

[Aspecht (Aaron)]

Straight from the omtech website. Measuring with a ruler it looks very close.

[thelmuth (Tim Helmuth)]

OK, just confirming that the wheel makes one complete revolutiion and back with the test button.

[jkwilborn (Jack Wilborn)]

@Aspecht

I have my steps per rotation set to 3920

Where did you get the 3920 value?

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Do you know the motor to drive wheel ratio?

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Here is a very simple setup for a rotary… see if it helps you out.

A rotary attachment question. Warning: Newb

Configuring for a rotary should not be an issue. I’m assuming you are using the Y axes… you didn’t say… find steps/rotation a. identify the switch settings b. translate from the motor driver placard steps/rotation is then computed based on a ratio. a. value entered is steps/rotation multiplied by the ratio which results in the steps/rotation of the wheel, which is what Lightburn needs to know. This is the basic procedure. [motor-driver-switches] Look up the settings on the devices pla…

Let us know if you have difficulties and we can look closer.

[Aspecht (Aaron)]

Y’all, I’m just a dummy. I didn’t fully read the Lightburn setup documentation. I was rotating my tumbler a full rotation, not the wheel!! That’s what I get for trusting some rando on YouTube!

[thelmuth (Tim Helmuth)]

Glad you got it sorted out.