Rotary problems

(Dan Methvin) #1

I have a k40 machine with 3d board and running ligh burn on a rotary.
I created a file for a cup that had a space in the design so that it would do a 360 and print a logo on both sides of the cup.
When the cup was finished the 2 logos printed right beside each other.

I do not know why this is happening. I have everything set up correctly with the sizes and wheel size.
Any help would be great.

Thank you

(Dan Methvin) #2

Attached are photos

(Oz) #3

Was the item engraved in the direction shown on the preview, or did you rotate it 90 degrees for the rotary? And was it a roller rotary?

My best guess without seeing settings or your physical setup is that when the machine did the large rapid move between the two parts, the cup slipped on the rollers and didn’t move the distance it was supposed to.

(Dan Methvin) #4

I rotated the design 90. It is a roller hm v2 from Holga mods.

(Dan Methvin) #5

So how do I go about fixing this?
My settings were
30% power

Thank you

(Ray Kholodovsky) #6

I have seen the slip happen before.

You can set the maximum speed for the rotary (delta axis) by decreasing the maximum speed in the C3D Config File (assuming you are running the stock smoothie firmware) on this line:


The alternative is to physically put a weight inside the piece being engraved to keep it on the rollers.

These are still just guesses, we would need to see a full screenshot of your LightBurn Window (please, not a cell phone pic) and a video of the job running in order to be able to say more.

(Hank Morgan) #7

How about some rubber bands around the cup (or the rollers) to improve traction?

(Dan Methvin) #8

Ok I did it again. The wheels are not moving or slipping.

It has to be in the design or the software.

I can laser regular designs fine ie. single images or logos but with the design which is set to wrap 360 for a front and back logo at 1 time it does not recognize the space. There should be at least 50mm spacing in between

(Oz) #9

Do you hear a noise at the point where it should be moving? It could very well be that the stepper motor is being asked to either accelerate or move too quickly, which would make the stepper itself lose steps.

You could test this theory easily enough by just drawing a pair of small circles a good distance apart, and running the job without the laser enabled. See if it rotates properly on the rollers or if the motors make a strange whine instead.

(Ray Kholodovsky) #10

You should probably look into the configurations on the C3D board. Does the rotary manufacturer have guidance on the settings, motor currents to use?