Engraving powder paint tumbler problem

Hello, thanks for your feedback.
I changed it to .001 in and improved a bit.
No, the lines are not part of the design.
Even with the set of .001 in and the rotary accessory it keeps leaving some paint lines in the engrave.

What stepper motor is your rotary using and what type of belt pulleys?

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I looked for motor information but nothing attached to it.

Usually the stepper motor will have a part number somewhere on it, and that can almost always be decoded. It’s usually on the back.

It could be that this is simply rotating further than it should for each step due to the choice of stepper motor and gear ratio on the pulleys.

Engrave two lines a substantial distance apart (say 50 mm) and then measure the distance between them with a flexible tape wrapped around the object. If it’s longer than it should be, then that’s where your problem is.

From zooming in on your picture earlier, it looks like a GT2 belt with a 20 tooth drive pulley on the stepper and a larger — but I don’t know how much larger — pulley on each rotary wheel:

It also looks like it’s at least partially a 3d printed kit. Share with us all the information you have on your rotary kit. Don’t hold back and make us guess.

With regard to:

This is where not having an analog ammeter might have hurt you; it might be that your tube is damaged from over-driving it (very easy to do without an analog ammeter) and just doesn’t have enough power for that paint. Alternatively it might be poor focus, thus the ramp test.

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hey, @Daniel_Juarez did you manage to fix the problem?
I’m having the same issue and pulling my hair out!@

Hey
What problem are you referring to? I had several
I will be glad to help

hey,
The lines in your design while raster engraving

If you’re already using a scanline step of 0.001", you could replace the (presumably) 1.8° stepper motor with a 0.9° one or add some gear reduction if it’s a DIY rotary.

If you replace the M2 Nano with another controller, you could change the micro stepping.

And there is also the option to defocus the beam a bit, but I’m not sure if a K40 has enough power for that. You need more power if you want to remove paint with a wider less focused beam.

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Hello

Yes, reduce the scan line to the minimum 0.001

I had to rebuild(bearing replacement) a motor on my K40 and was told the stock motors were 0.9° motors. So I would think a rotary made for the K40 would have a 0.9° also since it’s expected to swap it in as the Y axis. Odd it’s still doing it at 0.001 scan setting.

Has me wondering if rotating the scan to 45° would change the effect for the better.

K40 Whisperer got a scale factor for the rotary (you can also reduce the speed for travel moves). So, you can use a motor with a different step angle or some gear reduction. The steps per inch don’t need to be a 1:1 match.

You could do that kind of thing with a chuck type rotary, but a rim drive doesn’t have a firm grip on the item. The item usually wanders a tiny bit. If you go line by line, being off by half a mm at the end of a quarter turn won’t be noticeable. However, having that kind of error from one scanline to the next would likely result in visible defects.

With a rim drive, I’d definitely try to keep the rotation moves to a minimum.

Well, I’d do the same with a chuck rotary since it’s a slow axis. Heh.

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Good points but I would hope things are setup so there is no slipping at all. Good to have a plan for if there is slipping but in this case/problem I would slow things down so there’s no chance of slipping.

To experiment and not waste product, maybe testing things on a paper towel roll or something else you are ok with disposing of and doesn’t cost much/anything.

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