Anybody tried designing a rotary add on?

I have some spare steppers around, and I was thinking of trying to come up with a rotary style attachment (like you see for Chinese laser cutters). Just wondering if anybody else has started on that at all (no need to duplicate it if it exists elsewhere already).

If you’re talking about a 4th axis, we recently had a discussion about that here: I don’t think anyone here’s done it, but we did talk about some interesting possibilities.

Ahh yes, exactly what I was talking about.

I just printed a prototype that i probably won’t get a chance to hook up and test until next weekend.cost was under $25 total thanks to bobwomble’s 3 jaw scroll chuck on thingiverse. I really only built this for laser projects but I’ll experiment with it to see if anything can be done with wood if i can make it a bit stronger.


Thanks. this is just 15% infill for fit test but i intend to run it until it breaks:) kinda nervous about testing on wood.I’ll need to borrow some riot gear in case the work gets airborne!

Make sure you are wearing safety glasses, and have multiple video cameras running!

With that kind of gearing can it really go that fast?

“remember this: there is no more important safety rule than to wear these — safety glasses.”

This is an indexer and not a lathe so the precision and holding torque are preferred over speed.If you look at 4th axis add-ons on eBay or amazon you’ll see reduction gear boxes or similar belt and gear configurations. This doesn’t need to rotate any faster that your cnc can cut or laser etch material.

Assuming you have 3inch diameter stock. Circumference of material is 9.42inches and assuming you can cut at 60ipm means you only need about 6.37rpm on the rotation speed and I’m sure this design will exceed that considerably.

Right, I was commenting on your parts going flying comment. Pretty cool that we can print this kind of stuff, and it works. definitely moving the wife’s car out of the garage for this. I’m going to change a couple of things and reprint before i test. I’ll keep you all posted.

What could possibly go wrong?? :wink:

Update: won’t have time to test belt on the headstock was a bit loose, i made a mistake calculating distance between centers. Fixed that, reprinted at 30% infill which feels strong enough for sure. Also designed and printed a motorless tailstock with a chuck for extra insurance;) hopefully I’ll cut something In the next couple of days.

Any updates?

I miss that show.

Project delayed. The ramps board on my printer died so i borrowed one from the mpcnc .Replacement on the way.Als looking into how this will work on marlin set up. I know some simple firmware mods, like allowing cold extrude, will be required in order to use the extruder output for rotary axis but I’m hoping that’s all.

You should be able to just switch the rotary with the X or Y axis and call it a day. I’m more worried about the CAM side of it. I think fusion has a rotary option.

I know that wrapping the code should work with xory axis but since i don’t plan on adding an extruder i was wanting to dedicate that output to the rotary permanently so i dont Need to swap stepper connections. Aside from setting steps per mm and allowing cold extrude, can’t think of anything else getting in the way.

Have you made any progress? I’am really excited to see if the 4th axis can work on the extruder output and how that would be controlled.