Laser Rotary Axis

Last crawled date: 4 years, 1 month ago

This is a fully functional low profile wheel-style rotary axis for Laser Engravers/Cutters. There are a few purchased parts, but most of the interesting stuff is 3D printed.
The motor is a standard NEMA17, I plug-replace my Y-Axis motor with this one (only do this with power OFF!). The idlers are fully adjustable for position along the rail, and for height on its support bracket. Thumb locks are provided, all nuts are captive.
Also included is a double-tire wheel (optional) for use on either or both ends. This works great with the narrow foot of a typical wine glass.
The Drive Wheel Plug (two per wheel) replaces the bearings on the wheels at the motor end, allows it to be clamped and driven by the M5x50mm screws that have the pulleys on them. Tighten the M5 nylon locknut to secure in place. See cutaway view. Also notice the 1mm thick precision shims, these are used throughout to mate things like pulleys and wheels to the respective bearings so that they don't rub on the periphery.
See exploded assembly view for full details. WHEN ASSEMBLING, DON'T FORGET TO INSERT THE 6MM SPACER BETWEEN THE BEARINGS IN THE MOTOR MOUNT!
I use LightBurn to drive this, but RDWorks is also OK.
Parts to be bought are listed below. CAD models available on request.
Comments are welcome, I expect to improve and update this as I use it more.
Suggestion: Turn off "Homing" on your laser to avoid running into the idler bracket. Also, I use "Current Position" in Lightburn to avoid unnecessary movement.
Note: I have flipped the orientation of the M5x50mm screw in the cutaway illustration to better match how I actually assemble it. Either way will work, but it's a bit easier to mount the pulley etc. as shown.
Here is a video that shows a couple of 20 oz powder coated tumblers that I etched on my 100w machine, the results are quite good.
https://youtu.be/nCclw3OKcxs
Here's a video of the actual etching process, with a bit of cleanup.
https://youtu.be/B2u9_wLRUNU
BTW I used water-based ("Household") Goof-Off to clean after etching. I learned the hard way that when cleaning powder coated material to avoid the "Full Strength" Goof-Off, it will dissolve the paint.
I'm still dialing it in -- the job in the second video is at 250mm/sec at 30% power (instead of 150mm/sec 30%). The etching worked fine and the stainless is cleaner and shinier with less cleaning.
Many thanks to Openbuilds for their great components that make this design possible!
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Purchasable parts:

NEMA 17 motor, 2-phase. Any make.


Rubber O-Rings, M3.5x16 Buna-N 70A durometer. The ones I bought are from Amazon (package of 25): https://www.amazon.com/gp/product/B00NJTWYO4/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1


M5 x 50mm low profile screws. Available from OpenBuilds.com
M5 x 8mm low profile screws. Available from OpenBuilds.com
M5 x 25mm low profile screws. Available from OpenBuilds.com
M5 x 30mm low profile screws. Available from OpenBuilds.com


V-Slot linear rail, 20x60mm. Available from OpenBuilds.com


Delrin V Wheel Kit. I wrap the O-Ring around this, in the groove. Available from OpenBuilds.com


Tee-Nuts, 5mm for 20mm rail. Available from OpenBuilds.com


2GT-2mm Pulleys, 20T, 5mm bore for 6mm belt. Available variously from Ebay etc.


2GT-2mm Belt, 80Teeth, 160mm long continuous, 6mm wide. Available from Amazon:https://www.amazon.com/gp/product/B014QLGXYK/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1


(optional) Aviation plug connectors, available from Amazon: https://www.amazon.com/gp/product/B07D7SHKGK/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1


M3x7 (or M3x8) cap screws to mount motor. Two required.


6mm Spacers, these go between the bearings on the Motor Mount. Available from OpenBuilds.com


Ball bearing: 625 2RS 5x16x5, four required (in Motor Mount). Available from OpenBuilds.com. These are included in the V-Wheel kit.


Nylon Insert Hex Locknut - M5. Available from OpenBuilds.com

Precision Shim - 8mm OD, 5mm ID, 1mm thick. Can use 10mm OD. Available from Openbuilds.com
The powder coated 20 oz stainless tumblers were purchased from Amazon. These generics look great and are much less expensive than the name-brand (Yeti), time will tell if they are as good:
https://www.amazon.com/gp/product/B07VXQ83R9/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1