I am toying with the idea of building a benchtop lathe around a Taig 5C headstock, with a direct drive motor. Frameless motor components are available relatively inexpensively now from AliExpress and some other suppliers, and could make a very clean, compact machine. The spindle tube on the Taig headstock is 42mm diameter, so everything needs an ID larger than that. The best component choices I've found so far are:
Motor: RI85 model 2Nm rated, 5Nm peak, 48V 16A $178 https://www.robotshop.com/products/cubemars-bldc-motor-with-potting-robot-arm Encoder: 46mm bore 40kppr $71 https://www.aliexpress.us/item/2255800909154622.html I want to be able to do C-axis positioning for mill-turn work, so want decent resolution. The AliExpress listings for encoders leave a lot to be desired for both mechanical and electrical specs. For example, I have no idea what the maximum frequency is for this 40k pulse (counts?) per rev encoder. The motor is rated for 3100 RPM, and I'd like to be able to go that fast. That would be over 2MHz. I plan on designing a brake to lock the drawtube and use the motor to open and close the 5C collet. I may make a dinky bar feeder for it. Questions: - Anybody used one of these frameless motors? Anything to watch out for? - Any cheaper encoder options out there that would work well? Will this type of magnetic encoder work for a 3krpm spindle? - Any other ideas or suggestions? Thanks, -- Ralph _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
