June 16, 2026
Description
This is a housing set used to create a 6 inch (150mm) rotary slow speed grinder for faceting, flattening, or sharpening Very Hard materials.
The motor used for the project is a 24v DC geared motor that is setup to run ~200RPM from a cheap “wall wart” power supply. This is fast enough to perform good work without being fast enough to create lots of heat or slinging swarf too forcefully. I chose a small cheap motor because if I stall the motor, I was using too much pressure. Very hard materials can be brittle and become damaged easily when subjected to significant heat or pressure.
https://www.amazon.com/gp/product/B08D3SXJ5H
https://www.amazon.com/Universal-Converter-100-240V-Transformer-Switching/dp/B0FQK3ZZLW
The flat abrasive discs and aluminum platen were purchased from Aliexpress; I chose a seller that had all of the grits I wanted and bought them all at once just to simplify things.
https://www.aliexpress.us/w/wholesale-150mm-diamond-flat-diamond-disc.html
It is my belief that this system would work nicely in several additional configurations…
Cabbing Platen
Wool, foam, and/or leather covering for lots of rounding
Soft Sanding Platen
Hook and loop for off-the-shelf sander discs for mild rounding
Hard Sanding Platen
Sticky back sandpaper for very little rounding
Optical Pitch Platen (if the bearings in the motor were good enough, they are NOT)
Powdered abrasive on platen with thick pitch coating
Would require a bruiser plate to create/maintain flatness
Printed mine from Cheap PETG to ensure any heat or pressure doesent't deform it too much. Even with default printing profile the base with the slots took FOREVER!!! lol
License:
Creative Commons — Attribution — Noncommercial — Share Alike
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