Arbor mock up for cupped grinding wheel

thingiverse

This is a design for an arbor to hold a cupped grinding wheel in my mill or lathe. It showcases how a 3D design can be printed to verify design dimensions. Avoid using a 3D printed arbor for grinding - even spinning - as it poses a serious risk. A rapid print of a design is useful for doing a test fit before operating a lathe, whether CNC or manual. Initially, I considered creating an R8 shaft, but I want to keep my options open for potential use with the lathe. Therefore, a 7/8" straight shaft is preferred, as it provides flexibility. The shaft diameter was designed at 7/8", which matches my largest R8 collet for my mill. This diameter also fits perfectly inside an ER-40 collet for the lathe. A print demonstrated a clearance issue approximately 33mm inside the R8 collet. To resolve this, I could shorten the shaft to 35mm instead of the original 70mm, saving both machining time and materials. Similarly, a test fit with the ER-40 collet suggests that the shaft should be less than 50mm to avoid excessive stickout. The initial 70mm shaft G-code was output to a lathe, where 1 1/2" steel was turned down to create a solid concentric arbor for the grinding wheel. Still, I need to finalize the shaft length and perform cutoff operations.