I recently bought a Harbor Freight 6" double carbide grinder:
.I then mounted a Norton aluminum oxide wheel on it. This was the first drama. Although both are nominally 6", the HF wheels are slightly under, and the Norton is slightly over, and didn't fit, hitting the inside of the guard. After a few hours of work with an air die grinder, it now fits.
Trued the wheel up, and fixed the water drip (shorten pipe, make gasket thicker so valve arm points in the right direction.
Ground a piece of 5/16 by 3" MoMax bar to be a flycutter bit.
Used it in the Millrite to face off a piece of hot-rolled steel I've used as an anvil for ~40 years, using black sulfur oil as the lubricant. The block is 2" by 4" by 9". Machined one of the 2x4 faces flat, and chamfered the 4 edges with a 45-degree "saw" (really goes in a horizontal mill).
Generated lots of smoking curly little chips. Haven't tried for blue yet.
Joe Gwinn