Do you find that the speed is too fast? Seems like between that and the low thermal mass of the platters you'd have problems with heat control and maintaining temper on the tool.
The ones in this pictures are made better looking in wooden boxes, etc... but i have one that i use regularly to sharpen my precision cutting tools and it's a hard working horse for many years! Only a 7.200Rpm HDD drive powered by bench top PSU 12Vdc plus +5V regulated from 7805 attached to the drive.
Do you find that the speed is too fast? Seems like between that and the low thermal mass of the platters you'd have problems with heat control and maintaining temper on the tool.