Summary

A protective cover for thin Dremel and similar cut-off grinding wheels.

Update
I did a remix http://www.thingiverse.com/thing:1010900

Update 9-15
Another remix. This one has a screw-on cap.
It's probably finished but is marked a "Work in Progress" http://www.thingiverse.com/thing:1036486

Instructions

Dremel cut-off wheels are fragile. Without protection they tend to get broken.

I break more of these wheels when they are sitting idle than I do while working with them. So I made this protective cover several months ago and, so far, so good. I just toss it in the box with the rest of the tool bits.

Tried different cover configurations, like slipping it on sideways, but this seems best. There's less chance of accidentally snapping the disk when applying or removing the cover.

It fits a 0.175 inch (4.45mm) diameter (upper-shank) mandrel. This mandrel might be a cheap knock-off or a genuine Dremel part, but I'm not sure where I got it.

Whatever the case, the mandrel should be a smooth, gentle snap-fit into the hole. The design had zero-clearance and, thanks to plastic shrinkage, the fit was perfect. Slight scaling up or down may be required for other mandrel diameters.

It's a small print so recommend printing with thin layers, slow speed plus fan cooling for the best dimensional accuracy.

24 minutes, 4 grams ABS on an Afinia.

Metric file included.

Dremel wheel protector