The thin damascus cutoff wheels are a cheap, expedient, disposable item. I buy the unreinforced ones by the 100's, and go through them by the 100's. So they break. What does it matter? Put another one on and go at it again. Using these cutoff wheels is the very best reason to own a dremel tool. It's the thing that the dremel does that no other tool does as well.
You can get the thicker reinforced ones and they don't break, but they are thicker, cut slower because of that, and cost more.
Buy some of the thicker, reinforced, higher cost ones. Use them when appropriate, or use the cheap thin ones when they will work better. One thing I do with them is stack them on a mandrel to make varying thickness grinding wheels.
I use a dremel mandrel and the thin damascus wheels often in my mill or in my drill press with a x-y vise to cut hardened steel, or to slot it. They essentially never break when held steady in the mill, and can hold an incredible tolerance for straight cutting. Great for making custom screws, for slotting the heads. Or, for cleaning up buggered up screw heads so they can be removed.
I use these cutoff wheels for an incredible array of things. Cutting off allen wrenches to make refills for my hex bit sockets. Slotting hardened steel parts. Cutting off 18 ga finish gun nails that don't get fully driven. Recutting screw heads. Custom width grinding wheels. Slitting sheet metal items. Cutting ceramic or glass items.
