Review on 🪚 Dremel 420 Cut-off Wheel, 15/16", 0.40” Disc Thickness - Rotary Tool Accessory (20 Pieces) by Scott Kulothungan

My standard is Dremel 409 cut-off wheels which are .025" thick so they tend to be brittle and break. So I tried 420 .040 inch thick. and significantly thicker. Although the kerf is stronger, it is thicker and because it is an abrasive cut, much more debris remains from the cut and the heat generated is higher. I mostly cut metal with it and eventually went back to the thinner 409. I also felt that the thinner 409 cut faster. Buying 409 in bulk will more than make up for the occasional breakage, but wear safety glasses. In the end they worked well and the quality was good, but personally I prefer the 409.