I did this before too using Dremel cutting (flat) wheel using super low speed (to avoid heat) at 1000-2000 RPM. BTW get glass of water with ice to cool down blade. It does take some time but blade was pretty cool during cutting. Also remember face blade away from you and don`t forget about your personal safety. My end up with round point which "virtually" extending blade. Really take your time and I manage cut blade without any problem. Now one thing... polish end of blades (after cut) on the sandpaper, rounded (if you choose round point) as well piece of paper. Do not use Dremel or other tools. Why... as I think after cutting you already stress blade to level when it can chip... again.