By all means if you have a Mizzy wheel, you're home free...I just gently hold a hump back flint in the jaws of a vise (visegrips would alsowork, laying on a bench) and using the mizzy wheel, Igrind the top of the hump's peak down enough so it becomes flat for a good grip...Idon'tgrind the whole hump OFF...not necessary...I just grind downabout 1/4"until Igetabouta 1/4" wide flat streak where the sharp ridgewas, and that does it...takes 1-2 minutes per flint...I set up a fan to blow the flint dust away from mesoI don't inhale it.