I am a bottom feeder, don't like to spend money on store bought stuff and often can't even get to the power tools and drill presses. I have an aluminum bar that fits snuggly into the shell. I mount a sharp kitchen knife (well, actually my asparagus cutting knife) in a wide jaw vise with the blade barely protruding for several inches. I "roll" the shell over the protruding blade like a rolling pin, cutting the unwanted crimp area from the shell. No fuss, no muss, no cutting on a spiral. Just remove the shell and when mounting the next shell, the cut off section of the previous shell slides up the aluminum bar. The cut is very neat, no power tools involved and no replacing of fragile razor blades. However, John E's method looks fast and easy as long as the correct blade is used on the saw.
