Most cutters come with standard geometry, designed to cut through a single piece of steel.

They cut quickly, and produce a clean hole. The slug that’s ejected looks similar to a top hat, with a small lip on the bottom edge. But, if you’re cutting through multiple pieces of steel, standard geometry isn’t for you. You’re looking for Stack-Cut geometry.


Let’s look at the differences. Standard geometry cuts from the outside to inside. You can see how the teeth of this cutter slope inward. On stack-cut geometry, the teeth cut inside out. This produces a perfectly round cylinder without that lip.


If you used a standard cutter on multiple pieces, you’d have to stop between pieces of metal and try to fish out that slug before continuing. Or risk breaking your tool. Hougen has a complete series of both basic standard geometry bits, as well as stack-cut versions. Now you know the difference and can choose what’s right for your job.


We have a great demo of the Hougen 904 MagDrill, done by Jim Kaiser of Hougen Manufacturing. Click right there to see the drill in action. Then head over to GME supply, where we have a full selection of Mag Drills, cutters, and accessories.