Brass being copper and zinc, even with other alloying material, a cutter making less than 100 cuts doesn't speak well for the quality of the cutter material. It seems reasonable that there are a number of milling cutters available. Even that you might make an adapter for 1/8" or 3mm dental drills or Dremel cutters. Sized to match the guide pin would be the only real consideration, an adapter is common enough.
Just a thought, I let go of my key machine years ago, after I retired.
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Just a thought, I let go of my key machine years ago, after I retired.
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