Step 1: Materials
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Leatherman Micra - ( I used a cheapo Husky clone that I got at home depot for $2)
Keys - (be sure to make copies of them first)
Something to cut the keys with - (I used a Dremel with a cutoff wheel.
Step 2: Disassemble the Multi Tool
Step 3: Select a Matchup Piece
Step 4: Cut Your Keys
Step 5: Mark and Drill the Holes
Once you have marked all keys, mark your starting points with a punch or nail and drill your holes. The size of the hole may vary depending on what kind of multi tool you choose. Start small as you can always bore it out more if necessary.
Step 6: Put it Back Together
One little tip: If there is a skinny leather punch or mini screw driver piece, you can stick this through the hole when re-assembling the tool to help keep the washers and the pin in place. This also worked well to wiggle around to get everyting to fit together properly.
I was thinking for my next attempt to use a slightly wider, folding style alan wrench set and try to get a bunch on each side.