I wanted to install a new bottom bracket on my messenger bike project, but it needed a special wrench. Rather than spend more on the wrench, than the rest of the bike, I made my own.This was machined on a home built router out of 1/2 thick HDPE (cutting board). The part is drawn for use with a 1/16 diameter mill. I did a first pass with a 1/8 end mill and planned to do a final profile with the 1/16th, but the part fit fine as is.The step height is 1/8"