As I was installing a Stages crank arm on my Shimano 105 crankset I realized too late that I was missing the tool to remove and adjust the crank cap. I MacGyver'd my way through it but decided to make a tool should I ever need to adjust or re-do the work.

This part prints very quickly and certainly gets the job done as a hand tool. My cap was not that tight, but if yours is hard to remove then you may need to buy a metal tool or apply a big pair of pliers to get it off.

The part shown was printed with BambuLab PLA-CF and worked just fine. If you plan to use this a lot or decide you want more strength, go with PETG or something a bit more robust.

Also, I've included two parts - one with a very grippy perimeter and one that's toned down a bit.

Hope it helps somone in the same bind I was in! Feel free to request any modifications and I'll do my best to accomodate.