When I removed the fork from my Marin Four Corners 2018 I discovered the headset is not as specified. Among other problem, the crown race is some noname piece not fitting any bearing (not the one which was installed, and not the one which should be installed). The only thing it fits is a fork.
And here lies the problem, the crown race seat (on fork) has diameter 30.2mm instead of 30.1mm. The installed crown race has internal diameter 30.0 mm. Those dimensions are non-standard and so when I install the new crown race (the one it should be installed according to spec) I cannot do this because its ID is 29.9mm -- the difference is too big.
So how to adjust one to the other? One approach would be to buy a tool like Park Tool CRC-1 and strip crown race seat, but for home usage it means one time job so it is rather expensive way. The other would be to strip crown race (no perfect, because I would be altering the well made piece) but how to do it in reliable way? I.e. I don't want to scrap metal in one place, but do it evenly.
I prefer to do it myself, but I know the popular answers for bike problems is "take it to your LBS". Out of curiosity and because of tool prices I checked this option, and my LBS does not have such tools as well. They strip from crown race.