Oops - forgot last Wednesday's update; started setting 5 in a row. 3.75mm stones, 3.9mm centre to centre on the bearings. The stones are all in, with 4 grains apiece, and I've started cutting the surround for them; tomorrow I should finish it, raising some additional grains between the stones. The cutting's only rough at the moment, so I'll hold off on the photos at the moment.