I have an 8 mm Lorch "German," pre WWII, and maybe pre WWI, with numerous accessories. The headstock pulley has a series of small holes around perimeter, that, normally, I think, are similar to ones found on American WW lathes, for engaging a spring loaded pin, to stop pulley travel along those holes. However, this lathe has no pin, no hole for pin, no nothing that I can see, for engaging those holes, so what are those holes for? They are very small pin holes.