Thanks Brian for the drawing. I will set about making an Aluminum gear set. The OD of each gear is calculated as follows 31 teeth plus2 by the module 1.5 give OD for the smaller gear 49.5mm and the larger gear 87mm. I will make smaller gear with the hub spigoted into the larger gear and locktited then 3 dowels at the joint of the gear and spigot Cheers John