HI Guys
Seeing Moderators photo reminded me . If you want to divide 3 or six in a 3 jaw chuck . Put a spirit level on jaw 1 level it mark line on job a machine flat same on No. 2 jaw etc if you want 6 on the same setting do the same from the back . I suppose you can do the same on a 4 jaw chuck . Also i have a round plastic protractor I fit running true on a stub on the back of my lathe with a fixed pointer . Ok
for home workshop projects but not toolroom or machine shop use I may add
Regards Nobby