what I don't see in your post is how the sizes act each time if you are at 1.20 and dial in .010 do you get1.270 or something different. then you dial .n .010 again do you get 1.260 if you do then don't change anything and take the final cut it should come out on size if none of the other sizes came out then start figuring out if yo are going over and compensate for the change learn your lathe sometimes they will stick and then jump. put a dial indicator on the carriage and watch it move. buy the way in the machinist world tenths is short for ten thousandths .1 tens, .01 hundredths .001 thousandths .0001 ten thousandths abbreviated tenths so we don't have to say so much each time bill