Fraid Miller is correct even about things he can't precisely recall. Wire size twist drills don't change size by a consistent increment but 3 to 6 thousandths" seems about average. Far cry from 5 ten/thousandths" difference bore to shaft which I assume gives a "sliding" fit. For instance in the roughly 1/8" range we're considering, a #30 twist bit is .1285" dia. A 29 is .1360" dia. or .0075" difference. Maybe I should play a machinist on TV as my idea of clearance between axles and bores is only off by 14 or 15 magnitudes! Oh well!!
jack
