cant help with that one, I did not know whit did sub 1/32 jumps all my taps and dies are in 1/32 increments from 1/16 to 1/4 then 1/16 jumps to 1"
EDIT: I could not have been more wrong, my little presto book says 1/64 increments from 1/16 to 1/4 then 1/32 to 3/8 then 1/16 jumps to 1" Wonder if anybody still sells the 64ths taps and dies, maybe watchmakers still have them?