Historical
ISO 3438:2003
Subland twist drills with Morse taper shanks for holes prior to tapping screw threads
ISO 3438:2003 lays down the dimensions of subland twist drills with Morse taper shanks for holes prior to tapping screw threads. The drills have been designed to produce holes prior to tapping metric threads (coarse pitch series) over a selected range of M8 to M30. ISO 3438:2003 complements ISO 2306.
International Organization for Standardization [iso]