Because the thread produced by a cold forming tap is stronger than a conventional thread in most materials, it is highly recommended that 65% be taken as the proper percentage in using this tool. Much greater tool life and efficiency may be expected when tapping 65% of thread or less.

Note: It is important that tap drill charts for conventional taps should not be used for cold forming taps.

Drill Size Calculation Example:

Reference Charts:

- Drill Selection for forming taps and Decimal Equivalents

- Metric Roll Forms