What does the letter f on a drill bit indicate?

Answer 1

Drill bits not only come in fractional number sizes they also come in letter sizes. The F size drill bit is .257 thousandths of an inch in diameter. A 1/4 inch drill bit is .250 thousandths of an inch in diameter, so size F is .007 thousandths of an inch bigger than a 1/4 inch drill bit.

Answer 2

The letter "F" on a drill bit typically indicates the size of the bit, with F being equal to 0.257 inches or around 6.53mm in diameter. This sizing system helps users choose the right drill bit for specific tasks or materials.