Match Drilling and Tapping Holes

[Saltfever]

** This is offered for Philip.
The imperial system "generally" uses 3 basic sizes. On this chart you will notice fractional, number, and letter sizes. Number drills range in size from .0135" to .228". In addition note the letter drill "E" is also the same size as the fraction drill 1/4". I grew up with the system so it's no big deal and as a machinist I'm bilingual in both metric and imperial.

** Everyone else: Please no "system" bashing or politics. Yes, it's easy to divide by 10 but as a machinist I have never had a perfect integer dimension in either system! When a dimension is toleranced, its either 2, 3, or 4 decimal places regardless of measurement system. I don't care if its u or ".

Edit: . . . substituted letter drills, not fractional.