What is it you think you might be drilling that would require a bit that
big? The standard 1/16" to 32/64" drill sets almost always have a maximum
shaft diameter of 3/8" and it's not too often that the home woodworker is
going to use anything bigger than that. I'd say you'll be fine with what
you've got. Unless you're planning on drilling something pretty esoteric, I
wouldn't worry about anything bigger until you need it.


I have forsner bits with a larger then 1/2" shaft. but for the most part I never
use over a 1/2" shaft.

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