Pick the Right Bit Fast

Family Handyman

No More Guesswork

Having trouble selecting the perfect-size drill bit for a particular bolt shaft? Here’s a way to drill bolt holes just the right size every time. Gently tighten the bolt in a vise. Slide a drill bit between the vise jaws, and use the gap as a gauge to find a drill bit that’s slightly larger than the bolt. — William A. Goldbach

How to choose twist drill bits.