A long time ago, in an issue far, far away…the May 2014 issue of KITPLANES, to be exact…The Home Shop Machinist covered the ins and outs of using the Quantum jig to DIY drill bolt heads for safety ...

See a letter "A" on your drill bit? You're holding the first and smallest size in the letter-gauge drilling system. Perhaps unsurprisingly, this standardized series runs alphabetically from A to Z. On ...