[konjin]

>If you are a software guy, drilling a 12mm horizontal hole 30mm deep into the edge of a 20mm x 400mm plate is surprisingly difficult.

Punch to center the first hole, then a center drill to start, then pilot holes at 3mm, 6mm and 12mm, use duck tape on the drill bit to keep the depth right.

If you really need the holes to be dead straight use a handheld router those are a great thing to have anyway and pretty much all of them have 100mm of or so of travel.

If you're drilling into something very hard skip the 3mm.

A good video on how to tap so you break fewer of them: https://www.youtube.com/watch?v=33wfSMsUbuc

[dekhn]

this is one of the main reasons I bought a CNC- to automate work that I can do precisely, but am too lazy to complete.