Perpendicular drilling guide for 11mm to 16mm metric holes

I needed to drill perpendicular 12mm and 14mm holes but could not get my hands on a drill-press with sufficient capacity (my object was taller than the usual spindle stroke and those large bits tend to be long so it all adds up)

I found strieg's design here but was not fond of the threaded bushings part and it did not cover the sizes I was after, so I quickly designed this remix using simpler bushings that you just insert in the main body/holder part.

For extra stability you can stack two same-size bushings on top of each others, but then evidently you need to print twice as many! The bushings themselves are shorter than the holder, in order to reduce printing time when you replace them (as they will undoubtedly wear out over time)

I used some high toughness UV resin. The parts already have some built in tolerance but I still needed to wet-sand the inner hole of the main part to make the insertion silky smooth. I don't do FDM printing but I'm aware those tend to not sand as well (or at all) so I'm providing two extra versions with even more tolerance (0.1mm and 0.2mm respectively)

Also provided are bushings from 11mm to 15mm in 0.5mm increments to match standard metric drill bits. They are numbered with text engraving directly on them. If you need to drill 16mm just don't use any bushing.

If ever there is interest, I can easily output other sizes like imperial or custom ones, just leave a message if you need those.