We aren’t sure that [John Heisz’s] build is really what we think of as a drill press, but it is a very portable way to convert a regular drill into something like a drill press. Your drill will probably be different, but you can follow along with his build in the video below.
On the face of it, it doesn’t seem like this would be very hard, but there are a few tricks. Finding the exact center of the drill axis on the back of the drill takes a bit of effort.
[John] has a well-equipped woodshop, so he fashioned everything out of wood. We couldn’t help but think that a laser cutter or 3D printer might have made easy work out of some of the pieces, even if you might have had to laminate thinner plywood together for thickness with the laser cutter.
The wood slides seem to work well, but we thought it might be useful to use rails like some 3D printers use or even cabinet slides. The basic idea is so simple that you should be able to modify it and extend it with your own ideas.