Hardware and Tools - Printing in Plastic: Build Your Own 3D Printer - page 17

Figure 2-10. Using an electric or battery powered drill is possible but not recommended.
Yes, you can drill the holes, but we don't recommend it. The holes you will drill need to be
perpendicular to the surface of the parts. Using a hand drill can be tricky when it comes to making
certain the holes are drilled straight down into the plywood material.
If your only option is a hand drill, you might consider purchasing (or renting, if you can find one) a
portable drill press like the one in Figure 2-11.