This is the second magnetic drill I've built. In this project, I used three magnetic door lock to build electromagnet. Each magnetic door lock has a maximum pull of 180kg, giving o total of 540kg. I used a laptop power supply, I also tried to connect the magnetic door lock to a 12v 3A power supply, but on this power supply to heat up. The electromagnet is really strong, strong to drill in any position without worrying about the drill falling.
In this project i also decided to build another feed mechanism, which is much more stable and no backlash.