Conduit pipe is generally either galvanized steel, black-coated steel or made from plastic, and is used to house electrical cables. If a hole needs to be drilled through the walls of the conduit, the circular outer wall of the conduit makes it harder to keep the tip of the drill bit in place. To remedy this situation, the use of a center punch creates a slight indentation on the pipe surface to help guide the drill bit's tip.
Place a rag on both sides of the conduit section (if not already installed) and secure it horizontally in a vise.
Mark the side of the conduit where the hole needs to be drilled using a fine-point marker. Position the tip of a center punch on the mark, ensuring that the shank of the punch is perpendicular to the conduit. Lightly tap the end of the center punch with a hammer several times until the punch's tip creates an indentation on the conduit's surface.
Place the correct size metal drill bit into an electric drill and tighten the drill's chuck with a chuck key. Rest the tip of the drill bit in the indentation on the conduit pipe with the bit and drill perpendicular to the pipe. Squeeze the drill's trigger lightly so that the drill bit moves slowly in the indentation and cuts into the side of the conduit. Push lightly on the drill while squeezing the trigger.
Increase the speed of the drill slightly when the bit cuts into the conduit. Continue until the hole is completed in the side of the conduit.