Doors and Windows - Best way to bore hole in hollow door?

First time posting something here. Great forum.
I just bought 2 interior hollow doors. Stupidly I didn't check that the holes and latch plate for the door knobs were already pre-drilled.
What's the best method for drilling/boring this? The doors are just for the bathroom and bedroom so I don't need any serious deadbolt.

Thanks for any tips.

Hey Breakfield and Welcome

Go back down to the home center or hardware store, and get a lock install kit. I'd spend the extra $7-8 dollars and get the bi-metal kit, it will last much longer, esp if you ever need to do a steel door. SHould be less than $20 for the better kit. They include a little jig that you attach to the door at the correct spot, and makes it simple to do. You'll also need a chisel to do the mortice on the door edge for the latch plate. It comes with instructions...... and remember, measure 3 times, drill once.

Much appreciated. Will head back there today:)

If for some reason you can't get the jig - every lockset [door knob kit] comes with a paper template, just transfer the marks in the correct place and use your drill with a hole saw ,use a spade bit and chisel for the latch.

When the pilot bit comes thru the other side you want to quit cutting on that side of the door and finish with the hole saw on the other side.

...When the pilot bit comes thru the other side you want to quit cutting on that side of the door and finish with the hole saw on the other side.


Or you can clamp sacrificial wood to each side of the door.