Pipe outlet with cable in ceiling - how to drill a 50 mm hole around the pipe?

[Lund]

I have a rather trivial yet tricky problem. A pipe with a network cable comes down from the ceiling, and a 50 mm hole needs to be drilled so a camera can be pushed up into the hole.

But how should I drill without damaging the pipe and cable?

 

[David-O]

Is it possible to pull the cable into the pipe?
If so, use a hole saw and drill a hole in a board/plank.
Place it over the hose, remove the center drill in the hole saw, and use the hole in the board as a guide.

 

[Lund]

Can you pull the cable into the pipe?
If so, take a hole saw and drill a hole in a board/plank.
Place it over the hose, remove the center drill in the hole saw and use the hole in the board as a guide.

Well, I can get the pipe in a bit, but the cable feels stiff, so it doesn't go all the way into the pipe/hole unfortunately.

 

[lordi]

Is it plaster? Draw a circle and drill a bunch of holes with a smaller drill along the marking. Then you can cleanly cut it with a sharp knife.

 

[David-O]

Then I would probably take a small drill and drill many holes inside the edge of a 50mm diameter circle and then chisel/cut/saw + file if it needs to be evened out.
(2a on that )

 

[Lund]

Is it plaster? Draw a circle and drill a lot of holes with a smaller drill along the marking. Then you can cut it clean with a sharp knife.

Then I would drill many holes inside the edge of a 50mm diameter circle with a small drill and then chisel/cut/saw + file if it needs to be smoothed out.
(2nd on that )

Thanks for your input, I'll try something like that and see if I can succeed.