How to use a hole saw without a center bit?

[JOB The Builder]

Installing ceiling panels in a room. Unfortunately, the electrical junction box ends up at the seam between like three panels. Such is life... :|

The thing is, the box is already in place with electricity in it, how do I saw a hole in the panels with a hole saw without being able to use the center drill bit in the hole saw? The center drill bit would ruin everything in the junction box And without the center drill bit, the hole saw tends to wobble quite a bit...

Grateful for smart tips

 

[mexitegel]

Skip the hole saw and use a knife instead.

 

[cecar33]

Is it not possible to move the cables aside and mount the magnet, and then proceed carefully, but cut the power before you saw?

 

[Helioz]

You could cut out a hole plate which you then screw to the ceiling to guide the hole saw.

 

[JOB The Builder]

Skip the hole saw and use a knife instead.

Knife?!? The board is hard enough to saw as it is with a regular handsaw Knife sounds a bit... heavy I doubt I could even make a hole in the board with a knife... But thanks for the tip!

 

[JOB The Builder]

Can't you move the cables aside and mount the magnet, then proceed carefully, but cut the power before you saw

Move the cables aside, yeah maybe that could work... But what magnet are you talking about?!? Cutting the power sounds like a brilliant idea

 

[JOB The Builder]

You could cut out a guide plate which you then screw into the ceiling to guide the hole saw.
[image]

Yes, I have used guide plates before when I installed junction boxes in the wall; the thing was that I would later be renovating the wall. This ceiling is brand new, and I'm not really keen on screwing the guide plates into it I had the same thought, I just don't know how to make it stay in place...

 

[Ludwig]

Cut the center drill bit a little and go almost all the way through with the saw part. Take the last bit with a knife if you don't dare to take a chance.

 

[VikHe]

This is how I did it when the person who installed the ceiling didn't bother to make a proper hole...

To clarify, the center drill in the picture is only there to center the block, I removed it before drilling.

 

[dsub]

Skip the center drill and hold the hole saw at an angle so that you are only drilling with a few centimeters on one edge; as you drill deeper, slowly tilt the hole saw back, and it will be perfect. Test on a scrap piece first to get the technique down.

 

[mexitegel]

Knife?!? The board is difficult enough to saw with a regular handsaw Knife sounds a bit... heavy I doubt I could even make a hole in the board with a knife... But thanks for the tip!

Haha, I can see I didn't read your post properly. I got the impression it was ceiling gypsum .
I see you've received many other good tips now

 

[Demmpa]

Push aside the cables, yeah maybe that could work... But what magnet are you talking about?!? Cutting the power sounds like a brilliant idea

Hole-in-one magnet
http://elbutik.se/product.html/magnetsok-15-dosa-hole-in-one

 

[Ludwig]

Or Biltema's variant if they still have it? Works just as well and is a bit cheaper. . And more or less identical.

 

[Larsa]

Hole plate model a little larger can be fastened with boards to the floor