Build up a hole in the ceiling a bit?

[specter]

I have a hole in the ceiling (gypsum) which is now covered with a junction box cover 10cm. https://www.kjell.com/se/sortiment/...ptillbehor/doslock/doslock-slat-100-mm-p37616 On the junction box cover, I have glued a smoke detector that sits well.

The problem is that the snap fastener doesn't clamp properly because the hole is a bit large.

I have tried gluing with double-sided adhesive, but it doesn't hold very well. I also tried taping around the snap fastener to cover a larger area, but that didn't work well either. What should I do?

I am now mostly considering trying to reduce the hole in the ceiling so that the snap fastener can then work. But how do I do that? If I use some filler, I assume it will come off. Is there a type of compound that can be applied which becomes really durable when it dries?

There is electricity nearby so it shouldn't be flammable either.

 

[hul]

plaster the hole again and make a new hole in the correct size

 

[Detraw]

Put up the dose lid and apply latex caulk around the edge and smooth it out, it usually helps to keep it in place. Can't swear it will hold up the smoke detector but otherwise it works just fine...

 

[specter]

Latexfog might be a sensible idea. I'm considering trying to draw a string around the entire hole to make it smaller in circumference, and then wait a day until it hardens and try to lift the whole piece.

 

[Peter2400]

I had solved it with my rechargeable glue gun
I use it for most things, always ready and hot in 10 seconds.
https://www.bygghemma.se/hus-och-by...ktyg/limpistol/limpenna-bosch-36v-li/p-314278