Cutting drywall with rotozip type tool - how is the drywall held?

[Stephen Tashiro]

There are many videos on the web showing how to cut holes in drywall for electrical boxes by using a rotozip type tool. However, they don't make it clear how the sheet of drywall is being held in place during the cutting. Is the drywall just propped against the wall? Is it held in place by a few screws at the top?

[Doug Dawson]

There are many videos on the web showing how to cut holes in drywall for electrical boxes by using a rotozip type tool. However, they don't make it clear how the sheet of drywall is being held in place during the cutting. Is the drywall just propped against the wall? Is it held in place by a few screws at the top?

A few screws at the top, not drilled in all the way (gives it some play,) so the sheet is leaning against the box.

[Flamone LaChaud]

Our contractors for the drywall on the ceiling ringed the very edge of the cam light housing with a bit of white paint, then pressed the drywall in place so that there would be a mark on the back where the hole needed to be cut. Pulled the drywall down, zipped out the hole, then installed it properly. When I had to go back and make another hole once the drywall was in place - that dust made by cutting just clogged my Dremel to the point where even after disassembling it and cleaning it . . . it's just not worked right since. So whereas it works awesomely making holes in walls - it's not good for making holes in ceilings.

[Steve Rozmiarek]

Our contractors for the drywall on the ceiling ringed the very edge of the cam light housing with a bit of white paint, then pressed the drywall in place so that there would be a mark on the back where the hole needed to be cut. Pulled the drywall down, zipped out the hole, then installed it properly. When I had to go back and make another hole once the drywall was in place - that dust made by cutting just clogged my Dremel to the point where even after disassembling it and cleaning it . . . it's just not worked right since. So whereas it works awesomely making holes in walls - it's not good for making holes in ceilings.

The rotozip tool has dust protection built into it and while it's still a filthy mess to use, the tool doesn't care. They make a model with some dust collection built in, I've not tried it though.

[Steve Rozmiarek]

A few screws at the top, not drilled in all the way (gives it some play,) so the sheet is leaning against the box.


Exactly, just don't put screws too close to the box and flex the drywall away from it. The bit will jump off the box the instant it loses contact if a gap between the drywall and box allows. Leaves a funny shaped cutout that everyone will see and give you grief for until mud goes on.

[Doug Dawson]

The rotozip tool has dust protection built into it and while it's still a filthy mess to use, the tool doesn't care. They make a model with some dust collection built in, I've not tried it though.

I'm using the Makita version of it, they call it a "spiral saw", it's a bit more expensive than the RotoZip but it comes with dust collection (and a hard case, if you're into that sort of thing.) Very convenient, especially for ceilings.

[Doug Dawson]

Exactly, just don't put screws too close to the box and flex the drywall away from it. The bit will jump off the box the instant it loses contact if a gap between the drywall and box allows. Leaves a funny shaped cutout that everyone will see and give you grief for until mud goes on.

You could mitigate this by pulling the drywall out towards the screw heads (drilling the screws all the way in and then backing them out would assist., with a hook pulling the sheet from the top back; it also helps to be using longer screws here.)

[lowell holmes]

I make drywall cut outs with one of these.

https://www.lowes.com/pd/Kobalt-12-in-Coarse-Cut-Keyhole-Saw/1053303?cm_mmc=src-_-c-_-prd-_-tol-_-bing-_-tools-_-DSA_TOL_129_Power%20Tools-_-kobalt-_-0-_-0&msclkid=7dd63828b8341b14e53765652deaf645&gclid=CK3u1-OR9uMCFR-OxQIdZ1UO0g&gclsrc=ds

[Doug Dawson]

I make drywall cut outs with one of these.

https://www.lowes.com/pd/Kobalt-12-in-Coarse-Cut-Keyhole-Saw/1053303?cm_mmc=src-_-c-_-prd-_-tol-_-bing-_-tools-_-DSA_TOL_129_Power%20Tools-_-kobalt-_-0-_-0&msclkid=7dd63828b8341b14e53765652deaf645&gclid=CK3u1-OR9uMCFR-OxQIdZ1UO0g&gclsrc=ds

If the fixture is already wired up (as they usually are,) using a keyhole saw can be "tricky". I prefer not to be so nervous. :^) (Otherwise you'd have to measure out the locations on the sheet precisely while off the wall, which is a PITA.)

In general, a sheet of drywall can be like a box of chocolates, you never know what you're going to find inside, especially with renovations etc. That makes rotozip-like tools totally invaluable.

[Rich Engelhardt]

Do you already have a Roto-Zip?
If not, then very carefully review your supposed needs for one.

I found taking a used recipricating saw coarse blade, with a duct tape "handle" to be the most convienient way to make cut outs - for everything except overhead can lights.
Cost me all of the price of about three feet of duct tape.

Having said that - as others have mentioned, a Roto-Zip can be invaluable if the situation calls for it. If not, then it's just a dust catcher.

[Jerome Stanek]

This is the saw that I have used for over 40 years

https://www.homedepot.com/p/Wal-Board-Tools-1-25-in-Drywall-Saw-with-Wood-Handle-and-Steel-Blade-04-002/202954537

[Doug Dawson]

Do you already have a Roto-Zip?
If not, then very carefully review your supposed needs for one.

I found taking a used recipricating saw coarse blade, with a duct tape "handle" to be the most convienient way to make cut outs - for everything except overhead can lights.
Cost me all of the price of about three feet of duct tape.

Having said that - as others have mentioned, a Roto-Zip can be invaluable if the situation calls for it. If not, then it's just a dust catcher.

The first time you nick a wire in a wall, you will carefully review that a Roto-Zip would have paid for itself. :^) My last home theater install saw that the pre-existing house wiring had been designed and installed by Mr. Willy Nilly himself. There's just no predicting in that case, you never know for sure. There do exist tools for detecting in-wall wiring. They either don't work reliably, or else they are prohibitively expensive, or both. Why take chances.

[Rich Engelhardt]

Yep Doug - as I said, if the situation calls for it - the Roto-Zip can be invaluable.
We just finished a rehab on a rental with some (not a bunch) of drywall & non overhead - I dragged the Roto-Zip to the site & it sat there for 7 months. The sawzall balade got a workout though.

[Ronald Blue]

Watch a drywall crew. Once you see the rotozip or something comparable in use you wouldn't use anything else. The speed and ease of the cuts is far faster and neater then anything else. It might not work in every instance but there are few that it won't. Just the thought of handling a small compact rotozip versus a much heavier sawzall all day would be reason enough to have one for me. The nice thing about it is we are all free to use the method of our choice. Carry on.