Cutting plaster walls, your method

[M4gery]

I have a lot of older houses in my area with plaster on wood lath. My method has always been to use a Rotozip with a tile bit to cut out holes for boxes. This is VERY dusty, having a vacuum there helps keep the dust down but some dust still escapes. The tile bit also burns the wood lath quite a bit so most times I switch to a wood bit making it a two step process.

I was thinking about trying out one of those oscillating tools like the MultiMaster/Sonicrafter/etc. However, I did a small bit of research and found no blade specifically made for plaster (or tile).

Does anyone use this type of tool for plaster and wood lath? How do you like it? What blade do you use and how many cuts do you get?

If anyone has another method for cutting plaster on lath, I am all ears.

Thanks for the input.

 

[PetrosA]

Don't laugh, but I still find scoring with a straight screwdriver, chisel or painter's tool, then removing the plaster by hand and cutting the wood with a sawzall (you have to use a very sharp blade) or jigsaw works best. I make my first cut towards the center of the bay, then cut closer to the stud which helps keep the lath from shaking plaster loose. If the lath is really loose, I hold it with channellocks or pliers but generally it's enough to press against it to hold it steady.

 

[HEYDOG]

This is not a answer to your question but may be relevant. I don't know if you are aware but the epa has a requirement that if you are removing so many square feet of wall that may have lead in it that you have a certified abatement person on the job sight. You would need to search the web to find it and see if it is applicable in your area. Mostly I think it was pre 1978 construction.

 

[480sparky]

This is not a answer to your question but may be relevant. I don't know if you are aware but the epa has a requirement that if you are removing so many square feet of wall that may have lead in it that you have a certified abatement person on the job sight. You would need to search the web to find it and see if it is applicable in your area. Mostly I think it was pre 1978 construction.

It's called the RRP (Renovation, Repair & Painting) Law.

Click here.

 

[1793]

Don't laugh, but I still find scoring with a straight screwdriver, chisel or painter's tool, then removing the plaster by hand and cutting the wood .....steady.

I do the same with one exception, I will use either a Key Hole saw or my MultiMaster to cut the lath. I cut just about all of the way through each side but leave just a bit, then I use my straight screwdriver inserted in the cut and twist, lath breaks out clean.

 

[Dennis Alwon]

Don't laugh, but I still find scoring with a straight screwdriver, chisel or painter's tool, then removing the plaster by hand and cutting the wood with a sawzall (

I do also then keyhole saw , but I wonder if a rotozip with a saw blade. Don't know if they make one for plaster but they do have carbide cutting blades that may work well.

The problem is with the metal lathe, if it has some. That becomes more difficult.

 

[LarryFine]

I was thinking about trying out one of those oscillating tools like the MultiMaster/Sonicrafter/etc. However, I did a small bit of research and found no blade specifically made for plaster (or tile).

Yes, the oscillating tool does have a blade that will cut plaster:

Then, switch to the fine-tooth wood/metal blade for either type of lath.

 

[PetrosA]

I've thought about a multimaster or knockoff, but there's no way I'm spending money on a rotozip. There's no excuse for that amount of dust or noise

The thing about a multimaster is that I'd use it so rarely it's kinda hard to justify the expense or the space in my truck for it.

 

[LarryFine]

The thing about a multimaster is that I'd use it so rarely it's kinda hard to justify the expense or the space in my truck for it.

Have a Harbor Freight near you?

 

[busman]

Jigsaw with tile cutting (abrasive blade).

Mark

 

[M4gery]

Don't laugh, but I still find scoring with a straight screwdriver, chisel or painter's tool, then removing the plaster by hand

So you basically just score the plaster and then break it out? That seems like something that I would crack the wall or loosen the lath if I tried it.

The Rotozip cuts through plaster so nicely.

 

[M4gery]

Yes, the oscillating tool does have a blade that will cut plaster:

Then, switch to the fine-tooth wood/metal blade for either type of lath.

I see. I thought that blade was only for grout, but it makes sense to use it on plaster. I was mainly looking at the edge cut blades which is why I never found a plaster blade. Thanks.

 

[PetrosA]

So you basically just score the plaster and then break it out? That seems like something that I would crack the wall or loosen the lath if I tried it.

The Rotozip cuts through plaster so nicely.

Yeah, but the clean-up is a nightmare. I can't even imagine using one in a finished house to add a switch or receptacle. You might loosen lath a little bit but it generally won't compromise the plaster. The only time it doesn't work well is if the plaster is so bad that it comes off in chunks. At that point no method is going to give you good results since the walls probably aren't going to tolerate even the smallest amount of vibration and they definitely won't hold a box well.

 

[OregonSE]

I have a lot of older houses in my area with plaster on wood lath. My method has always been to use a Rotozip with a tile bit to cut out holes for boxes. This is VERY dusty, having a vacuum there helps keep the dust down but some dust still escapes. The tile bit also burns the wood lath quite a bit so most times I switch to a wood bit making it a two step process.

I was thinking about trying out one of those oscillating tools like the MultiMaster/Sonicrafter/etc. However, I did a small bit of research and found no blade specifically made for plaster (or tile).

Does anyone use this type of tool for plaster and wood lath? How do you like it? What blade do you use and how many cuts do you get?

If anyone has another method for cutting plaster on lath, I am all ears.

Thanks for the input.

In Oregon they are cracking down on remodel work pre 1978 structures with lead paint. If they have kids and your stirring up lead dust be aware of the new laws as of april 2010.

http://www.epa.gov/lead/pubs/renovation.htm

 

[goldstar]

I use the Fein Milti-master exclusively for these cuts. If you don't want to spend the $400.00 for one of these, Dremel and Bosch make somewhat comparable machines. Don't bother with the Rockwell, it's a piece of junk.

There is a flooring company in Milwaukee (Imperial Blades) that makes specialty blades for the Multi-master units. This summer I purchased carbide tipped blades (about $14.00@) and I've cut through concrete composite siding and plaster with the same blade. I've probably made about 25 cuts thus far and the blade is still like new. I also purchased a diamond tipped blade (about $50.00) that I haven't used yet so I can't attest to it's ability. Once you cut through the plaster, change blades to a fine cut wood blade for the lath.

If you decide to purchase one of these tools check this site out and buy some of their blades. Worth every penny.

www.imperialblades.com

 

[shepelec]

I chisel out the plaster with a knife and screw driver, then use a roto zip on the lathe. That way the dust is minimal and you don't risk blasting out the plaster.

 

[Dennis Alwon]

Bosch has a cordless one that comes in a kit with an impact drill , I believe, for a few hundred. I heard it was good

 

[jerryalan]

cutting in boxes

cutting in boxes

i use a 2" hole saw and slow speed. i've had pretty good luck with Lenox.
in some parts of the country, (Detroit, Montreal), the walls seem to be made of a hardier material than others, but the 2" works best for me, very little dust and a tight fit.

 

[ptonsparky]

For low dust you cant beat scoring with a screwdriver or chisel. I have odered the sawzall blades with the diamond grit. They worked well and cut the lath cleanly. Place the box as close to stud as you can and plan your cuts as previously described.

 

[renosteinke]

I have used the Fein Multi-master, and it is the cats' meow for our work. You have superb control, can make very small adjustments to your cuts, and there is NO airborn dust.

The dust seems to be made of fairly large particles, and these either sit atop the blade, or fall straight to the floor.

I used a circular blade with a carbide grit on the edge. I expect the toothed steel blade would also work- maybe faster, at a shorter life.

The Fein I used was an early model, and did not have speed control.

One big advantage of this type of tool is that there is nothing that will snag on things in the wall, or shake the wall about. The oscillations are too fast and small for that to happen. I've had other methods do extensive damage around the opening, as the blade grabed on to something. If the plaster has a wire mesh in it, I would not even consider any tool but a multi-master for cutting into it.

As for other makes, let me summarize the comments I've heard:
1) Stick to corded tools. Even Fein is disappointed with their cordless versions. The Fein has a 12-ft. cord IIRC;
2) The Dremel version is junk- it overheats and burns out quickly;
3) The $30 Harbor Freight version is reported to work just as well as any other version;
4) Bosch is selling an adapter that will let you use anyone's baldes;
5) It seems that Fein is the only one that comes with a decent case, and an assortment of blades; and,
6) There are places that will sell the Fein for $250 - making it competitive again.

Now, as for dust pick-up .... and I'm sure you already know this, but I will feel better if I say it anyways:
1) Ordinary vacuums are instantly murdered by drywall dust. If you use a shop-vac, get a HEPA bag for it, as well as a HEPA filter. It may seem silly putting $60 worth of filters in a $30 vacuum, but trust me on this one; and,
2) The DeWalt vacuums, while not called "HEPA," are intended to be used for picking up drywall dust. Performance suffers when used with battery power, but for a single cut-in box they're a great thing to have in hand.