# Modifying old plaster and metal mesh walls



## Guap0_ (Dec 2, 2017)

The gang boxes should be screwed or nailed to the studs not set in the plaster. While you may have to chip away a little of it, you don't have to do any major surgery.


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## joecaption (Nov 30, 2011)

I'm confused, why do the boxes need to be replaced?
Do you own this house?
We have no location, no idea how old this house is.
Not even sure from your post what it is your trying to do.
Trying to upgrade the wiring so it has a ground?


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## Ryanack (Mar 15, 2018)

Im trying to find the right tools to cut into these walls without destroying too much, is the main problem.
I think it's too hard/thick to cut with any sort of utility knife, I've heard something like an angle grinder might work, but I didn't know if anyone had better/easier ideas.
Basically the electric box isn't the only thing I want to know this for. I want some help knowing how I can cleanly get into the walls where I need to.


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## Nealtw (Jun 22, 2017)

This will get you thru the concrete 




 
A jig saw with a metal blade will get you thru the metal lath.


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## Gregsoldtruck79 (Dec 21, 2017)

The links are what I bought to cut my homes 1959 model "button hole " plaster, but it has no wire mesh. (except in the corners) I cut the box opening with the grout removal blade. The wire mesh could then be cut with the wood/metal combo blade if, the grout blade does not. 

Cut all the openings first with the grout blade, change blades, then go back and cut the metal. But FIRST find your studs by using a sacrificial 1/16" drill bit. Plaster eats any blades/drills/hole saws up fast that are not diamond embedded. All JMO


https://www.homedepot.com/p/Dremel-Multi-Max-3-3-Amp-Variable-Speed-Corded-Oscillating-Tool-Kit-with-10-Accessories-and-Carrying-Bag-MM30-04/206360248



https://www.homedepot.com/p/Dremel-Multi-Max-1-1-4-in-Oscillating-Tool-Flush-Cut-Blade-for-Wood-and-Metal-MM482/202895808




https://www.homedepot.com/p/Dremel-Multi-Max-1-16-in-Grout-Removal-Oscillating-Tool-Blade-MM501/100659461


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## ClarenceBauer (Mar 4, 2005)

Gregsoldtruck79 said:


> The links are what I bought to cut my homes 1959 model "button hole " plaster, but it has no wire mesh. (except in the corners) I cut the box opening with the grout removal blade. The wire mesh could then be cut with the wood/metal combo blade if, the grout blade does not.
> 
> Cut all the openings first with the grout blade, change blades, then go back and cut the metal. But FIRST find your studs by using a sacrificial 1/16" drill bit. Plaster eats any blades/drills/hole saws up fast that are not diamond embedded. All JMO
> 
> ...


 The above advice is very good. Some other things you should do if you want a work hole in the plaster and say it is 4 inches sq. than cut the plaster back 6 inches DO NOT cut the lath at this point.
Remove the plaster from the metal lath than cut the 4 inch opening in the lath this leaves 2 inches of lath exposed to attach the repair lath to. Push the exposed lath inward as this material WILL CUT your hands.
Yes a side grinder may be used if used you will need an foot attachment to gage the depth. Other tools that may be used Die hand grinder with a cylindrical shaped carbide bit use the flat end bit so as not to cut into the lath. I don't think you will find any but to be sure to check for Asbestos & lead paint.


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