# Cut concrete with angle grinder



## Jack E (Mar 22, 2010)

I’m putting a bathroom in my basement and need to create channels in the concrete floor to tie drains in to the main stack. I’m thinking about 4’ of channel. I’ve read on this site and others that some folks use an angle grinder to cut the concrete. What would be the best approach if I went with this method? Would I make a series of cuts than whack at it with a sledge? I’d like to avoid cracking the concrete beyond the channel. Will the “masonry cutting” wheels sold at HD work? I have a hammer drill with a chisel that I could use. I’m guessing 4” floor with no rebar (hopefully.) Thanks for the help.


----------



## oh'mike (Sep 18, 2009)

I just use an electric jack hammer---I seldom cut the concrete if tile is to be set over the cut area---

A cut only need to be an inch or so deep to give you a neat edge when jack hammering.


----------



## Jack E (Mar 22, 2010)

oh'mike said:


> I just use an electric jack hammer---I seldom cut the concrete if tile is to be set over the cut area---
> 
> A cut only need to be an inch or so deep to give you a neat edge when jack hammering.


I like the idea of using the jack hammer because I imagine it would create less dust. I'm a little freaked out about the dust and how to manage it. I will be laying some type of floor on top of the concrete so it doesn't have to look pretty. Thanks


----------



## hammerlane (Oct 6, 2011)

here is a decent video:

http://www.youtube.com/watch?v=nYZpkW3vdTU


----------



## stadry (Jun 20, 2009)

here's what we do: 
1 - make 2 cuts as/where needed w/demo saw that has a wet attachment ( most rental yards' saws are so equipped ), whack the cut conc w/hammer, lift out broken pieces;
2 - make 2 1" deep cuts w/4" angle grinder & finish cutting trench w/elec hammer & point or 1" chisel bit - less dust if you hold the sucker hose from a good wet dry vac near the blade;
3 - using 4" grinder w/dust shroud attachment, do #2 & add a wet/dry vac to the shroud
4 - buy shoud from dustless technologies or joe due [ no $ interest ]

the video's funny - he doesn't know there are effective dust collecting shrouds avail to fit saws ( gear-drive ) - when i saw the direct-drive circle saw, i quit watching

concrete cutting as above isn't dust-free but its manageable


----------



## Jack E (Mar 22, 2010)

Thanks for the responses and ideas. I’m trying to figure out the best approach considering cost, dust management and labor involved. I’m on somewhat of a tight budget so I’d like to try to use the tools I have if possible. I have checked out the hood systems for the grinder, they look pretty slick but kind of expensive for a one-time use. The wet saw rental is going to be around $150.00. I haven’t checked yet but I’m thinking an electric jack hammer would be less. For those who have used an electric jack hammer for this type of project, do you think the jack hammer would create a decent channel without breaking concrete all over the place? It seems like the jack hammer would be the quickest with less dust but I have no experience to draw on. Thanks


----------



## hammerlane (Oct 6, 2011)

itsreallyconc said:


> the video's funny - he doesn't know there are effective dust collecting shrouds avail to fit saws ( gear-drive ) - when i saw the direct-drive circle saw, i quit watching


Dindnt notice that.:thumbsup::thumbsup:


----------



## stadry (Jun 20, 2009)

IF our circumstances were yours, we'd pick small bosch bulldog chipping gun & point or small chisel bit :thumbsup:


----------



## Jack E (Mar 22, 2010)

Hi all – I wanted to loop back to share how my project worked out; maybe it will help another DIYer with a similar project. 


I rented a Makita jackhammer with a point chisel and a flat chisel from HD for four hours ($50.00). I used the point chisel to outline my trench and to poke various holes inside the trench. I used the flat chisel to break-up the concrete. It took about 1.5 hours. The dust wasn’t too bad and was manageable with a shop vac. If you don’t know the direction the main stack is going underneath the concrete (I didn’t) be careful until you get enough pipe exposed to determine direction.


----------

