Tips for chasing into hard & brittle brick ?

[SimonH2]

Working in my new (to me) home, build in 1960 using hard red bricks.

To make chiselling easier, I've tried drilling lots of holes but ...

Hammer drill doesn't work very well at all - needs lots of pressure, makes slow progress, and tip gets quite hot.
Tried the SDS drill, and it broke the brick near the vertical (mostly) and horizontal mortar joints. I just hope no plaster came off in the next door neighbour's back bedroom !

Any other tips, other than patience and building up the arm muscles ?

PS - no I'm not keen on shallow boxes. All that will go in without chasing the brick is 16mm.

 

[JohnW2]

If the bricks are very hard and brittle, IMO your best bet would probably be a grinder - but it will make the mother and father of a mess - probably throughout the house!

Kind Regards, John

 

[333rocky333]

Dont do a lot of chasing, but i was once taught its better to use a small sharp chisel about 10mm wide rather , than a bigger one

 

[ekmdgrf]

Whichever way you go about it, chasing will always be a pita. You have three main options:

1) the old fashioned way, with hammer and chisel. It's really, really, really slow and really, really boring too. You can try drilling holes but you'll get bored of that even more quickly than hammering away

2) SDS drill with chisel. This is fairly quick but brutal. When it comes to the backboxes, expect to have to put filler in the hole before the backbox

3) Chase cutter. These are awesome. Basically two angle grinder discs parallel to one another. Cuts two lines down the wall, then you knock the middle bit out with a chisel with ease. Down side is that it costs around £100 and makes that mess that John was talking about. It's also not a great deal of help when it comes to backboxes. If you don't have one you can always use an angle grinder. The advantage of the chase cutter, other than doing both cuts at the same time is that it comes in a nice enclosure that you can attach a dust extractor (aka Henry) to. I'm not sure why you do that since you still get dust on every single surface in every single room in the house.

 

[bernardgreen]

When using a grinder to cut chases it helps to keep the rest of the house dust free if you fit powerful extractor fan on a sheet of plywood and fill a window opening with it.

By blowing air and dust out of the room the replacement comes into the door under doors etc and prevents dust going out to the rest of the house.

The down side is it can turn a green lawn red ( or whatever colour the wall is ) and may upset near neighbours.

 

[SimonH2]

Thanks for all the tips - looks like I've not overlooked some neat trick that would make it really easy

I remember Dad used to use a big fan when making a dust - but back then it was easy with sliding windows. When I say big fan, this was something like over 1ft in diameter and with it running it was virtually impossible to shut the room door. Now we have these modern plastic windows with the complicated hinges I can't see an easy way to fit the fan I have without marking the frame.

I've also been using a small sharp chisel. Yes it does work a lot better, then I finish off with the bolster.

On the upside, unlike the "lumpy" concrete blocks, I end up with nice flat holes - mostly because I just don't take out more brick than I need to.

Next stage means working on a single brick wall - I definitely won't be going near that with the SDS

 

[seasickstevie]

If you're doing a lot, these are a good help

http://www.sitebox.ltd.uk/clarke-ca...paidproducts&gclid=CI_a5Pj6zsECFSPItAodU3wAEA

 

[SimonH2]

Yes, looks the job.

Forgot to mention, so far it looks like chasing for conduit isn't an issue as the bonding coat is quite thick - thick enough to swallow white oval conduit or the 16mm backboxes I'm putting in for wall lights.

Thinking a bit more about the fan I've got ...
Turning things around, I might try putting it at the back to door pressurise the whole house - it'll do the same job as de-pressurising the room I'm working in. Just need to improve the guards a bit as I don't want diced cat or dog

 

[bernardgreen]

I might try putting it at the back to door pressurise the whole house - it'll do the same job as de-pressurising the room I'm working in.

That would work but you may have to seal up a few leaks around the whole house like loft hatches and fireplaces with chimneys etc etc.

 

[stillp]

Turning things around, I might try putting it at the back to door pressurise the whole house - it'll do the same job as de-pressurising the room I'm working in.

If you pressurise the room you're woking in higher than an adjacent room, you'll force the dust into that adjacent room.
Don't forget to wear adequate respiratory protection, not just a disposable cup mask from the DIY shed.

 

[ekmdgrf]

The down side is it can turn a green lawn red ( or whatever colour the wall is ) and may upset near neighbours.

Brick dust is offensive. It will clog a vacuum cleaner in a nano second. Once the dust settles, sweep up what you can and maybe even get the next lot with a damp cloth. Don't get a Dyson on it, the filter clogs almost at once and then needs washing and drying for 12 hours. Henry lasts a little longer but you can take the filter outside and shake it off.

 

[ban-all-sheds]

 

[stillp]

That looks a useful tool BAS, and though ridiculously expensive it can be hired. Still makes dust, but looks a lot less than a grinder.

 

[ban-all-sheds]

Still expensive, but not as ridiculous, in its native land.

http://audel.com.au/arbortech-as170-brick-mortar-saw/



It looks like a lot less dust.

 

[stillp]

I wonder how much chasing could be done with one of those vibrating multi-tools?
I had to cut some panelling with one of those, and found I'd cut a very neat kerf into the bricks underneath, without even noticing! Admittedly they were soft bricks, but then again the multi-tool was a cheapo from Aldi.