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Making 30mm hole in wall

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Invisible Man

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Jan 10, 2010, 9:25:54 AM1/10/10
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Pretty basic question.

I need to make 2 holes each about 30mm diameter in a cavity wall. Usual
brick external and block internal with blown fibre insulation.

What is the best way to go about this?

This is a one off that I don't expect to do regularly so I don't want to
spend a fortune.

I have a Makita drill with a 13mm chuck rated to 20mm of concrete.
Bricks are red 1960s and not overly hard.

Thanks for any advice.

(This is one thing I can't see a way to do with my angle grinder unless
I want to do a great deal of filling)

Phil L

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Jan 10, 2010, 9:35:16 AM1/10/10
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I assume they are for pipes or cables?
Considering you are removing 60mm of brick, it would probably be best to
remove half a brick, put in your pipes and then point around with mortar.

--
Phil L
RSRL Tipster Of The Year 2008


Invisible Man

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Jan 10, 2010, 9:55:00 AM1/10/10
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A load of cables. Holes will be about 6m apart. No other practical way
to run them.

Tim W

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Jan 10, 2010, 9:58:37 AM1/10/10
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Invisible Man <invi...@invalid.invalid>
wibbled on Sunday 10 January 2010 14:25

Can you borrow an SDS Plus - loads of TCT core drills and 30mm is easy
The best way is to put a 12" pilot drill right though the wall to act as the
guide, then approach from both sides with the TCT dill (its pilot will
follow your pilot hole well enough), first on no hammer to give a clean
entry past the plaster or render or brick face. Then switch to hammer and it
will take a few minutes per leaf tops.

If you are limited to a normal drill, I think I would stitch drill it with
an 8mm bit and then work it out with a hammer and chisel.

--
Tim Watts

You know you need more insulation when the snow blanket on the roof makes
the house 3 degrees warmer...

Michael Chare

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Jan 10, 2010, 10:20:14 AM1/10/10
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"Invisible Man" <invi...@invalid.invalid> wrote in message
news:hico1j$v16$1...@news.eternal-september.org...

You can buy masonary drills that are larger than 13mm that have a reduced
end that fits in a 13mm chuck.
Just take care that the drill does not slow down to much when going through
the brick.

--
Michael Chare

js.b1

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Jan 10, 2010, 10:23:46 AM1/10/10
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www.amazon.co.uk
Blue Spot 38mm x 150mm diamond core bit - £13.17 with free delivery
a Blue Spot Arbor for your drill (hex re 13mm chuck, SDS for SDS
obviously).

Make sure you use the pilot drill and ideally drill from outside
(because it makes a talc-like dust).
Do not use hammer action, just plain non-hammer drill and it will go
through in a few minutes.
Done. Sell it on Ebay for £5-8.

Using 38mm allows you to line the hole with 1-1/2" plastic pipe to
protect cables & CWI. If you have loose polybead this bit gets fun...
you think the snow is all over... it is now :-)

The Medway Handyman

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Jan 10, 2010, 1:48:05 PM1/10/10
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You might find it easier to nip around to your local hire shop & rent a
diamond core drill bit & a drill to run it. Not that expensive for a short
hire.


--
Dave - The Medway Handyman
www.medwayhandyman.co.uk


The Natural Philosopher

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Jan 10, 2010, 5:22:48 PM1/10/10
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HIRE a core drill.

m1ss_wh1te

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Jan 11, 2010, 3:59:44 AM1/11/10
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On 10 Jan, 15:23, "js.b1" <js...@ntlworld.com> wrote:
> If you have loose polybead this bit gets fun...
> you think the snow is all over... it is now :-)

If you have loose beads inject some PU fill-foam to lock it all
together through a smaller pilot hole. Leave to cure before you drill
30mm.

Adrian C

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Jan 11, 2010, 6:56:46 AM1/11/10
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On 10/01/2010 14:25, Invisible Man wrote:
> Pretty basic question.
>
> I need to make 2 holes each about 30mm diameter in a cavity wall. Usual
> brick external and block internal with blown fibre insulation.

Shotgun.

--
Adrian C

Invisible Man

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Jan 11, 2010, 8:18:01 AM1/11/10
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A Scottish son in law has got a couple of guns. Snag would be that the
ducks on the village pond and the deer in the area might suddenly disappear!

Invisible Man

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Jan 12, 2010, 6:33:19 PM1/12/10
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On 10/01/2010 15:23, js.b1 wrote:
> www.amazon.co.uk
> Blue Spot 38mm x 150mm diamond core bit - �13.17 with free delivery
> a Blue Spot Arbor for your drill (hex re 13mm chuck, SDS for SDS
> obviously).
>
> Make sure you use the pilot drill and ideally drill from outside
> (because it makes a talc-like dust).
> Do not use hammer action, just plain non-hammer drill and it will go
> through in a few minutes.
> Done. Sell it on Ebay for �5-8.
>
> Using 38mm allows you to line the hole with 1-1/2" plastic pipe to
> protect cables& CWI. If you have loose polybead this bit gets fun...

> you think the snow is all over... it is now :-)

Many thanks for this. Ordered both from Amazon. Core drill is on its way
but they cancelled the arbor cos they hadnt got one in stock after all.
Have now sourced one elsewhere I hope pending delivery.

Invisible Man

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Jan 29, 2010, 5:01:28 AM1/29/10
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Thanks again. Drilled one hole out today - no problems.

Rick Hughes

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Feb 7, 2010, 8:23:48 AM2/7/10
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"Phil L" <neverc...@hotmail.co.uk> wrote in message
news:EAl2n.24371$Ym4....@text.news.virginmedia.com...

> Invisible Man wrote:
>> Pretty basic question.
>>
>> I need to make 2 holes each about 30mm diameter in a cavity wall.
>> Usual brick external and block internal with blown fibre insulation.

> --

> Phil L
> RSRL Tipster Of The Year 2008

Drill one hole right trough .. to get the centre line.
Draw a circle the size of the hole you want .. and drill a series of hole
around the circumference ... a 8mm or so bit, then do same other side , and
simply use a chisel to join up the holes - easy cheap, nothing to buy.

Dave Plowman (News)

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Feb 7, 2010, 8:58:06 AM2/7/10
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In article <nMGdnSxa7fF8I_PW...@bt.com>,
Rick Hughes <rick_hughes@remove_me.btconnect.com> wrote:

> "Phil L" <neverc...@hotmail.co.uk> wrote in message
> news:EAl2n.24371$Ym4....@text.news.virginmedia.com...
> > Invisible Man wrote:
> >> Pretty basic question.
> >>
> >> I need to make 2 holes each about 30mm diameter in a cavity wall.
> >> Usual brick external and block internal with blown fibre insulation.

> Drill one hole right trough .. to get the centre line. Draw a circle


> the size of the hole you want .. and drill a series of hole around the
> circumference ... a 8mm or so bit, then do same other side , and
> simply use a chisel to join up the holes - easy cheap, nothing to buy.

Takes a lot longer, needs more skill, and doesn't give as neat a job. None
of which may matter, of course.

--
*Work is for people who don't know how to fish.

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

Rick Hughes

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Feb 7, 2010, 1:12:48 PM2/7/10
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"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:50e5df1...@davenoise.co.uk...

>> Drill one hole right trough .. to get the centre line. Draw a circle
>> the size of the hole you want .. and drill a series of hole around the
>> circumference ... a 8mm or so bit, then do same other side , and
>> simply use a chisel to join up the holes - easy cheap, nothing to buy.
>
> Takes a lot longer, needs more skill, and doesn't give as neat a job. None
> of which may matter, of course.
>


OK .. hire an SDS drill 110V transformer & core drill .... neat hole quick
.... but costs a sh** load more

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