cutting opening in block wall
 

hello, I am planning to cut a larger opening in an outside wall made of blocks. There is a large window at the moment and I want to install a double french window.
I have permission from the building controls. I would like to know what tools to use and how to proceed appart from supporting the load bearing wall, which I know how to do. thank you.

On Mon, 28 Feb 2005 16:48:11 +0000, macon
wrote:


hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.

You need a long drill, to drill through in each corner of the opeing,
then a pencil and straight edge to join the dots, then an angle
grinder to make the cut. then a hammer and chizel to take out the
blocks, and a wheelbarrow to shift them away ...

Rick

Rick wrote:
On Mon, 28 Feb 2005 16:48:11 +0000, macon
wrote:


hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.


You need a long drill, to drill through in each corner of the opeing,
then a pencil and straight edge to join the dots, then an angle
grinder to make the cut. then a hammer and chizel to take out the
blocks, and a wheelbarrow to shift them away ...

Rick


I would *not* reccomend an angle grinder for this application as they
are usually direct drive electric powered, which means if they catch
whilst cutting they don't slip or stall, but propel the tool away from
the work piece. The larger ones can be a beast just to handle due to the
gyroscopic effect. Dust will be a problem too and you can't wet things
much as its electric!

I would use a stone cutter ("Stihl-saw"), which are usually petrol
powered belt driven and are a lot safer to use. You can usually wet cut
by attaching a hose pipe to these and adjust them to trickle water on to
the blade, which reduces the dust a lot.

Stone cutters can be hired from HSS/Hewden etc.

I once trimmed door aperture with a 9" grinder and would *never* do it
again like that as I value my fingers toes and especially face! I have
used Stihlsaw's too and found them to be a much better option for this
sort of work.

Alex.

"Rick" wrote in message
...
On Mon, 28 Feb 2005 16:48:11 +0000, macon
wrote:


hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.

You need a long drill, to drill through in each corner of the opeing,
then a pencil and straight edge to join the dots, then an angle
grinder to make the cut. then a hammer and chizel to take out the
blocks, and a wheelbarrow to shift them away ...

Rick


You'll know for sure when you hit a wall tie with a grinder

In article ,
macon writes:

hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.

If these are thermal blocks, a masonary hand saw goes through
them like a hot knife through butter, even if plastered (looks
like a regular timber saw, but with about 4 teeth/inch).
Actually, even a timber saw will work, but it will be wrecked
in the process and might not last for all your cuts.

--
Andrew Gabriel

Andrew Gabriel wrote:
In article ,
macon writes:

hello, I am planning to cut a larger opening in an outside wall made of
blocks. There is a large window at the moment and I want to install a
double french window.
I have permission from the building controls. I would like to know what
tools to use and how to proceed appart from supporting the load bearing
wall, which I know how to do. thank you.


If these are thermal blocks, a masonary hand saw goes through
them like a hot knife through butter, even if plastered (looks
like a regular timber saw, but with about 4 teeth/inch).
Actually, even a timber saw will work, but it will be wrecked
in the process and might not last for all your cuts.


Yeah second that.

Also, my builder mate claims to have cut the light thermalite type ones
with a handheld jigsaw as well ... but be prepared to buy a new blade!

However if its the external skin you are cutting then they are probably
medium density.

Almost backtracking a little ... I cut some medium density ones last
summer by scoring the surface with a small 4" grinder and then using a
bolster and club hammer to split them ... the difference was that I only
cut to a depth of less 1cm with the (small and easy to handle) grinder
and was I able to score all *around* the block for a clean break.

You might be able to get away with a scoring the blocks carefully in
situ, then drilling through the block on the scored line & using a
bolster and club hammer to split them out ... seems like a lot of effort
and will still kick out a surpising amount of dust.