Hello,

I tried to drill a hole through a 500mm concrete wall yesterday. I was
hoping to put a 15mm copper pipe through to an outdoor tap (you may
remember my other thread about the old pipe freezing and bursting).

I was unsuccessful. I used an sds drill and I got through the wall
quick enough but although I (thought I) held the drill level, the exit
hole and the entry hole were at two different heights and passing a
pipe through was impossible.

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

How can I prevent this in the future? I drilled from one side straight
through. Should I have carefully marked each side and drilled from
each side, hopefully meeting halfway?

For drilling though brick I have used a 16mm bit for 15mm pipe in the
past. Do I need to use something bigger than 16mm in concrete to allow
for it not being straight?

I was using a 6kg Titan drill I got from Screwfix some time ago.
Despite being a budget model it has served me well. I had a Bosch
drill bit in it. I had not used the drill bit before and I won't be
using it again as the end broke. I had expected better longevity from
a branded bit. Are the clutches on sds drills like those on cars, i.e.
do they wear out eventually? I ask because mine worked once or twice
yesterday ;(

Thanks,
Stephen.

Stephen wrote:

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

Yes. I used to drill deep through-holes in steel. It was rare for the
drill to stay square to the bed for more than 8 inches.It could be half
an inch out on a foot long hole. That is in steel, which is a pretty
consisitent structure thoughout. Concrete has all sorts of holes and
stones in it to deflect drills, so it would be unlikely to get a true,
straight, level hole through such a length.

How can I prevent this in the future? I drilled from one side straight
through. Should I have carefully marked each side and drilled from
each side, hopefully meeting halfway?

For drilling though brick I have used a 16mm bit for 15mm pipe in the
past. Do I need to use something bigger than 16mm in concrete to allow
for it not being straight?

Yes. 20mm would be suitable for 15mm pipe, maybe even 22mm.
Alan.
--
To reply by e-mail, change the ' + ' to 'plus'.

Stephen wrote:

I tried to drill a hole through a 500mm concrete wall yesterday. I was
hoping to put a 15mm copper pipe through to an outdoor tap

I was unsuccessful. I used an sds drill and I got through the wall
quick enough but although I (thought I) held the drill level, the exit
hole and the entry hole were at two different heights and passing a
pipe through was impossible.

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

If you try to pass the drill back through the hole, does it still
go? Can you pass a stiff but flexible wire through the hole?

It is possible that a fragment of the concrete that was disturbed
during the drilling has now dropped and is obstructing the hole.

Chris
--
Chris J Dixon Nottingham UK


Have dancing shoes, will ceilidh.

On Fri, 04 Sep 2009 08:32:13 GMT, Chris J Dixon
wrote:

If you try to pass the drill back through the hole, does it still
go? Can you pass a stiff but flexible wire through the hole?

It is possible that a fragment of the concrete that was disturbed
during the drilling has now dropped and is obstructing the hole.

You can pass the drill through the hole, in fact you can see through
the hole, so the hole is clear, it's just that it slopes an inch/two
inches downward!

"Stephen" wrote in message
...
Hello,

I tried to drill a hole through a 500mm concrete wall yesterday. I was
hoping to put a 15mm copper pipe through to an outdoor tap (you may
remember my other thread about the old pipe freezing and bursting).

I was unsuccessful. I used an sds drill and I got through the wall
quick enough but although I (thought I) held the drill level, the exit
hole and the entry hole were at two different heights and passing a
pipe through was impossible.

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

How can I prevent this in the future? I drilled from one side straight
through. Should I have carefully marked each side and drilled from
each side, hopefully meeting halfway?

For drilling though brick I have used a 16mm bit for 15mm pipe in the
past. Do I need to use something bigger than 16mm in concrete to allow
for it not being straight?

I was using a 6kg Titan drill I got from Screwfix some time ago.
Despite being a budget model it has served me well. I had a Bosch
drill bit in it. I had not used the drill bit before and I won't be
using it again as the end broke. I had expected better longevity from
a branded bit. Are the clutches on sds drills like those on cars, i.e.
do they wear out eventually? I ask because mine worked once or twice
yesterday ;(

Thanks,
Stephen.

Use plastic pipe rather than copper

On Fri, 4 Sep 2009 09:39:57 +0100, "slider" wrote:

Use plastic pipe rather than copper

That would have worked but I was trying to use this wall plate that
had an integral copper tube:

http://www.toolstation.com/shop/Plum.../sd2696/p33291

If you had used a plastic pipe, how would you have secured the tap to
the wall?

That said, I don't know how good the wall plate above would have been.
I think the three screw holes would have been too close to the hole I
had made for the pipe and I may not have been able to secure it.

In article ,
Stephen wrote:
I tried to drill a hole through a 500mm concrete wall yesterday. I was
hoping to put a 15mm copper pipe through to an outdoor tap (you may
remember my other thread about the old pipe freezing and bursting).

I was unsuccessful. I used an sds drill and I got through the wall
quick enough but although I (thought I) held the drill level, the exit
hole and the entry hole were at two different heights and passing a
pipe through was impossible.

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

Don't think they're *that* flexible. Did you try drilling through again
from the other side? And moving the drill in slowly? Concrete has 'stones'
in it which can deflect the cutting part of the drill enough to cause a
less than perfect hole.

I'd tend to use a drill quite a bit larger than the pipe and sleeve it
with PVC where it passes through the wall - you can get clip on sleeves
designed to pretty up radiator tails which work fine.

--
*Sticks and stones may break my bones but whips and chains excite me*

Dave Plowman London SW
To e-mail, change noise into sound.

On Fri, 04 Sep 2009 09:42:14 +0100
"Dave Plowman (News)" wrote:

In article ,
Stephen wrote:
I tried to drill a hole through a 500mm concrete wall yesterday. I was
snip

I'd tend to use a drill quite a bit larger than the pipe and sleeve it
with PVC where it passes through the wall - you can get clip on sleeves
designed to pretty up radiator tails which work fine.



Me too. I use WC solvent-weld overflow pipe (22mm OD/19mm ID).
I've also used it to put radiator tails in a stud wall - as a conduit.
Useful stuff, and dead cheap.

R.

On Fri, 04 Sep 2009 09:42:14 +0100, "Dave Plowman (News)"
wrote:

Did you try drilling through again from the other side?

Yes, and it came out somewhere else on the other side. I had a wall
that looked like cheese, it was a complete disaster!

I'd tend to use a drill quite a bit larger than the pipe and sleeve it
with PVC where it passes through the wall

I was going to use overflow pipe to sleeve it but never got that far.

On Fri, 04 Sep 2009 09:01:47 +0100, Stephen wrote:

I had not used the drill bit before and I won't be using it again as the
end broke. I had expected better longevity from a branded bit. Are the
clutches on sds drills like those on cars, i.e. do they wear out
eventually? I ask because mine worked once or twice yesterday ;(

Sounds like you were over loading the drilling system. You don't need
to lean on a SDS drill like you do an conventional hammer drill. The
SDS action does the "leaning" for you. All you need to do is keep the
drill bit reasonably, but not hard, against the bottom of the hole
and let the SDS action do the cutting work. Enough pressure so that
the bit isn't bouncing about on the bottom of the hole.

Leaning on the drill, particulary with a long bit, is going to make
it flex/bend and deflect off harder bits in the wall rather than
drill through them.

It's probably asking a bit much to get a 15mm pipe through a 16mm
hole as well. As others have pointed out it really ought to be
sleeved. Cement and copper don't get on...

--
Cheers
Dave.

On Fri, 04 Sep 2009 15:50:15 +0100 (BST), "Dave Liquorice"
wrote:

Leaning on the drill, particulary with a long bit, is going to make
it flex/bend and deflect off harder bits in the wall rather than
drill through them.

Perhaps that was my mistake then. I don't remember consciously leaning
on the drill but I guess I must have done without realising it.
Perhaps it is an old habit from the old days of pre-sds drills? I
haven't had any trouble before but then again, I haven't done a deep
sds hole before now.

It's probably asking a bit much to get a 15mm pipe through a 16mm
hole as well. As others have pointed out it really ought to be
sleeved. Cement and copper don't get on...

I think I have used 16mm holes in wood and brick to pass pipes through
but for concrete it clearly doesn't work.

I know cement and copper have been discussed on the group before but I
didn't think there was any consensus whether they corroded or not. I
seem to remember people arguing both sides. I was thinking of lining
it more for protection so the copper did not get scratched on the
jagged edges of the concrete.

Our house was built with copper CH pipes buried in the concrete floor.
I thought this was wasteful as it was heating the concrete, not the
radiators. The 30 year old copper pipe was black. Is that a sign of
corrosion? But it certainly was not leaking and it was 30 years old.

Stephen used his keyboard to write :
Hello,

I tried to drill a hole through a 500mm concrete wall yesterday. I was
hoping to put a 15mm copper pipe through to an outdoor tap (you may
remember my other thread about the old pipe freezing and bursting).

I was unsuccessful. I used an sds drill and I got through the wall
quick enough but although I (thought I) held the drill level, the exit
hole and the entry hole were at two different heights and passing a
pipe through was impossible.

Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

How can I prevent this in the future? I drilled from one side straight
through. Should I have carefully marked each side and drilled from
each side, hopefully meeting halfway?

For drilling though brick I have used a 16mm bit for 15mm pipe in the
past. Do I need to use something bigger than 16mm in concrete to allow
for it not being straight?

The hole diameter needed to be larger, as others have said to allow the
pipe to be sleeved and to give the clearance to be able to get your
pipe through. Something like a round bit of wood with an out facing
pointy end, put in the pipe end - would help to align the pipe to the
second part of the hole.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

In article ,
Stephen wrote:
Now that I know from the "one metre drill bits at Aldi" thread that
these bits are flexible, is it possible that the bit deflected inside
the wall?

Possible - but then the pipe would bend as easily.

--
*"I am " is reportedly the shortest sentence in the English language. *

Dave Plowman London SW
To e-mail, change noise into sound.

On Fri, 04 Sep 2009 23:47:02 +0100, Dave Plowman (News) wrote:

... is it possible that the bit deflected inside the wall?

Possible - but then the pipe would bend as easily.

15mm tube is far more ridged than a 16mm drill. The drill is also far
more likely to drill a hole with a kink in it(*) rather than a smooth
and even bend. A hole with a kink requires the bend in the tube to
move along the tube as you (try to) put it through the hole.

You'll get away with a small deflection but not much more than a few
mm in every 300 or so.

--
Cheers
Dave.