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.

"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

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 09:01:47 +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.

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 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!

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.

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 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.

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.

On Fri, 04 Sep 2009 23:43:15 +0100, John Rumm
wrote:

Sounds like the end got snagged on a stone or something - or perhaps it
lost its carbide edge on one side and hence started drilling unevenly.

That's exactly what happened. A brand new, never used, drill bit went
into the wall, and when it came out the carbide edge was only present
on one side. It was a Bosch bit too, so I had expected better.

I remember trying to drill small holes in a concrete floor so that I
could screw carpet grips into yellow plugs. I used Bosch bit for that
and it melted! Perhaps I was too heavy handed that time too? But my
experience with this limited number of Bosch bits has not been
positive; perhaps they are just rebadged? I've used the cheapest
Toolstation bits without problems. YMMV etc.

On Sat, 05 Sep 2009 15:35:15 +0100, John Rumm
wrote:

So if the hole is straight, a pipe would also go through it... The only
problem you then have is if you want to have a pipe lead straight up or
down to it, and you would hence need a 87 degree elbow or similar.

Yes, I was able to pass the pipe through but the fitting was not flush
with the wall; it was at an angle.

On Sat, 05 Sep 2009 15:42:19 +0100, John Rumm
wrote:

Sounds like you need the more traditional:

http://www.toolstation.com/shop/Plum.../sd2697/p74070

That way the pipe can come out the wall at any angle, and the turn into
the *side* of the fitting with the aid of an elbow.

Thanks. I thought I was saving myself some work by using one fitting
instead of two but it backfired.

I have seen he above fitting before but where the pipe was fitted
externally. I had not thought that I could use an elbow to rotate the
pipe through the wall into the side of it. How clever!

Thanks.

On Sat, 05 Sep 2009 15:35:15 +0100, John Rumm
wrote:

you would hence need a 87 degree elbow or similar.

Sorry, I forgot to ask, does such a thing exist as a non-90 degree
elbow. I'm sure it doesn't but I thought I should ask. I've only ever
seen 90 and 45 degree (or should that be 135) fittings.

On Fri, 04 Sep 2009 23:43:15 +0100, John Rumm
wrote:

to illustrate just how much flexibility there
is in a drill bit:

http://wiki.diyfaq.org.uk/index.php?...:Drillflex.jpg
http://wiki.diyfaq.org.uk/index.php?...Drillflex2.jpg

Thanks for taking the trouble to upload these. The bits feel quite
rigid in my hands so this was an eye opener. BTW what do you use the
14Lb weight for normally?

Stephen wrote:
On Fri, 04 Sep 2009 23:43:15 +0100, John Rumm
wrote:

to illustrate just how much flexibility there
is in a drill bit:

http://wiki.diyfaq.org.uk/index.php?...:Drillflex.jpg
http://wiki.diyfaq.org.uk/index.php?...Drillflex2.jpg

Thanks for taking the trouble to upload these. The bits feel quite
rigid in my hands so this was an eye opener. BTW what do you use the
14Lb weight for normally?

Stretching his member?

Dave

I've got me coat.

On Mon, 07 Sep 2009 23:51:12 +0100, John Rumm
wrote:

If you are running a pipe vertically to the hole, you can put a slight
bend in the end of it. So it tips the elbow dwn a bit and gives you the
87 degrees or whatever it is you need.

That's a clever trick; I will remember that in case I need it in the
future. I thought you were meaning a brass elbow that was 87 degrees!

On Mon, 07 Sep 2009 23:55:28 +0100, John Rumm
wrote:

If you get a bit hot enough the weld will fail that holds the carbide
edge. Did the bit change colour or start to get a blue sheen? If it did
that would indicate overheating.

No, it didn't overheat nor turn blue.

The Bosch ones I use regularly are their "multimaterial" bits which I
find to be excellent - they in theory drill everything, but are
excellent on masonry.

I have used those in a non-sds drill but I thought they only went up
to about 13 or 14mm and in short lengths. I didn't know they did wide
and long sizes too. This was just a "plain" Bosch sds bit.

On Mon, 07 Sep 2009 23:57:49 +0100, John Rumm
wrote:

Its quite handy when you want to weight something down - say when
assembling and gluing stuff. Or the other day I was jigsawing round the
edge of a board, and the weight was quite handy for holding the board on
the table while I worked on the edge overhanging the table.

They sound handy. I'll have to check local skips

On Thu, 10 Sep 2009 14:55:03 +0100, John Rumm
wrote:

No, they don't do large versions of those that I am aware of. I was just
mentioning it to say that some at least of the bosch bits are very good.
Not tried their SDS ones.

Toolstation sell Bosch sds bits called "Bosch B8". They look as though
they have a blue flute, as do the multipurpose bits but I don't know
whether B8 is the Bosch code for multipurpose or whether it is
something else all together.

In article ,
John Rumm wrote:
No, they don't do large versions of those that I am aware of. I was just
mentioning it to say that some at least of the bosch bits are very good.
Not tried their SDS ones.

I've got SDS bits from many sources - including market stalls - and they
don't seem to vary by much. Unlike 'ordinary' masonry drills.

--
*If you think this van is dirty, you should try having sex with the driver*

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