Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

Rory wrote:
Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

If you use plastic plugs there is enough flexibility to have margin for
error.
Or glue the mirror and then epoxy the covering caps on to pretend you
screwed it.

On Jun 23, 9:43*am, Rory wrote:
Is there a trick to this?

I had to put up a drilled mirror last night. *It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. *Removed mirror and drilled other holes. *I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . *Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

At least you can polyfill the holes and redrill next day


NT

Rory coughed up some electrons that declared:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

If you find out, let me know!

Anyway - one option may be to overdrill the incorrect holes to about 10mm,
plug with dowell so it's tight with a drop of glue, then put mirro screws
into that.

HTH

Tim

Tim S wrote:
Rory coughed up some electrons that declared:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

If you find out, let me know!

Anyway - one option may be to overdrill the incorrect holes to about 10mm,
plug with dowell so it's tight with a drop of glue, then put mirro screws
into that.

or overdrill and put in car body filler, mark points with matchstick,
and then screw in after its almost set.

HTH

Tim

On 23 June, 09:48, The Natural Philosopher
wrote:

If you use plastic plugs there is enough flexibility to have margin for
error.

This is a mirror - which implies the use of mirror screws with dome
caps, which then look dreadful if they're inserted at even a slight
angle.
Although the flexibility of plastic plugs might be sufficient to let
you insert a screw off-angle and hold the mirror up, it's not a good
way to do it for neatness

What I'd do is first of all to drill the holes accurately: mark them
from the mirror, not by measuring. Then drill them with an SDS drill
and copious surplus power rather than struggling with a weak hammer
drill that will follow mortar courses. Use a very low power to start
the hole though, so that it doesn't wander initially.

With a hole that's off centre, then first check that the hole is big
enough to allow the screw to go into it, and perpendicular, without
needing to put it in off-angle. If the hole isn't, then drill it
bigger (up to about 1/2" - anything more and you're better re-drilling
another, maybe smaller). Don't be tempted to polyfilla it up and try
again, that's too soft and it wil lead the drill back into the old
hole. If you _must_ do this, at least use a fairly hard mortar mix.

Now your problem is an oversized, but well placed, hole. Use a plug
in hee, but make it either carved wood, or else use a resin or putty
plugging compound. The old asbestos fibre Rawlplug compound was one
solution, nowadays Fisher sell (Screwfix) some papery disks that you
wet before use and then poke down the hole. Bit pricey for regular
use, but they're great for getting you out of a jam. If it's high
load, then of course there's polyester resin kits.

On 23 June, 11:46, Andy Dingley wrote:
On 23 June, 09:48, The Natural Philosopher
wrote:

If you use plastic plugs there is enough flexibility to have margin for
error.

This is a mirror - which implies the use of mirror screws with dome
caps, which then look dreadful if they're inserted at even a slight
angle.
Although the flexibility of plastic plugs might be sufficient to let
you insert a screw off-angle and hold the mirror up, it's not a good
way to do it for neatness

Thanks for your other comments too. I did get the screws in, but was
terrified of stressing the mirror and breaking it.

On 23 June, 11:46, Andy Dingley wrote:

This is a mirror - which implies the use of mirror screws with dome
caps, which then look dreadful if they're inserted at even a slight
angle.
Although the flexibility of plastic plugs might be sufficient to let
you insert a screw off-angle and hold the mirror up, it's not a good
way to do it for neatness

Thnaks for your other comments too.
I did get the screws in, but was concerned about stressing the mirror
and breaking it.

In uk.d-i-y, Rory wrote:
I marked through the
other holes. Removed mirror and drilled other holes.

After marking through the holes (small circle) and removing the mirror,
draw a large (1" or so) cross over the spot. Then if the drill wanders
during those crucial first few revolutions, you can spot it and drag it
back on line.

--
Mike Barnes

On 23 June, 11:38, The Natural Philosopher
wrote:
or overdrill and put in car body filler, mark points with matchstick,
and then screw in after its almost set.

While doing it I did think something like that would be ideal! Drill
holes about an inch in diameter and fill them with a sausage of some
plasticky type of stuff that you could just screw into.


I also learned that brick dust is a bu**er to get off grout, even if
the grout has been in place for a week. I thought it would just
vacuum up, but it didn't. Mrs R was still cleaning it at 11PM -
that's teach her for making me do stuff during the week.

On Tue, 23 Jun 2009 01:43:03 -0700, Rory wrote:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course, but
the holes are exactly 1.5" in from each edge, which made measuring the
holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the other
holes.
Removed mirror and drilled other holes. I used a 3mm pilot drill to
try
to start the hole in the right place and then 6mm masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

=========================================

You can improve success rate by centre punching as if drilling metal, but
it will take longer. Remove a circle of plaster (about 1" diameter - just
enough to see clearly) and mark the hole position on the brick face.
Centre punch the mark using either a proper centre punch or a 6" nail. Now
using your smallest bit (1/8") drill the hole directly into the brick /
block. Open up the hole to take a plug and fix the mirror to this hole.
Use the same technique (centre punch / drill) to mark each hole in turn
directly into brick. When all holes are correctly drilled put a plug and
screw into each hole (without mirror) and make good the plaster with
Polyfilla.

If this still doesn't work, drill oversize holes and insert solid wooden
plugs to take the screws.

--
==========================================
Using Ubuntu Linux
Windows shown the door
==========================================

Cicero wrote:

You can improve success rate by centre punching as if drilling metal, but
it will take longer. Remove a circle of plaster (about 1" diameter - just
enough to see clearly) and mark the hole position on the brick face.
Centre punch the mark using either a proper centre punch or a 6" nail. Now
using your smallest bit (1/8") drill the hole directly into the brick /
block. Open up the hole to take a plug and fix the mirror to this hole.
Use the same technique (centre punch / drill) to mark each hole in turn
directly into brick. When all holes are correctly drilled put a plug and
screw into each hole (without mirror) and make good the plaster with
Polyfilla.

Does anyone else have the problem that Sod's law says that wherever you
place the mirror one screw will be on a brick / mortar interface and is
therefore guaranteed to be out of alignment?

Andrew

In article ,
Andrew May wrote:
Does anyone else have the problem that Sod's law says that wherever you
place the mirror one screw will be on a brick / mortar interface and is
therefore guaranteed to be out of alignment?

Guaranteed to happen with everything that needs a secure fixing -
especially rads. Luckily with those you can use a rawlbolt which will grip
between the two courses. But overkill for a mirror. ;-)
What's needed is a mortar finder that works through plaster - like a stud
finder. Only more accurate. ;-)

--
*What am I? Flypaper for freaks!?

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

On Tue, 23 Jun 2009 01:43:03 -0700 (PDT)
Rory wrote:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

Start with a very small drill, not the size required. Use low power
until the drill is at least 1/2 inch into the brick (not the plaster).

Small drills break easily, take extra care.

If the holes line up, fine, drill out with the right size. If not do
not be tempted to fill with polyfiller and redrill. Poly filler is so
soft the drill will wander to it. The best thing is to drill oversize,
so that the required hole will be in the oversize, then fill with
polyfiller and redrill.

Or move to a house with wooden walls?

R.

On Tue, 23 Jun 2009 13:05:17 +0100
"Dave Plowman (News)" wrote:

What's needed is a mortar finder that works through plaster - like a stud
finder. Only more accurate. ;-)



Should be possible to make an echo sounder to do that. Hmmmm?

On Tue, 23 Jun 2009 01:43:03 -0700, Rory wrote:

Is there a trick to this?

I've found sometimes it's useful to make a quick template out of
thick metal with holes in the right place and of the right width for a
drill bit, and then drill small pilot holes - then take the template off
and enlarge to the right size using a different bit.

(At some point maybe I'll get my act together and make some sort of
pivoting adjustable template so I can set holes at different spacings.)

Wherever I can I use permanent brackets for things, though - it's a lot
easier to drill the wall, make a bracket to fit the holes, then add the
attachment points so that the thing being attached sits square (the only
problem with that route being that it's hard to make things sit completely
flush with the wall, but that's not always an issue)

cheers

Jules

Rory wrote:


I also learned that brick dust is a bu**er to get off grout, even if
the grout has been in place for a week.

If I'm doing light masonry drilling then I use my left hand to hold a
little piece of folded card underneath the drill bit to catch all the
dust. For heavier drilling where I need both hands, the spouse holds the
vacuum cleaner pipe just underneath the drilling. Both techniques work
well. You can get fancy attachments for drills to suck the dust, but
they are expensive. As you say, sometimes the brick dust can be a pain
to clean off some surfaces.

--
David in Normandy.
To e-mail you must include the password FROG on the
subject line, or it will be automatically deleted
by a filter and not reach my inbox.

Andrew May wrote:


Does anyone else have the problem that Sod's law says that wherever you
place the mirror one screw will be on a brick / mortar interface and is
therefore guaranteed to be out of alignment?


Similar problems with my house walls which are made of stone. The inner
walls are more accurately described as rubble with a "mortar" consisting
of clay. Some of the rocks are sandstone and others are granite. Pot
luck when drilling what you hit. Generally, when fixing up wooden
battens to the walls I attempt to drill twice as many holes as I need as
half will fail due to hitting "nothing" ie big soft lump of crumbly
clay, or solid granite.

--
David in Normandy.
To e-mail you must include the password FROG on the
subject line, or it will be automatically deleted
by a filter and not reach my inbox.

"Rory" wrote in message
...
Is there a trick to this?



I've found that using my DeWalt SDS drill that you can be very accurate with
drilling, largely because of the varispeed function, eg dill starts off very
slowly and gradually increasing the speed. That is when the hammer action
automatically cuts in.
Only one thing that still bugs me is that you can't see through the plaster
and you can still hit the edge of a brick and it goes off line into the
mortar. I suppose the only way then is to move the object and drill
somewhere near-by and Pollyfill the original hole/s..
Wavey Dave

In uk.d-i-y, David in Normandy wrote:
Rory wrote:

I also learned that brick dust is a bu**er to get off grout, even if
the grout has been in place for a week.

If I'm doing light masonry drilling then I use my left hand to hold a
little piece of folded card underneath the drill bit to catch all the
dust. For heavier drilling where I need both hands, the spouse holds
the vacuum cleaner pipe just underneath the drilling. Both techniques
work well. You can get fancy attachments for drills to suck the dust,
but they are expensive. As you say, sometimes the brick dust can be a
pain to clean off some surfaces.

Indeed. I usually get an envelope out of the recycling, tear off the
flap, open it out a bit, and masking-tape it to the wall just below the
hole.

--
Mike Barnes

On 23 June, 12:36, Cicero wrote:

You can improve success rate by centre punching as if drilling metal, but
it will take longer. Remove a circle of plaster (about 1" diameter - just
enough to see clearly) and mark the hole position on the brick face.

Thanks for the overall idea - there would be some benefit in being
able to see what you're drilling into, but it strikes me that trying
to mark the holes to the accuracy required for mirror screws wouldn't
be easy due to the plaster thickness.

I did drill pilot holes with a 3mm drill anyway, but something's still
not right.

I've put mirrors up a few times in the past and can't remember having
this much difficulty - I think that perhaps I was just in the wrong
frame of mind!

On Tue, 23 Jun 2009 01:43:03 -0700 (PDT), Rory
wrote:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

If it is into thick plaster you may be lucky and get perfect holes. I
have a ruler with guides for making the job easy.

If you drill very oversize holes and then fill with plaster you can
then drill accurate holes when it sets, or even push the plugs into
the wet plaster to set insitue.

EricP wrote:
On Tue, 23 Jun 2009 01:43:03 -0700 (PDT), Rory
wrote:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes. I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

If it is into thick plaster you may be lucky and get perfect holes. I
have a ruler with guides for making the job easy.

If you drill very oversize holes and then fill with plaster you can
then drill accurate holes when it sets, or even push the plugs into
the wet plaster to set insitue.

or you could get a foot or two of pallet wood,
cut a hole in the plaster for it,
nail and screw the wood into the wall
(trying a few times until you get a good joint)
then screw the mirror into the wood
(the wood will be hidden behind the mirror,
and gaps can be polyfilled,
(I use plaster cement cos its cheaper and harder)

[g]

"David in Normandy" wrote in message
...
Rory wrote:


I also learned that brick dust is a bu**er to get off grout, even if
the grout has been in place for a week.

If I'm doing light masonry drilling then I use my left hand to hold a
little piece of folded card underneath the drill bit to catch all the
dust. For heavier drilling where I need both hands, the spouse holds the
vacuum cleaner pipe just underneath the drilling. Both techniques work
well. You can get fancy attachments for drills to suck the dust, but they
are expensive. As you say, sometimes the brick dust can be a pain to clean
off some surfaces.


I've found that masking an A4 bit of paper along its length on the wall and
then bending the opposite end nearly back on to its self and affix with
masking tape going the opposite way works great. Both hands are then free
and it collects ALL the dust.

I was looking for something to show it online as I'm sure that's where I got
the tip from.

Similar to this
http://www.instructables.com/id/Make...in-30-seconds/
but only 1 sheet of paper folded over is what I mean.

In article ,
EricP wrote:
If you drill very oversize holes and then fill with plaster you can
then drill accurate holes when it sets, or even push the plugs into
the wet plaster to set insitue.

Better to use quick set cement.

--
*A bartender is just a pharmacist with a limited inventory *

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

Dave Plowman (News) wrote:
In article ,
EricP wrote:
If you drill very oversize holes and then fill with plaster you can
then drill accurate holes when it sets, or even push the plugs into
the wet plaster to set insitue.

Better to use quick set cement.


Body filler is faster, so you can simply fill the hole and re-drill 10
minutes later. I think Halfords is the cheapest retail outlet. 1.75 kgs
for under a tenner. Can't imagine life without it

Rory wrote:
Is there a trick to this?

Problem I face on a daily basis. I'd love to meet the pratts who design
these things.

I had to put up a drilled mirror last night. It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

Quite common to have the holes at something like 58.5 cm apart, just to make
it difficult to divide & measure, when they could be 60 cm apart & make life
easy.


So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. Removed mirror and drilled other holes.

Exactly what I do to make sure things are level & holes in right place.

I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

Good question. As I said the pratts who design these things should be shot.
It is very difficult indeed to get spot on accurate holes in masonry.

A few things I've found - Bosch multi material drills
http://www.screwfix.com/prods/26900/...-Bit-6-x-100mm
have a much sharper point than a normal masonry bit, so its much easier to
get started in the right place.

Second, I don't use the hammer action until I have too, seems to help.
Third, plugs with a 'lip' have silghtly more tolerance.


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

Mike Barnes wrote:
In uk.d-i-y, David in Normandy wrote:
Rory wrote:

I also learned that brick dust is a bu**er to get off grout, even
if the grout has been in place for a week.

If I'm doing light masonry drilling then I use my left hand to hold a
little piece of folded card underneath the drill bit to catch all the
dust. For heavier drilling where I need both hands, the spouse holds
the vacuum cleaner pipe just underneath the drilling. Both techniques
work well. You can get fancy attachments for drills to suck the dust,
but they are expensive. As you say, sometimes the brick dust can be a
pain to clean off some surfaces.

Indeed. I usually get an envelope out of the recycling, tear off the
flap, open it out a bit, and masking-tape it to the wall just below
the hole.

Yup, thats the way to go. I carry envelopes & tape in the drill driver bag!


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

Steven Campbell wrote:
"David in Normandy" wrote in message
...
Rory wrote:


I also learned that brick dust is a bu**er to get off grout, even if
the grout has been in place for a week.

If I'm doing light masonry drilling then I use my left hand to hold a
little piece of folded card underneath the drill bit to catch all the
dust. For heavier drilling where I need both hands, the spouse holds
the vacuum cleaner pipe just underneath the drilling. Both
techniques work well. You can get fancy attachments for drills to
suck the dust, but they are expensive. As you say, sometimes the
brick dust can be a pain to clean off some surfaces.


I've found that masking an A4 bit of paper along its length on the
wall and then bending the opposite end nearly back on to its self and
affix with masking tape going the opposite way works great. Both
hands are then free and it collects ALL the dust.

I was looking for something to show it online as I'm sure that's
where I got the tip from.

I saw the envelope thing on a Tommy Walsh show ages ago.


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

On 23 June, 19:03, "The Medway Handyman"
wrote:

A few things I've found - Bosch multi material drillshttp://www.screwfix.com/prods/26900/Drill-Bits/Masonry-Drill-Bits/Mul...

They looks good - will buy one, or maybe a set, next visit to
Screwfix. The reviews on the Screwfix site are pretty effusive!

Second, I don't use the hammer action until I have too, seems to help.

Same here.

Third, plugs with a 'lip' have silghtly more tolerance.

I've suddenly remembered seeing wall plugs with the hole offset - you
rotated them to align the hole. Did I dream that or do they actually
exist?

On Tue, 23 Jun 2009 09:11:29 -0700, Rory wrote:

On 23 June, 12:36, Cicero wrote:

You can improve success rate by centre punching as if drilling metal,
but it will take longer. Remove a circle of plaster (about 1" diameter -
just enough to see clearly) and mark the hole position on the brick
face.

Thanks for the overall idea - there would be some benefit in being able to
see what you're drilling into, but it strikes me that trying to mark the
holes to the accuracy required for mirror screws wouldn't be easy due to
the plaster thickness.

I did drill pilot holes with a 3mm drill anyway, but something's still not
right.

I've put mirrors up a few times in the past and can't remember having this
much difficulty - I think that perhaps I was just in the wrong frame of
mind!

=========================================

If you're doing a lot of mirrors you might invest in a special jig.
There's a whole range of them available, all of which I'd forgotten
about because I use mine for other purposes. Wolfcraft do two different
types for wood (but probably also suitable for mirror fixing accuracy)
and a tile drilling jig which would also do the same job.

See www.machinemart.co.uk for the Wolfcraft and for the tile drilling
jigs. Axminster also do a similar type of jig to the Wolfcraft type and
Lidl do a tiling jig, but it might be differently described.

Cic.

--
==========================================
Using Ubuntu Linux
Windows shown the door
==========================================

On Tue, 23 Jun 2009 12:11:34 -0700, Rory wrote:
I've suddenly remembered seeing wall plugs with the hole offset - you
rotated them to align the hole. Did I dream that or do they actually
exist?

Hmm, that triggered a memory, although the ones I saw were for
plasterboard, not brick, and took a particular standard bolt thread (I
don't recall what, now) - they weren't for screws.

On 23 June, 09:43, Rory wrote:
Is there a trick to this?

I had to put up a drilled mirror last night. *It's metric of course,
but the holes are exactly 1.5" in from each edge, which made measuring
the holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the
other holes. *Removed mirror and drilled other holes. *I used a 3mm
pilot drill to try to start the hole in the right place and then 6mm
masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . *Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?


Another way is to drill the hole as usual and then user a bigger drill
to open up the outermost 10mm or so of the hole. Put the plug to the
back - beyond the opened up bit. Do not fill or replaster. Then
there's some lateral adjustment possible as you tighten the screw.

Robert

On 23 June, 20:38, RobertL wrote:

Another way is to drill the hole as usual and then user a bigger drill
to open up the outermost 10mm or so of the hole. *Put the plug to the
back - beyond the opened up bit. *Do not fill or replaster. *Then
there's some lateral adjustment possible as you tighten the screw.

That would be OK on something like batten or shelf bracket, but a bit
dodgy with a mirror - it would be stressed the screw tried to
straighten. Also, there really needs to be support against the back of
the mirror to keep the top-hat washer in place.

On Tue, 23 Jun 2009 14:14:43 -0700 (PDT), Rory
had this to say:

On 23 June, 20:38, RobertL wrote:

Another way is to drill the hole as usual and then user a bigger drill
to open up the outermost 10mm or so of the hole. *Put the plug to the
back - beyond the opened up bit. *Do not fill or replaster. *Then
there's some lateral adjustment possible as you tighten the screw.

That would be OK on something like batten or shelf bracket, but a bit
dodgy with a mirror - it would be stressed the screw tried to
straighten. Also, there really needs to be support against the back of
the mirror to keep the top-hat washer in place.

For something like a mirror, I'd be tempted to attach a plywood board
to the wall, then screw the mirror to that.
Fitting such a backboard to a wall would be a lot easier than the
mirror.

--
Frank Erskine

Frank Erskine coughed up some electrons that declared:

On Tue, 23 Jun 2009 14:14:43 -0700 (PDT), Rory
had this to say:

On 23 June, 20:38, RobertL wrote:

Another way is to drill the hole as usual and then user a bigger drill
to open up the outermost 10mm or so of the hole. *Put the plug to the
back - beyond the opened up bit. *Do not fill or replaster. *Then
there's some lateral adjustment possible as you tighten the screw.

That would be OK on something like batten or shelf bracket, but a bit
dodgy with a mirror - it would be stressed the screw tried to
straighten. Also, there really needs to be support against the back of
the mirror to keep the top-hat washer in place.

For something like a mirror, I'd be tempted to attach a plywood board
to the wall, then screw the mirror to that.
Fitting such a backboard to a wall would be a lot easier than the
mirror.


I've done something similar in my plumbing cupboard - vertical battens every
2 foot - much eaiser to clip pipes to wood in quantity than farting around
with plugs

On Tue, 23 Jun 2009 11:36:32 GMT, Cicero
wrote:

On Tue, 23 Jun 2009 01:43:03 -0700, Rory wrote:

Is there a trick to this?

I had to put up a drilled mirror last night. It's metric of course, but
the holes are exactly 1.5" in from each edge, which made measuring the
holes from the centre line difficult.

So I did the first hole (top right hole and put the mirror in place.
Then holding it and checking it was vertical, I marked through the other
holes.
Removed mirror and drilled other holes. I used a 3mm pilot drill to
try
to start the hole in the right place and then 6mm masonry.

Put the plugs in but a couple of the holes are half the hole diameter
out. . Of course, with a drilled mirror, and the washers used,
there's absolutely no margin for error - how on earth are you supposed
to drill holes in masonary with complete accuracy?

=========================================

You can improve success rate by centre punching as if drilling metal, but
it will take longer. Remove a circle of plaster (about 1" diameter - just
enough to see clearly) and mark the hole position on the brick face.
Centre punch the mark using either a proper centre punch or a 6" nail.

I find that this is where the old fashioned Rawdrill comes in handy
and I always start off in plaster with it. Mark up, line up the
Rawdrill with the mark, one hard whack with the hammer to take it
through the plaster, then a couple more whacks to start the hole in
the base. then use a masonry drill to finish off.

Now
using your smallest bit (1/8") drill the hole directly into the brick /
block. Open up the hole to take a plug and fix the mirror to this hole.
Use the same technique (centre punch / drill) to mark each hole in turn
directly into brick. When all holes are correctly drilled put a plug and
screw into each hole (without mirror) and make good the plaster with
Polyfilla.

If this still doesn't work, drill oversize holes and insert solid wooden
plugs to take the screws.