The Natural Philosopher wrote:

I think they are the same - that small one looks exactly like what I have.

Thanks. Does a 6mm core drill need a central pilot bit? Nothing seems to
be included in that Amazon listing. I'll check elsewhere.

On 23/03/2021 23:49, Bert Coules wrote:

Can anyone recommend the best really strong and secure hollow-wall
fixings for use through tiles?

Shows the limitations
https://www.youtube.com/watch?v=lHb-Tcvkn7M


maybe not suitable for 3 closely spaced screws
https://www.youtube.com/watch?v=aeFyQS2NGVM


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 24/03/2021 19:01, alan_m wrote:

maybe not suitable for 3 closely spaced screws
https://www.youtube.com/watch?v=aeFyQS2NGVM

Near the end other fixings are shown
Also can be used with two screws in a straight line (see towards end of
video)


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

alan_m wrote:

Shows the limitations
https://www.youtube.com/watch?v=lHb-Tcvkn7M

My word, that chap is dedicated. Thanks for that link and the other one.

Those Gee-Fix fittings looks very good but I think you're right: they
wouldn't be ideal for a ring of closely-spaced screws such as I have on the
mounting plates of the grab rails. I haven't watched to the end yet.

The English chap gets extra points, too, for not yelling at me.

In article ,
Bert Coules wrote:
Dave Plowman (News) wrote:

I fitted a vertical one to my shower cubical
fixed into a stud. In
practice, it's OK to use.

In this particular instance that would be possible only on one side of
the enclosure, since the other is half height and topped with glass.

For me, mainly to hang on to while washing one foot at a time.

I think that's exactly the sort of use envisaged: an aid to balance
rather than a quick-grab resort in the event of a possible fall.

Quite - if pretty tottery, a walk in bath would make more sense. Although
a seat in the shower might help too.

My enclosure is quite wide, so a grab rail on the back wall under the
shower head the best compromise.

--
*If you don't pay your exorcist you get repossessed.*

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

On 24/03/2021 06:07, The Natural Philosopher wrote:



IN the case of a grab handle that will only be experiencing very strong
vertical loads,

Unless you have already used them to stand up and then slip sideways on
a slippery shower or bath floor whilst still holding on to the rail.
Grab rails are not only installed to help with removing yourself from,
say, a bath but also to provide a means of support whilst stepping out
of a shower tray. In a friends rented house a previous occupant had
installed grab rails to help them get off the toilet - Installed on a
wall facing the toilet seat. In this case all the force would have been
in the horizontal direction.


--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 24/03/2021 18:51, Bert Coules wrote:
The Natural Philosopher wrote:

I think they are the same - that small one looks exactly like what I
have.

Thanks.Â* Does a 6mm core drill need a central pilot bit?Â* Nothing seems
to be included in that Amazon listing.Â* I'll check elsewhere.

No. And therein lies the problem. They wander like buggery until you get
them started, then they stay in the groove

One way to sort that is to make a 6mm hole in something and use that as
a jig pressed against the wall.

Or a steady hand and very light pressure to get the hole started.


--
All political activity makes complete sense once the proposition that
all government is basically a self-legalising protection racket, is
fully understood.

On 24/03/2021 19:18, alan_m wrote:
On 24/03/2021 06:07, The Natural Philosopher wrote:



IN the case of a grab handle that will only be experiencing very
strong vertical loads,

Unless you have already used them to stand up and then slip sideways on
a slippery shower or bath floor whilst still holding on to the rail.
Grab rails are not only installed to help with removing yourself from,
say, a bath but also to provide a means of support whilst stepping out
of a shower tray.Â* In a friends rented house a previous occupant had
installed grab rails to help them get off the toiletÂ* - Installed on a
wall facing the toilet seat.Â* In this case all the force would have been
in the horizontal direction.


But not full body weight.




--
Outside of a dog, a book is a man's best friend. Inside of a dog it's
too dark to read.

Groucho Marx

The Natural Philosopher wrote:

No. And therein lies the problem. They wander like buggery until you get
them started, then they stay in the groove

One way to sort that is to make a 6mm hole in something and use that as a
jig pressed against the wall.

I've been Googling this. With the larger sizes the recommended technique
appears to be to approach the surface at a 45 degree angle, let the drill
bite in just one spot, and then slowly move it to 90 degrees with the whole
of the drill in contact.

Maybe the old trick of putting masking tape or similar on the glazed surface
would help?

I might see if I can find a scrap tile or two to practise on - but not too
much, to avoid blunting the drill.

Thanks for the info.

On Wed, 24 Mar 2021 17:09:47 +0000, The Natural Philosopher
wrote:


On 24/03/2021 16:02, Bert Coules wrote:

Dave Plowman (News) wrote:


I fitted a vertical one to my shower cubical
fixed into a stud. In
practice, it's OK to use.


In this particular instance that would be possible only on one side of
the enclosure, since the other is half height and topped with glass.


For me, mainly to hang on to while washing one
foot at a time.


I think that's exactly the sort of use envisaged: an aid to balance
rather than a quick-grab resort in the event of a possible fall.



I got a bit interested in this and went looking for the strength of tiles.

It looks like even crappy roof style tiles are around 10,000 psi for
pure compressive loading

Assuming te full weight of a human is going to end up on a surface are
of say 1/4" thick by 1/4" rawlplug diameter that's one sixteenth of
square inch so the stress of say a 15st hulk (210lb) at 3,360 psi is
not going to break the tile
What that means is that you can stand on a 1/4" square piece of metal on
a tile and not break it if its supported from below, and that actual
compressions strength on a properly grouted wall is simply not a problem.

The obvious failure mode is that you pull laterally and the whole
plasterboard wall collapses. Because that is plasterboard covered in
tiles in TENSION.

and its about ten times weaker in tension, but again that tension will
be spread out over the entire height of the wall, not 1/4" square.

Could a man support his weight on - say a horizontal batten screwed to a
bit of 400mm wide plasterboard, fastened with plasterboard screws to a
couple of studs?

I think he could, especially if covered in tiles.

In the end its a rather nasty version of a centre loaded end supported
beam, of rather broad width.

the failure mode here would be the plasterboard giving way along a grout
line.

Now the formula for a beam failure is that the tensile load in the face
of the beam where the pull is, should not exceed the tensile strength of
the material, and for a 16" wide bit of plasterboard of say 6" width
1/2" thick, we have approximately 8/.25=64 x 210 / 6 = 2000 psi. which
is above the 300 or so psi that plasterboard can handle.

What does THIS mean. It means you cant support a 15 stone man on a 6"
wide strip of plasterboard ceiling on 400mm studs no matter what the
attachment is.

Its doubtful even on an infinite width.

So the engineering problem is now what sort of attachment, but whether
or not the wall itself can stand the load under ANY sort of attachment

It is absolutely clear that a vertical load is AOK. the plasterboard and
ceramic composite is well able to handle the load and the tiles will
spread the stress concentration of a rawlplug just fine. What is now at
issue is how much lateral load can the wall take before it tears off the
studs and how likely a person grabbing for a handle would actually exter
in that direction.

Her wqe can consider the reverse case - -a person falling AGAINST a
plasterboard wall - will it break? My experience says it wont. That you
need a club hammer to punch a hole in a plasterboard wall, leaning or
falling against it is not enough .

What is the conclusion?

The first conclusion is that the type of fixing is irrelevant. Once the
wall is tiled it has sufficient strength due to the tile to handle any
sort of fixing, and my experience shows that whilst a plasterboard wall
is crap at taking a rawlplug, a tiled wall is brilliant.

The second conclusion is that the plasterboard wall itself - not the
fixing area - but the whole wall, is the weak spot from a lateral load.
You wont pull the rawlplugs out but you might *just* pull down the whole
wall section between the studs if you really really grabbed hard, or
jerked on it while falling

I think its *really unlikely*, but if it bothers you the ONLY solution
is to reinforce the plasterboard at that point and since that means
going in behind it, you might as well add a noggin.

Personally I simply would not bother.

Especially since there is generally a horizontal noggin about halfway up
a stud wall where you should be able to fix to it, or near it. That
changes the stress equations dramatically The beam equations that apply
are no longer 400mm load in middle supported at the ends, but a much
shorter - the vertical distance to the noggin - end supported cantilever.


If you have such you dont need to fasten into it, just near it, and the
job is done

You should be able to ID studs and noggins by tapping on the back side
of the wall.


I don't see anything about the spacing of the bar from the wall in
your calculation. Any weight on the bar exerts a torque to bend its
way off the wall.
--
Dave W

In article ,
Bert Coules wrote:
No. And therein lies the problem. They wander like buggery until you get
them started, then they stay in the groove

One way to sort that is to make a 6mm hole in something and use that as a
jig pressed against the wall.

I've been Googling this. With the larger sizes the recommended technique
appears to be to approach the surface at a 45 degree angle, let the drill
bite in just one spot, and then slowly move it to 90 degrees with the whole
of the drill in contact.

Maybe the old trick of putting masking tape or similar on the glazed surface
would help?

I might see if I can find a scrap tile or two to practise on - but not too
much, to avoid blunting the drill.

Thanks for the info.

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

--
*Depression is merely anger without enthusiasm *

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

On 24/03/2021 23:42, Dave W wrote:
On Wed, 24 Mar 2021 17:09:47 +0000, The Natural Philosopher
wrote:

On 24/03/2021 16:02, Bert Coules wrote:
Dave Plowman (News) wrote:

I fitted a vertical one to my shower cubical
fixed into a stud. In
practice, it's OK to use.

In this particular instance that would be possible only on one side of
the enclosure, since the other is half height and topped with glass.

For me, mainly to hang on to while washing one
foot at a time.

I think that's exactly the sort of use envisaged: an aid to balance
rather than a quick-grab resort in the event of a possible fall.


I got a bit interested in this and went looking for the strength of tiles.

It looks like even crappy roof style tiles are around 10,000 psi for
pure compressive loading

Assuming te full weight of a human is going to end up on a surface are
of say 1/4" thick by 1/4" rawlplug diameter that's one sixteenth of
square inch so the stress of say a 15st hulk (210lb) at 3,360 psi is
not going to break the tile
What that means is that you can stand on a 1/4" square piece of metal on
a tile and not break it if its supported from below, and that actual
compressions strength on a properly grouted wall is simply not a problem.

The obvious failure mode is that you pull laterally and the whole
plasterboard wall collapses. Because that is plasterboard covered in
tiles in TENSION.

and its about ten times weaker in tension, but again that tension will
be spread out over the entire height of the wall, not 1/4" square.

Could a man support his weight on - say a horizontal batten screwed to a
bit of 400mm wide plasterboard, fastened with plasterboard screws to a
couple of studs?

I think he could, especially if covered in tiles.

In the end its a rather nasty version of a centre loaded end supported
beam, of rather broad width.

the failure mode here would be the plasterboard giving way along a grout
line.

Now the formula for a beam failure is that the tensile load in the face
of the beam where the pull is, should not exceed the tensile strength of
the material, and for a 16" wide bit of plasterboard of say 6" width
1/2" thick, we have approximately 8/.25=64 x 210 / 6 = 2000 psi. which
is above the 300 or so psi that plasterboard can handle.

What does THIS mean. It means you cant support a 15 stone man on a 6"
wide strip of plasterboard ceiling on 400mm studs no matter what the
attachment is.

Its doubtful even on an infinite width.

So the engineering problem is now what sort of attachment, but whether
or not the wall itself can stand the load under ANY sort of attachment

It is absolutely clear that a vertical load is AOK. the plasterboard and
ceramic composite is well able to handle the load and the tiles will
spread the stress concentration of a rawlplug just fine. What is now at
issue is how much lateral load can the wall take before it tears off the
studs and how likely a person grabbing for a handle would actually exter
in that direction.

Her wqe can consider the reverse case - -a person falling AGAINST a
plasterboard wall - will it break? My experience says it wont. That you
need a club hammer to punch a hole in a plasterboard wall, leaning or
falling against it is not enough .

What is the conclusion?

The first conclusion is that the type of fixing is irrelevant. Once the
wall is tiled it has sufficient strength due to the tile to handle any
sort of fixing, and my experience shows that whilst a plasterboard wall
is crap at taking a rawlplug, a tiled wall is brilliant.

The second conclusion is that the plasterboard wall itself - not the
fixing area - but the whole wall, is the weak spot from a lateral load.
You wont pull the rawlplugs out but you might *just* pull down the whole
wall section between the studs if you really really grabbed hard, or
jerked on it while falling

I think its *really unlikely*, but if it bothers you the ONLY solution
is to reinforce the plasterboard at that point and since that means
going in behind it, you might as well add a noggin.

Personally I simply would not bother.

Especially since there is generally a horizontal noggin about halfway up
a stud wall where you should be able to fix to it, or near it. That
changes the stress equations dramatically The beam equations that apply
are no longer 400mm load in middle supported at the ends, but a much
shorter - the vertical distance to the noggin - end supported cantilever.


If you have such you dont need to fasten into it, just near it, and the
job is done

You should be able to ID studs and noggins by tapping on the back side
of the wall.

I don't see anything about the spacing of the bar from the wall in
your calculation. Any weight on the bar exerts a torque to bend its
way off the wall.


yes, but that force will be exerted on the top screws and will be the
same whether its mounted on brick or tiles. If the brick case works -
i.e. the plug doesn't pull out - then so too will the tiles.



--
"I guess a rattlesnake ain't risponsible fer bein' a rattlesnake, but ah
puts mah heel on um jess the same if'n I catches him around mah chillun".

On Wed, 24 Mar 2021 15:35:20 -0000, "Bert Coules"
wrote:


Dave Plowman (News) wrote:


If you have access to the other side, remove a bit of that plasterboard
and fit a decent noggin between the studs, and fix through the tiles to
that.


This does seem to be a popular suggestion, so thanks.


I've juat had another idea, although a bit ugly.

Basically it increases the size of the rail mountings to spread the
loads. Use sheet metal screws to attach each flange to the underside
of a metal dinner plate. Fix each plate to the wall using three screws
into wallplugs in the plasterboard, two at the top and one at the
bottom.

If the rail is grabbed in a fall, the sudden inertial force could well
make the total force even greater than the person's weight. The total
force will exert a torque tending to pull the top screws out and press
the plate in at the bottom. But because the plates are so much larger
than the original flanges the in-out forces will be proportionally
less. Also each screw has its own area of wall to stress, unlike the
original clustered arrangement.

The plates could either be the same colour as the rail or painted to
match the tiles.
--
Dave W

On 24/03/2021 20:41, The Natural Philosopher wrote:
On 24/03/2021 18:51, Bert Coules wrote:
The Natural Philosopher wrote:

I think they are the same - that small one looks exactly like what I
have.

Thanks.Â* Does a 6mm core drill need a central pilot bit?Â* Nothing
seems to be included in that Amazon listing.Â* I'll check elsewhere.

No. And therein lies the problem. They wander like buggery until you get
them started, then they stay in the groove

One way to sort that is to make a 6mm hole in something and use that as
a jig pressed against the wall.

Or a steady hand and very light pressure to get the hole started.



A technique I use is to use a tile drill bit to drill a hole in the tile.

Once through the tile, I then switch to a different drill bit to suit
the material underneath the tile.

I usually use the next size up diameter for the tile so that the 2nd
drill bit used to drill whats underneath the tile does not catch on the
hol within the tile.

On Thu, 25 Mar 2021 00:37:17 +0000 (GMT), Dave Plowman (News) wrote:

In article ,
Bert Coules wrote:
No. And therein lies the problem. They wander like buggery until you get
them started, then they stay in the groove

One way to sort that is to make a 6mm hole in something and use that as a
jig pressed against the wall.

I've been Googling this. With the larger sizes the recommended technique
appears to be to approach the surface at a 45 degree angle, let the drill
bite in just one spot, and then slowly move it to 90 degrees with the whole
of the drill in contact.

Maybe the old trick of putting masking tape or similar on the glazed surface
would help?

I might see if I can find a scrap tile or two to practise on - but not too
much, to avoid blunting the drill.

Thanks for the info.

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

I found two ways of doing this:
use a wheel brace with a smallish bit - for tiles a small spade bit made for
tiles is ideal - and 'rock' the wheel. Because it doesn't do more than about
a quarter of a turn it doesn't 'walk'.
use a spade bit and 'rock' it by hand - I managed to put a 6mm bit through
(B&Q basic) a tile using the bit with finger and thumb once through the
glaze.
No tape or anything else needed.
--
Peter.
The gods will stay away
whilst religions hold sway

In article ,
PeterC wrote:
Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

I found two ways of doing this: use a wheel brace with a smallish bit -
for tiles a small spade bit made for tiles is ideal - and 'rock' the
wheel. Because it doesn't do more than about a quarter of a turn it
doesn't 'walk'. use a spade bit and 'rock' it by hand - I managed to put
a 6mm bit through (B&Q basic) a tile using the bit with finger and thumb
once through the glaze. No tape or anything else needed.


Yes - those spade tile drills have a very sharp point and don't wander
anything like a more conventional drill.

I find just giving the back of the drill a thump (with it stationary)
enough to give it a pilot. If you have a fairly steady hand.

--
*Never test the depth of the water with both feet.*

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

SH wrote:

I usually use the next size up diameter for the tile so that the 2nd drill
bit used to drill what's underneath the tile does not catch on the hole
within the tile.

I can see the sense in that, so thanks. But in my case - as advised here -
I need the wall plug to be a close fit to the hole in the tile to ensure a
good grip when it expands.

Dave Plowman (News) wrote:

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

Since the surface of the tile immediately around the fixing holes will be
covered by the base of the mounting brackets for the grab rail, I have
wondered about trying to scratch off the glaze where the holes have to go in
order to provide better grip for the drill bit. Something to try on my test
tile.

PeterC wrote:

Use a wheel brace with a smallish bit - for tiles a small spade bit made
for
tiles is ideal - and 'rock' the wheel. Because it doesn't do more than
about
a quarter of a turn it doesn't 'walk'.

Interesting thought, thanks.

Dave W wrote:

I've just had another idea, although a bit ugly.

Yes, just a bit. It could look good given suitable surrounding decor but
not, alas, in my case. Nice thought though.

On 26/03/2021 11:26, Bert Coules wrote:
SH wrote:

I usually use the next size up diameter for the tile so that the 2nd
drill bit used to drill what's underneath the tile does not catch on
the hole within the tile.

I can see the sense in that, so thanks.Â* But in my case - as advised
here - I need the wall plug to be a close fit to the hole in the tile to
ensure a good grip when it expands.

IME there is absolutely NO grip to the plasterboard at all. SH's method
is intelligent for e.g tiled MDF, but in terms of tiled plasterboard you
are attaching to a tile that spreads the load to the plasterboard and
other tiles.


--
Theres a mighty big difference between good, sound reasons and reasons
that sound good.

Burton Hillis (William Vaughn, American columnist)

On 26/03/2021 11:29, Bert Coules wrote:
Dave Plowman (News) wrote:

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

Since the surface of the tile immediately around the fixing holes will
be covered by the base of the mounting brackets for the grab rail, I
have wondered about trying to scratch off the glaze where the holes have
to go in order to provide better grip for the drill bit.Â* Something to
try on my test tile.

the core drill will wander all over the place and do that...;-)

I think the ONLY thing that worked for me was a bit of MDF with a 6mm
hole in it.


--
Theres a mighty big difference between good, sound reasons and reasons
that sound good.

Burton Hillis (William Vaughn, American columnist)

The Natural Philosopher wrote:

I think the ONLY thing that worked for me was
a bit of MDF with a 6mm hole in it.

How did you hold it in place?

I've been experimenting on a spare tile and using the start-at-an-angle
technique I've successfully drilled a 6mm and an 8mm hole with very little
chipping around the perimeter. But drilling two holes in a tile clamped
horizontally in a Workmate in a room with with lots of space to move around
is presumably rather different to drilling ten holes in a vertical tiled
wall while standing in a shower enclosure.

One thing that I do now know: when the core drills broke completely through
the tile, the drill slammed forward and the face of the chuck met the tile
with some force. There was nothing behind it, where in the actual job there
will be plasterboard (which should make a slight difference, maybe), and no
damage to the tile resulted, but it's still something to be wary of.

Tomorrow I tackle the actual work...

On 26/03/2021 18:14, Bert Coules wrote:
The Natural Philosopher wrote:

I think the ONLY thing that worked for me was
a bit of MDF with a 6mm hole in it.

How did you hold it in place?

wiv me ovver hand...

I've been experimenting on a spare tile and using the start-at-an-angle
technique I've successfully drilled a 6mm and an 8mm hole with very
little chipping around the perimeter.Â* But drilling two holes in a tile
clamped horizontally in a Workmate in aÂ* room with with lots of space to
move around is presumably rather different to drilling ten holes in a
vertical tiled wall while standing in a shower enclosure.

One thing that I do now know: when the core drills broke completely
through the tile, the drill slammed forward and the face of the chuck
met the tile with some force.Â* There was nothing behind it, where in the
actual job there will be plasterboard (which should make a slight
difference, maybe), and no damage to the tile resulted, but it's still
something to be wary of.

Tomorrow I tackle the actual work...




--
€œThe fundamental cause of the trouble in the modern world today is that
the stupid are cocksure while the intelligent are full of doubt."

- Bertrand Russell

The Natural Philosopher wrote:

wiv me ovver hand...

I rather suspected that might be the case. I would have thought that the
MDF would be prone to slipping about on the tiles, but clearly you managed
to stop it doing so. I might try another test tomorrow.

Thanks.

On 26/03/2021 11:29, Bert Coules wrote:
Dave Plowman (News) wrote:

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

Since the surface of the tile immediately around the fixing holes will
be covered by the base of the mounting brackets for the grab rail, I
have wondered about trying to scratch off the glaze where the holes have
to go in order to provide better grip for the drill bit.Â* Something to
try on my test tile.


Be careful that the scratch doesn't extend beyond the diameter of the
hole or it could be the starting point for stress crack in future.

--
mailto : news {at} admac {dot} myzen {dot} co {dot} uk

On 26/03/2021 11:29, Bert Coules wrote:
Dave Plowman (News) wrote:

Masking tape can work - starting out with a small drill. Or if you have
one of those old tile scorers - the sort you use before snapping them.
Just used to break the glaze.

Since the surface of the tile immediately around the fixing holes will
be covered by the base of the mounting brackets for the grab rail, I
have wondered about trying to scratch off the glaze where the holes have
to go in order to provide better grip for the drill bit.Â* Something to
try on my test tile.

I've successfully drilled tiles for plugs by just using the tip of a
tungsten tile cutter to scratch a small hole in the glaze and then
drilling with a standard masonry bit.

John M

John M & Alan_m, thanks.

On 26/03/2021 18:36, Bert Coules wrote:
The Natural Philosopher wrote:

wiv me ovver hand...

I rather suspected that might be the case.Â* I would have thought that
the MDF would be prone to slipping about on the tiles, but clearly you
managed to stop it doing so.Â* I might try another test tomorrow.

Push harder. Or glue a rubber sheet on the back - a million ways to
increase friction...

Thanks.



--
When plunder becomes a way of life for a group of men in a society, over
the course of time they create for themselves a legal system that
authorizes it and a moral code that glorifies it.

Frédéric Bastiat

The Natural Philosopher wrote:

Push harder. Or glue a rubber sheet on the back - a million ways to
increase friction...

If the first hole doesn't go well today, I'll try your MDF approach; thanks
for the tip.

On 26 Mar 2021 at 13:39:06 GMT, "The Natural Philosopher"
wrote:

On 26/03/2021 11:26, Bert Coules wrote:
SH wrote:

I usually use the next size up diameter for the tile so that the 2nd
drill bit used to drill what's underneath the tile does not catch on
the hole within the tile.

I can see the sense in that, so thanks.Â* But in my case - as advised
here - I need the wall plug to be a close fit to the hole in the tile to
ensure a good grip when it expands.

IME there is absolutely NO grip to the plasterboard at all. SH's method
is intelligent for e.g tiled MDF, but in terms of tiled plasterboard you
are attaching to a tile that spreads the load to the plasterboard and
other tiles.

In which case, don't use a traditional wood screw with an unthreaded shank,
especially one on the large side for the plug. Use constant diameter
fully-threaded screws. Otherwise you can apply huge forces to crack the tile
as the screw goes fully in. DAMHIKT

--
Roger Hayter

Job done:

https://ibb.co/bbzfgX5

Many thanks to everyone who helped. In the end, the advice to use a
diamond-tipped core drill, start the hole at an angle to break through the
glaze in one spot, and then slowly bring the drill upright was invaluable:
doing it that way I had hardly any slipping and none at all outside the area
to be concealed by the bracket covers.

With a bit of fiddling of the final position I was able to secure each of
the brackets with three screws into timber and only two into wall plugs: the
result feels to me to be very secure indeed.

So thanks again.

On 27/03/2021 13:46, Bert Coules wrote:
Job done:

https://ibb.co/bbzfgX5

Many thanks to everyone who helped.Â* In the end, the advice to use a
diamond-tipped core drill,Â* start the hole at an angle to break through
the glaze in one spot, and then slowly bring the drill upright was
invaluable: doing it that way I had hardly any slipping and none at all
outside the area to be concealed by the bracket covers.

With a bit of fiddling of the final position I was able to secure each
of the brackets with three screws into timber and only two into wall
plugs: the result feels to me to be very secure indeed.

So thanks again.
Well done m8.

classic "research, test, if good, implement"


--
Religion is regarded by the common people as true, by the wise as
foolish, and by the rulers as useful.

(Seneca the Younger, 65 AD)

The Natural Philosopher wrote:

Well done m8.

Thanks. Your help was much appreciated.

Bert Coules wrote

Job done:

https://ibb.co/bbzfgX5

We need a video of you hurling yourself against it and it surviving that :-(

Preferably not naked, there are clearly children reading in here.

Many thanks to everyone who helped. In the end, the advice to use a
diamond-tipped core drill, start the hole at an angle to break through
the glaze in one spot, and then slowly bring the drill upright was
invaluable: doing it that way I had hardly any slipping and none at all
outside the area to be concealed by the bracket covers.

Thanks for the washup, not done often enough imo.

With a bit of fiddling of the final position I was able to secure each of
the brackets with three screws into timber and only two into wall plugs:
the result feels to me to be very secure indeed.

We still need the real test.

So thanks again.

On Sun, 28 Mar 2021 06:45:16 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH more of the trolling senile asshole's latest troll**** unread

--
Richard addressing senile Rodent Speed:
"**** you're thick/pathetic excuse for a troll."
MID:

Rod Speed wrote:

We still need the real test.

Where do you think any possible weakness would lie? Suppose someone did
slip and grab the rail, putting the whole of their weight against it,
vertically,horizontally or at an angle: what might happen? The woodscrews
be pulled out of the timber battens? The entire half-height stud wall give
way? The rail itself break?

I'm not saying that any of these outcomes is an impossibility, simply trying
to understand just what the possible danger might be.

Thanks.

Bert Coules wrote
Rod Speed wrote

We still need the real test.

Where do you think any possible weakness would lie?

Basically the full weight of a massively obese person
falling on the bar vertically, pushing it down with the
lever action of the short horizontal legs to the wall.

Suppose someone did slip and grab the rail, putting the whole of their
weight against it, vertically,
horizontally or at an angle: what might happen?

The plugs thru the tiles pull out with the top screws
with the bottom of the round plate with the screws
thru it acting as a hinge against the tile.

The woodscrews be pulled out of the timber battens?

Did you manage to get all of them into timber battens ?

I thought you said that that was only possible at one end ?

The entire half-height stud wall give way?

That's possible but less likely.

The rail itself break?

Shouldn't happen if it was designed properly.

I'm not saying that any of these outcomes is an impossibility, simply
trying to understand just what the possible danger might be.

The first one imo, particularly if all the screws don't go into timber
battens.

On Sun, 28 Mar 2021 09:24:18 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:



Basically the

Basically you are a SOCIOPATHIC trolling piece of senile ****!

--
Sqwertz to Rodent Speed:
"This is just a hunch, but I'm betting you're kinda an argumentative
asshole.
MID: