Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil

On Mon, 23 Apr 2007 14:43:40 +0100, "TheScullster"
wrote:

Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil



Eeeeewww !!! You did say you were refurbing the toilet didn't you .?
:-)

In article ,
TheScullster wrote:

Just puzzled by the shape of my 1970s cistern. I am re-furbing a
downstairs toilet and noticed that the existing cistern has a
kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

Our 1970 Twyford's has the same cutout in the back
wall, but more or less in the centre. Don't know
what it's there for though.

--
Tony Williams.

Manufacturing feature? Something that helps during the kiln firing?

"Stuart B" wrote


Eeeeewww !!! You did say you were refurbing the toilet didn't you .?
:-)

Don't worry Stuart, since that pic was taken, the cistern has been
demounted, bleached out and all the old internals stripped.
The syphon was a solid and serious piece of kit. Far more rhobust than the
modern offerings.

Phil

On Mon, 23 Apr 2007 15:00:43 +0100, Tony Williams
wrote:

In article ,
TheScullster wrote:

Just puzzled by the shape of my 1970s cistern. I am re-furbing a
downstairs toilet and noticed that the existing cistern has a
kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

Our 1970 Twyford's has the same cutout in the back
wall, but more or less in the centre. Don't know
what it's there for though.

And my old Armitage Shanks ??

Andy

"TheScullster" wrote in message
...
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil


It's so the overflow can be taken straight out the back if desired
(althgough no-one ever bothers!)


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

"Bob Mannix" wrote in message
...

"TheScullster" wrote in message
...
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil


It's so the overflow can be taken straight out the back if desired
(althgough no-one ever bothers!)

I withdraw that remark as it's stupid! Too late in the afternoon. One feels
it's for a pipe of some sort though.


--
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

On Mon, 23 Apr 2007 15:48:52 +0100, Andy Cap
wrote:

On Mon, 23 Apr 2007 15:00:43 +0100, Tony Williams
wrote:

In article ,
TheScullster wrote:

Just puzzled by the shape of my 1970s cistern. I am re-furbing a
downstairs toilet and noticed that the existing cistern has a
kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

Our 1970 Twyford's has the same cutout in the back
wall, but more or less in the centre. Don't know
what it's there for though.

And my old Armitage Shanks ??

The same on my fairly recent Armitage Shanks.. :-)

--
Frank Erskine

"Bob Mannix" wrote in message
...

"Bob Mannix" wrote in message
...

"TheScullster" wrote in message
...
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing
cistern has a kind of curved cut-out in the back at the top left hand
side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil


It's so the overflow can be taken straight out the back if desired
(althgough no-one ever bothers!)

I withdraw that remark as it's stupid! Too late in the afternoon. One
feels it's for a pipe of some sort though.


--

I think it is the 'last chance' overflow. My Alia has a similar feature.
Presumably if the overflow (Warning Pipe) is blocked it will cause the water
to overspill down the back on the off chance this might be preferable to
spilling all around the lid. It will also limit the weight the cystern may
have to hold.
Bob Mannix
(anti-spam is as easy as 1-2-3 - not)

"Bob Mannix" wrote in message
...

"Bob Mannix" wrote in message
...

"TheScullster" wrote in message
...
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing
cistern has a kind of curved cut-out in the back at the top left hand
side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil


It's so the overflow can be taken straight out the back if desired
(althgough no-one ever bothers!)

I withdraw that remark as it's stupid! Too late in the afternoon. One
feels it's for a pipe of some sort though.

I would agree until I popped the lid off my cistern to have a look. Mine has
the curved cut out along the central 2/3rds of the lid, too big to be for a
pipe.

Adam

"TheScullster" wrote in message
...
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil




Probably curved inwards to allow for crap plastering/tiling behind it
causing a high spot, which when mounting screws are tightened would cause
said cistern to break its back.

In article ,
"John" writes:
I think it is the 'last chance' overflow. My Alia has a similar feature.
Presumably if the overflow (Warning Pipe) is blocked it will cause the water
to overspill down the back on the off chance this might be preferable to
spilling all around the lid.

and even more importantly, prevents the lid floating on a
full-to-the-brim cistern and possibly slipping off.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

On Mon, 23 Apr 2007 14:43:40 +0100, TheScullster wrote:

Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?


I have assumed that these recesses were to allow air to enter the cistern
during flushing. On some models the lid fits pretty well and without this
opening the flush could be seriously reduced by the partial vacuum during
flushing.






--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he http://www.makewrite.demon.co.uk/GasFittingStandards

On Mon, 23 Apr 2007 22:08:07 +0000 (UTC), Ed Sirett
wrote:

On Mon, 23 Apr 2007 14:43:40 +0100, TheScullster wrote:

Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?


I have assumed that these recesses were to allow air to enter the cistern
during flushing. On some models the lid fits pretty well and without this
opening the flush could be seriously reduced by the partial vacuum during
flushing.

I don't think plastic cisterns have such a cutout; have they?
Some plastic ones have a lid which is attached by screws and must be
even more airtight.

--
Frank Erskine
"Automatic door - push button to operate"

"Ed Sirett" wrote in message
...
On Mon, 23 Apr 2007 14:43:40 +0100, TheScullster wrote:

Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?


I have assumed that these recesses were to allow air to enter the cistern
during flushing. On some models the lid fits pretty well and without this
opening the flush could be seriously reduced by the partial vacuum during
flushing.

I have no idea what the cutout is for but wouldn't the air enter through
the overflow pipe when flushing and exhaust again when filling as it does
on plastic cisterns with screw down lids?

Tony

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html
Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html
Gas Fitting Standards Docs he
http://www.makewrite.demon.co.uk/GasFittingStandards

In article ,
Ed Sirett wrote:

I have assumed that these recesses were to allow air to enter
the cistern during flushing. On some models the lid fits pretty
well and without this opening the flush could be seriously
reduced by the partial vacuum during flushing.

That sounds like a very good reason.

I can't see the back, but looking up from the
bottom of the cistern there also seems to be
some sort of a shallow channel up to the cutout.

--
Tony Williams.

In message ,
TheScullster writes
Hi all

Just puzzled by the shape of my 1970s cistern.
I am re-furbing a downstairs toilet and noticed that the existing cistern
has a kind of curved cut-out in the back at the top left hand side.
This can be clearly seen in the picture below:

http://home.freeuk.com/thesculls/Cistern-Plan.JPG

There is no corresponding protrusion in the lid to cover this.

Anyone got any idea what the purpose of this profile might be?

TIA

Phil



My Villeroy & Bosch cistern has this and it's used for bringing a hidden
pipe (buried in the wall) into the cistern. There's a stop valve
attached to the in-wall pipe with the filling mechanism hanging on it.
--
Regards
Phil Morris