Hi All,

I had a quick look at the wall chaser, the 32mm oval conduit, the roll
of ,5m T&E and the metal boxes that I'm supposed to be playing with to
halp my mate over the weekend and have some questions.

First some observations:

The oval is due to carry some 2.5mm down from above the false ceiling
line, to double sockets avove the worktop and back up again (in
several places) to become the 'ring'.

The wall chaser has a maximum slot width of 28mm.

The conduit he has is 32mm wide (but can be swapped out).

Looking at the section of the trunking and the 'knock outs' in metal
box it's sorta square peg / round hole(s) thing?

Q's

So, should we use 25mm wide trunking (plastered in the wall) for two
runs of 2.5mm T&E and (if enough room etc) and which of the 4 holes in
the top of the box would *you* bring the cables into (for a std double
socket) and why please?

Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

I dare say the sparks will (should) know all this when he comes to do
the main hook-up / testing etc but I'd like to make sure the
background stuff is as right as it can be please?

All the best ..

T i m

On Thu, 19 Jan 2006 18:56:10 GMT,it is alleged that T i m
spake thusly in uk.d-i-y:

*prepares to answer by donning flameproof suit* g

Hi All,

I had a quick look at the wall chaser, the 32mm oval conduit, the roll
of ,5m T&E and the metal boxes that I'm supposed to be playing with to
halp my mate over the weekend and have some questions.

First some observations:

The oval is due to carry some 2.5mm down from above the false ceiling
line, to double sockets avove the worktop and back up again (in
several places) to become the 'ring'.

The wall chaser has a maximum slot width of 28mm.

The conduit he has is 32mm wide (but can be swapped out).

Looking at the section of the trunking and the 'knock outs' in metal
box it's sorta square peg / round hole(s) thing?

Yes, I always [this is the reason for the flameproof suit] use a pair
of pipe grips to 'round' the oval conduit and just jam it in with a
grommet, never had any pop out yet.

Q's

So, should we use 25mm wide trunking (plastered in the wall) for two
runs of 2.5mm T&E and (if enough room etc) and which of the 4 holes in
the top of the box would *you* bring the cables into (for a std double
socket) and why please?

25mm + 2x 2.5mm T&Es is a little tight but doable.

And whichever box knockout fits

Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

I do, they're cheap enough and useful to have around.

Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

Personally, I don't twist, but sleeve together.


Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

I was always taught not to twist, so I don't. I do however twist the
ENDS of the earth wires simply because it feels more solid, (1.5mm
earths on ring circuits usually if using T&E)

Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

Flexible conduit cable is fine, the right gauge of *flex* may not be
correct though, due to voltage rating. In practice it's not going to
matter - especially on an earth - but it could fail an inspection.

I dare say the sparks will (should) know all this when he comes to do
the main hook-up / testing etc but I'd like to make sure the
background stuff is as right as it can be please?

All the best ..

T i m







--
You cannot shake hands with a clenched fist.
- Indira Gandhi

On Thu, 19 Jan 2006 20:45:57 +0000, Owain
wrote:

T i m wrote:
So, should we use 25mm wide trunking (plastered in the wall) for two
runs of 2.5mm T&E and (if enough room etc)

I'd run the chaser down the wall twice, bash out the ridge in the
middle, and put in 2 x ovals with a gap between them. Probably more
likely to hold plaster better when you make good.

Hmm .. 'two ovals'. With this chaser I'm gonna have to bash out the
ridge left between the blades anyway and if it's as dusty a job as you
guys suggest I think one pass will be sufficient thanks! As long as I
can get (easily / legally) 2 x 2.5mm T&E's up/down a ~1.5m length of
25mm oval I think I'll go with that.

and which of the 4 holes in
the top of the box would *you* bring the cables into (for a std double
socket) and why please?

The ones up to which you abut the ends of the ovals. That's probably
going to be the middle pair.

lol . I was thinking there might be an advantage say bringing the
cables in at the end rather than near the middle as they cables may
lay better in the box or summat?

Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

Of course :-)

Good ;-)

Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

If the cables were coming through the same box hole the earths might be
sleevable as one, but as you'll be using separate holes and 2.5mm
probably better sleeving separately.

Ok. But even if run side-by-side would you sleeve the earths
separatly?

Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

I'm a twister. Opinions vary.

"Twisting the wire a-way .. twisting .. twisting .." em .. ar ..
sorry ;-(

Although if you thread the cable through before beginning you might
manage without cutting the conductors at all.

Hmm .. I have done that before and I like the concept .. just a bit
more effort required to get it right.

Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

Yes, flex and cable in the same terminal probably won't hold a firm
connection. Anyway, why buy flex when you'll have plenty of offcuts of
earth from your reel of 2.5mm.

Yep, good point .. noted ;-)

I dare say the sparks will (should) know all this when he comes to do
the main hook-up / testing etc but I'd like to make sure the
background stuff is as right as it can be please?

Do check for continuity end to end and polarity at the sockets before
the sparky comes. Less embarrasing if you find your own faults first.

Indeed. I generally work fairly methodically, checking each move /
step as I go so generally I check for mistakes as I go. Still might do
the test as you suggest though.

Al the best ..

T i m

On Thu, 19 Jan 2006 21:18:29 GMT, Chip
wrote:


Looking at the section of the trunking and the 'knock outs' in metal
box it's sorta square peg / round hole(s) thing?

Yes, I always [this is the reason for the flameproof suit] use a pair
of pipe grips to 'round' the oval conduit and just jam it in with a
grommet, never had any pop out yet.

Hmmm .. imaginitive .. squeese the square peg till it's round! ;-)


Q's

So, should we use 25mm wide trunking (plastered in the wall) for two
runs of 2.5mm T&E and (if enough room etc) and which of the 4 holes in
the top of the box would *you* bring the cables into (for a std double
socket) and why please?

25mm + 2x 2.5mm T&Es is a little tight but doable.

Well, of course there would be more room in 32mm oval but there's that
conflict at the box? Seems silly to then take both T&E's into one
grommeted hole but I don't think it's wide enough to get one leg
through two holes?

And whichever box knockout fits

ok lol ;-)

Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

I do, they're cheap enough and useful to have around.

Ok .. good ..

Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

Personally, I don't twist, but sleeve together.

Ok .. understood. With the 'double sleeving' solution wouldn't there
be more chance of some exposed earth core near the end of the outer
sheath whereas individually sleeving would allow the sleeving down
between the L / N cores and into the outer sheath?

Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

I was always taught not to twist, so I don't. I do however twist the
ENDS of the earth wires simply because it feels more solid, (1.5mm
earths on ring circuits usually if using T&E)

Understood

Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

Flexible conduit cable is fine,

As in 'singles' ?

the right gauge of *flex* may not be
correct though, due to voltage rating. In practice it's not going to
matter - especially on an earth - but it could fail an inspection.

Are you suggesting it *should* be flex Chip (ie *not* solid) ?

All the best and thanks for the input ..

T i m

In message , T i m
writes
Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

I am no sparky, so do check this for yourself. I was recently informed
that the grommets are a building regs issue.

I have no idea how true that is and I am a little surprised that the
usual posters on this group who have copies of the regs in front of them
haven't already replied to it.

Maybe it's a mute point?

Personally for the extra fractions of a penny, just put them in.
--
Someone

On Fri, 20 Jan 2006 07:00:07 GMT, somebody
wrote:

In message , T i m
writes
Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

I am no sparky, so do check this for yourself. I was recently informed
that the grommets are a building regs issue.

I have no idea how true that is and I am a little surprised that the
usual posters on this group who have copies of the regs in front of them
haven't already replied to it.

Maybe it's a mute point?

Personally for the extra fractions of a penny, just put them in.

Hi and I agree .. 'hapenth of tar' etc ;-)

A thought that came out of the grommet end was the use of round
plastic trunking?

I believe that interfaces directly with the boxes but not sure how it
would handle 2 x 2.55mm T&E rather than singles?

At least there would be a common section between the trunking and the
box hole and would potentailly just need a narrower (but possibly a
touch deeper) slot in the wall?

All the best ..

T i m

In message , T i m
writes
On Fri, 20 Jan 2006 07:00:07 GMT, somebody
wrote:

In message , T i m
writes
Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).

I am no sparky, so do check this for yourself. I was recently informed
that the grommets are a building regs issue.

I have no idea how true that is and I am a little surprised that the
usual posters on this group who have copies of the regs in front of them
haven't already replied to it.

Maybe it's a mute point?

Personally for the extra fractions of a penny, just put them in.

Hi and I agree .. 'hapenth of tar' etc ;-)

A thought that came out of the grommet end was the use of round
plastic trunking?

I believe that interfaces directly with the boxes but not sure how it
would handle 2 x 2.55mm T&E rather than singles?

It should be ok I think.

At least there would be a common section between the trunking and the
box hole and would potentailly just need a narrower (but possibly a
touch deeper) slot in the wall?

It's probably more like double the depth at least of chase required.
Oval conduit is what no more than 10 mm deep? And often oval conduit
will only require the plaster to be chased, rather than the brick or
blockwork as well.

I've never bothered to try to get the ovasl conduit to mate with the
backbox, I just terminate the conduit at the outside edge of the box
--
Chris French

On Fri, 20 Jan 2006 09:40:21 +0000, chris French
wrote:


A thought that came out of the grommet end was the use of round
plastic trunking?

I believe that interfaces directly with the boxes but not sure how it
would handle 2 x 2.55mm T&E rather than singles?

It should be ok I think.

Ok, thanks.

At least there would be a common section between the trunking and the
box hole and would potentailly just need a narrower (but possibly a
touch deeper) slot in the wall?

It's probably more like double the depth at least of chase required.

Ok ..

Oval conduit is what no more than 10 mm deep?

I guess ..

And often oval conduit
will only require the plaster to be chased, rather than the brick or
blockwork as well.

These walls seem to have a very thin skim over a sand cement render of
(as yet) unknown thickness. I'm not too bothered about the depth of
cut as I will be using the wall chaser ;-)

I've never bothered to try to get the ovasl conduit to mate with the
backbox, I just terminate the conduit at the outside edge of the box

Understood Chris .. and by 'terminate' I don't really mean a real
engineering solution, just one where half the oval isn't looking at
some galv steel rather than hole?

Ok, the reason for the conduit there is in the unlikely even you need
to replace the wiring it can be done without tearing slots up the
room. It's just here we have a clean slate, the tools and the chance
(for minor cost differences) to make a 'neat / easy' job of it?

*I* like the mecanical solution where a round pipe enters a round hole
and all sits neat n tidy and I know that is in direct contrast to many
sockets I have come across in the past where you have to rip half the
plaster / wall away around the box to pull the cables though (where
the trunking stops 2" short of the box and the gap filled with render
/ bonding / skim etc?). ;-(

It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the best ..

T i m

T i m wrote:

A thought that came out of the grommet end was the use of round
plastic trunking?

The gromit is just there to protect the wires from the sharp edge of the
box. Thermal expansion etc can result in the box slowly cutting through
the insulation otherwise.

I believe that interfaces directly with the boxes but not sure how it
would handle 2 x 2.55mm T&E rather than singles?

If you are using conduit in wall chases (by no means a requirement - you
can bury directly if desired), it is not a requirement to join it to the
back box. Abutting it ought to be enough. The threadded conduit fixings
to which you refer are more commonly used with exposed conduit when
terminating to surface mounted (often metal clad) accessories.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In message , T i m
writes
On Fri, 20 Jan 2006 09:40:21 +0000, chris French
wrote:

And often oval conduit
will only require the plaster to be chased, rather than the brick or
blockwork as well.

These walls seem to have a very thin skim over a sand cement render of
(as yet) unknown thickness. I'm not too bothered about the depth of
cut as I will be using the wall chaser ;-)

I've never bothered to try to get the ovasl conduit to mate with the
backbox, I just terminate the conduit at the outside edge of the box

Understood Chris .. and by 'terminate' I don't really mean a real
engineering solution, just one where half the oval isn't looking at
some galv steel rather than hole?

That's east enough to arrange, usually I find it lines up ok, if not
little bit of packing does the job.

Ok, the reason for the conduit there is in the unlikely even you need
to replace the wiring it can be done without tearing slots up the
room. It's just here we have a clean slate, the tools and the chance
(for minor cost differences) to make a 'neat / easy' job of it?

I've replaced cables in oval conduit I've put in - as long as it matches
up with the conduit box hole enough so that plaster etc. doesn't hold it
in place.


It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

no, sorry I think that's a load of rubbish :-)

I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the more reason for not over engineering it then....?
--
Chris French

snip

*I* like the mecanical solution where a round pipe enters a round hole
and all sits neat n tidy and I know that is in direct contrast to many
sockets I have come across in the past where you have to rip half the
plaster / wall away around the box to pull the cables though (where
the trunking stops 2" short of the box and the gap filled with render
/ bonding / skim etc?). ;-(

It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the best ..

T i m
Round conduit into round hole on box. I personally found it easier to
feed two TE down the round than the oval.

Do you need to go down and up on each point? Could you chase
horizontally to link some of the sockets and reduce the amount of cable
required and also the joy of getting two pieces of cable down one piece
of conduit.


Paul

In message , Paul
writes
o round hole on box. I personally found it easier to feed two TE down
the round than the oval.

I find it easier justto put in two bits of smller oval conduit than try
to get 2 cables down one bit.
--
Chris French

On Fri, 20 Jan 2006 10:53:48 +0000, chris French
wrote:


Understood Chris .. and by 'terminate' I don't really mean a real
engineering solution, just one where half the oval isn't looking at
some galv steel rather than hole?

That's east enough to arrange, usually I find it lines up ok, if not
little bit of packing does the job.

Ok, understood. Do they make boxes with OVAL knockouts!

Ok, the reason for the conduit there is in the unlikely even you need
to replace the wiring it can be done without tearing slots up the
room. It's just here we have a clean slate, the tools and the chance
(for minor cost differences) to make a 'neat / easy' job of it?

I've replaced cables in oval conduit I've put in - as long as it matches
up with the conduit box hole enough so that plaster etc. doesn't hold it
in place.

Me too .. and then theres that are a pain .. ;-)


It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

no, sorry I think that's a load of rubbish :-)

Oh? From a mechanical point of view I can't see how you could get as
good a bond to the sides of a 10mm deep slot as you could to the sides
of a 20mm deep cut shrug? (I'm not saying there would be an issue
with the former but in my experience it's easier (as in to get the
filler to stay in place) to 'fill' a narrow deep crack than a shallow
wide one?)

I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the more reason for not over engineering it then....?

Good point .. and you are probably right .. sigh ... cept I see it
as 'easier engineering' ...?

1) I find the idea of cutting a 20 x 20 slot (and breaking out the
centre rib) being easier than a 40 x 10 slot and breaking out the
middle to leave it flat and consistant, pleasing.

2) Knowing that my round tubing is mecanically attached to the box and
centered in the hole (and with no rubber grommets falling out) gives
me pleasure.

3) Being able to freely slide the cable through the trunking freely
(as a pair, often easy or one beside the other, often less easy),
rewarding.

4) Knowing that I can access any of it to replace / upgrade / move
later on, satisfying.

But no, I'll do what everyone else does because it's quicker, cheaper
or 'will do', in spite of that fact that none of those give me
satisfaction ..? big sigh

But I can't help it .. I'm a Virgo!

All the best ..

T i m

On Fri, 20 Jan 2006 11:01:29 +0000, Paul wrote:

snip

*I* like the mecanical solution where a round pipe enters a round hole
and all sits neat n tidy and I know that is in direct contrast to many
sockets I have come across in the past where you have to rip half the
plaster / wall away around the box to pull the cables though (where
the trunking stops 2" short of the box and the gap filled with render
/ bonding / skim etc?). ;-(

It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the best ..

T i m
Round conduit into round hole on box.

Don't .. just when I was agreeing with the 'nail it to the surface and
paper over it' boys! ( joke)

I personally found it easier to
feed two TE down the round than the oval.

I have done quite a bit of that in the past (sheds etc) and it does
seem 'easier'. I've also done quite a bit of single in steel as well
and that's everso nice .. ;-)

Do you need to go down and up on each point? Could you chase
horizontally to link some of the sockets and reduce the amount of cable
required and also the joy of getting two pieces of cable down one piece
of conduit.

Well I think it's 6 of 1 and 1/2 doz of the other Paul.

The drops are about half the distance of that between the sockets but
there's all sorts of other crap inbetween (joggles in the wall,
windows, data points etc etc). Plus all the existing feeds are coming
in from 'above' and will end up above their new ceiling ..?

All the best ..

T i m

On Fri, 20 Jan 2006 10:38:55 +0000, John Rumm
wrote:

T i m wrote:

A thought that came out of the grommet end was the use of round
plastic trunking?

The gromit is just there to protect the wires from the sharp edge of the
box. Thermal expansion etc can result in the box slowly cutting through
the insulation otherwise.

Ah, didn't think of the 'thermal expansion' bit John. When I have seen
grommets in the past if you actually pull the cable down the trunking
and out of the box they normally end up threadded on the cable rather
than in the fitting! ;-(

I believe that interfaces directly with the boxes but not sure how it
would handle 2 x 2.55mm T&E rather than singles?

If you are using conduit in wall chases (by no means a requirement - you
can bury directly if desired),

(ok, thanks for that)

it is not a requirement to join it to the
back box. Abutting it ought to be enough. The threadded conduit fixings
to which you refer are more commonly used with exposed conduit when
terminating to surface mounted (often metal clad) accessories.

Ok, understood. I just like the 'mechanical' preciceness of it all
...poke wire in open end of trunking and watch it pop out into box (not
snag everywhere!) ;-)

All the best ..

T i m

On Fri, 20 Jan 2006 01:22:40 GMT,it is alleged that T i m
spake thusly in uk.d-i-y:

[snip]


Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

Personally, I don't twist, but sleeve together.

Ok .. understood. With the 'double sleeving' solution wouldn't there
be more chance of some exposed earth core near the end of the outer
sheath whereas individually sleeving would allow the sleeving down
between the L / N cores and into the outer sheath?

I should probably have qualified: I double sleeve when the cables are
close enough for this not to happen :-)

But yes, it would be a worry if the 2 weren't side by side, if in
doubt, I sleeve everything individually.


Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

I was always taught not to twist, so I don't. I do however twist the
ENDS of the earth wires simply because it feels more solid, (1.5mm
earths on ring circuits usually if using T&E)

Understood

Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

Flexible conduit cable is fine,

As in 'singles' ?

Yes, but also see Owain's sensible point, one that I'd missed:
flexibles may not grip well in combination with solid core, offcuts of
the normal 2.5 T&E earth cable should be fine.

the right gauge of *flex* may not be
correct though, due to voltage rating. In practice it's not going to
matter - especially on an earth - but it could fail an inspection.

Are you suggesting it *should* be flex Chip (ie *not* solid) ?

No, merely that if you do use flex, it should be a compliant type
(flexible conduit single, not stripped out flexible cord).

--
You cannot shake hands with a clenched fist.
- Indira Gandhi

"T i m" wrote in message
...
Hi All,

I had a quick look at the wall chaser, the 32mm oval conduit, the roll
of ,5m T&E and the metal boxes that I'm supposed to be playing with to
halp my mate over the weekend and have some questions.

First some observations:

The oval is due to carry some 2.5mm down from above the false ceiling
line, to double sockets avove the worktop and back up again (in
several places) to become the 'ring'.

The wall chaser has a maximum slot width of 28mm.

The conduit he has is 32mm wide (but can be swapped out).

Looking at the section of the trunking and the 'knock outs' in metal
box it's sorta square peg / round hole(s) thing?

Q's

So, should we use 25mm wide trunking (plastered in the wall) for two
runs of 2.5mm T&E and (if enough room etc) and which of the 4 holes in
the top of the box would *you* bring the cables into (for a std double
socket) and why please?

Do 'people' use the grommets? (I asked him to get a box of them and
would use them myself anyway).


Grommets are not a requirement. What is a requirement is that the cable is
protected from any sharp edges. I suppose you could start deburring the back
boxes etc but it is faster to fit a grommet.

Do you twist the earths together (or not) and sleeve as one or sleeve
individually?

Individually. Earth sleeving is so cheap


Do we still *not* twist the conductors where they enter the screw
terminals in the back of the socket?

Some do some don't.


Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

It does not matter if you do not earth the metal back box with a seperate
flylead as long as one of the lugs you connect the front plate to is fixed.
I have not seen new back boxes with 2 adjustable lugs for a long time now.

Adam

T i m wrote:

Ok, understood. I just like the 'mechanical' preciceness of it all
..poke wire in open end of trunking and watch it pop out into box (not
snag everywhere!) ;-)

Its nice in theory ;-) Feeding T&E through conduit however it a PITA
IME. Not too bad on short runs like drops to light switches it has to be
said.

How much use it is depends on how accesable the top of the conduit will
be in future (i.e. if there is any possibility of getting at it to
replace a wire should there be a requirement).


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Fri, 20 Jan 2006 17:27:17 GMT, "ARWadsworth"
wrote:


Does it matter if you use flex or solid between socket and metal box
(as long as it's the right colour and gauge etc)?

It does not matter if you do not earth the metal back box with a seperate
flylead as long as one of the lugs you connect the front plate to is fixed.

Ah, ok ..

I have not seen new back boxes with 2 adjustable lugs for a long time now.

Nor me .. ;-)

Thanks for the other comments Adam ..

All the best ..

T i m

In message , T i m
writes
On Fri, 20 Jan 2006 10:53:48 +0000, chris French
wrote:


Understood Chris .. and by 'terminate' I don't really mean a real
engineering solution, just one where half the oval isn't looking at
some galv steel rather than hole?

That's east enough to arrange, usually I find it lines up ok, if not
little bit of packing does the job.

Ok, understood. Do they make boxes with OVAL knockouts!

Not that I know of.


It's also my thought that it might be easier to 'fill' a slightly
deeper chased slot filled with a round trunking *because* you have
more depth for any filler to attach to (someting wider and flatter
(and still plastic) being worse)?

no, sorry I think that's a load of rubbish :-)

Oh? From a mechanical point of view I can't see how you could get as
good a bond to the sides of a 10mm deep slot as you could to the sides
of a 20mm deep cut shrug?

Ok theoretically there might be better bond, practically I don't think
it makes any difference.


I'm also doing 15 of such drops so I want it to be as predictable as
possible?

All the more reason for not over engineering it then....?

Good point .. and you are probably right .. sigh ... cept I see it
as 'easier engineering' ...?

1) I find the idea of cutting a 20 x 20 slot (and breaking out the
centre rib) being easier than a 40 x 10 slot and breaking out the
middle to leave it flat and consistant, pleasing.

2) Knowing that my round tubing is mecanically attached to the box and
centered in the hole (and with no rubber grommets falling out) gives
me pleasure.

3) Being able to freely slide the cable through the trunking freely
(as a pair, often easy or one beside the other, often less easy),
rewarding.

4) Knowing that I can access any of it to replace / upgrade / move
later on, satisfying.

But no, I'll do what everyone else does because it's quicker, cheaper
or 'will do', in spite of that fact that none of those give me
satisfaction ..? big sigh

Then do it the way that gives you satisfaction, - isn't that one of the
benefits of diying
?
--
Chris French

Sorry - missed the start of this thread, so to the OP on the presumed
question of round_holes-oval_conduit:

These do *exist*:

http://www.act-comm.com/prodpages/trunking/conduit.htm

(5th pic down from left top)

But they are not that common - ie I've never seen them for sale in any
normal merchant.

Tim

On Fri, 20 Jan 2006 21:52:02 +0000, chris French
wrote:


But no, I'll do what everyone else does because it's quicker, cheaper
or 'will do', in spite of that fact that none of those give me
satisfaction ..? big sigh

Then do it the way that gives you satisfaction, - isn't that one of the
benefits of diying

Well sorta ... but them my missus will say 'what would you rather be
doing .. out riding on our motorbikes or making a fantastic job of
that when no one will now .. " ?

Whilst I agree on paper I can't help doing stuff to the best of my
ability .. ;-(

All the best ..

T i m

On Fri, 20 Jan 2006 21:53:05 +0000, Tim S wrote:

Sorry - missed the start of this thread, so to the OP on the presumed
question of round_holes-oval_conduit:

These do *exist*:

http://www.act-comm.com/prodpages/trunking/conduit.htm

(5th pic down from left top)

But they are not that common - ie I've never seen them for sale in any
normal merchant.

Damn .. there goes my millions ... ;-)

Thanks for that though ..

T i m

On Fri, 20 Jan 2006 19:54:47 +0000, John Rumm
wrote:

T i m wrote:

Ok, understood. I just like the 'mechanical' preciceness of it all
..poke wire in open end of trunking and watch it pop out into box (not
snag everywhere!) ;-)

Its nice in theory ;-) Feeding T&E through conduit however it a PITA
IME. Not too bad on short runs like drops to light switches it has to be
said.

I think I've found it easier to pull than to push? And getting it
straight first helps of course ;-)

How much use it is depends on how accesable the top of the conduit will
be in future (i.e. if there is any possibility of getting at it to
replace a wire should there be a requirement).

Well he's going to have a suspended ceiling (plasterboard on a metal
frame) with access hatches in at regular intervals. So access won;t be
*easy* but not impossible and extra hole could be cut / made good if
*very* important?

Al the best ..

T i m