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Topic Title: Trivial but annoying!
Topic Summary: Surface boxes
Created On: 20 November 2012 07:54 AM
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 20 November 2012 07:54 AM
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SherlockOhms

Posts: 313
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Chaps,

Could anyone tell me why surface boxes are made of such a brittle material? Bone china is probably more resiliant!!

How many do you throw away after they crack whilst removing cutouts?

S.
 20 November 2012 08:58 AM
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hifly

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i use a rotory file in my drill makes a nice smooth hole and no cracking. can't same the same when i screw them to the wall.

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 20 November 2012 09:01 AM
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vesuvius

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I think your referring to bakelite back boxes, commonly used where the likes of twin and earth cables would be entering the box through the notorious knockouts.

You can of course get more rigid plastic boxes probably like a thermoplastic. They have the 20mm knockouts for surface conduit instllations etc.

the only reason i can think of would be a costing issue, and its probably not a massive difference depending on where you buy your gear from. they are a pain in the back side though
 20 November 2012 09:09 AM
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Legh

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Nibble with pair of side cutters.and then a round file to clean up the rough edges.
Mind you there are different types of plastic. conduit = soft and T&E = hard.

Legh

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 20 November 2012 10:42 AM
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AJJewsbury

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I used to cut the sides of the "knockout" with a junior hacksaw blade (the inner is bevelled, so the blade at 45 degrees just cuts the outer wall, not the base), snap off and then tidy up with a small file. It's time consuming, but you can get a nice snug fit around the cables.
- Andy.
 20 November 2012 08:14 PM
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kaichung

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Have you tried the rigid white UPVC boxes from MK or Marshall-Tufflex?
They are well made, stronger, and they work out cheaper over the long run, when wastage is accounted for (say one in three boxes).
 20 November 2012 08:33 PM
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mikejumper

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Originally posted by: SherlockOhms
Could anyone tell me why surface boxes are made of such a brittle material? Bone china is probably more resiliant!!

Probably to do with flammability and ease of moulding.

I agree though, they are brittle.

Judging that final turn of the screw to secure a surface box to the wall is alway a tense moment.
 20 November 2012 08:41 PM
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stateit

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Originally posted by: kaichung

Have you tried the rigid white UPVC boxes from MK or Marshall-Tufflex?

They are well made, stronger, and they work out cheaper over the long run, when wastage is accounted for (say one in three boxes).


That's a high rate of attrition there kaichung!

I like using the uPVC ones as well, but they don't visually match up with the urea formaldehyde accessories.

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 20 November 2012 10:53 PM
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Martynduerden

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Originally posted by: AJJewsbury

I used to cut the sides of the "knockout" with a junior hacksaw blade (the inner is bevelled, so the blade at 45 degrees just cuts the outer wall, not the base), snap off and then tidy up with a small file. It's time consuming, but you can get a nice snug fit around the cables.

- Andy.


Ha a fellow box cutter,

I haven't broken an MK box to date - quickly touches so wood

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 21 November 2012 10:07 AM
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OMS

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Originally posted by: Martynduerden

Originally posted by: AJJewsbury



I used to cut the sides of the "knockout" with a junior hacksaw blade (the inner is bevelled, so the blade at 45 degrees just cuts the outer wall, not the base), snap off and then tidy up with a small file. It's time consuming, but you can get a nice snug fit around the cables.

- Andy.


Ha a fellow box cutter,

I haven't broken an MK box to date - quickly touches so wood


That's how I was taught to do it as an apprentice - although snapping them out with a 6" pliers and slapping the box on the wall with 2 x 1" No 8 woodscrews becomes the norm once you ventured out on site.

With T&E cable you used to saw out, clean up with a square file and round the corners with a rat tail file to match the T&E profile - the opening was always ever so slightly smaller than the cable to create a slight interference fit - not quite IP65, but close -

Not overtightning the fixing screws is the key - back in the days we used screwdrivers for slotted screws, you could "feel" the point when enough was enough - bashing them in with posidrives and a power driver doesn't give you that feedback so more boxes get crunched

Regards

OMS

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 21 November 2012 11:52 AM
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Martynduerden

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Originally posted by: OMS

Originally posted by: Martynduerden

Originally posted by: AJJewsbury

I used to cut the sides of the "knockout" with a junior hacksaw blade (the inner is bevelled, so the blade at 45 degrees just cuts the outer wall, not the base), snap off and then tidy up with a small file. It's time consuming, but you can get a nice snug fit around the cables.

- Andy.


Ha a fellow box cutter,

I haven't broken an MK box to date - quickly touches so wood


That's how I was taught to do it as an apprentice - although snapping them out with a 6" pliers and slapping the box on the wall with 2 x 1" No 8 woodscrews becomes the norm once you ventured out on site.

With T&E cable you used to saw out, clean up with a square file and round the corners with a rat tail file to match the T&E profile - the opening was always ever so slightly smaller than the cable to create a slight interference fit - not quite IP65, but close -

Not overtightning the fixing screws is the key - back in the days we used screwdrivers for slotted screws, you could "feel" the point when enough was enough - bashing them in with posidrives and a power driver doesn't give you that feedback so more boxes get crunched

Regards

OMS
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Want a job ?

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Martyn.

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 21 November 2012 12:11 PM
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OMS

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LoL - as a summary:

Must turn up
Must work ... All day
Must not bugger off to do other jobs
Must be able and willing to do high quality
MUST NOT TWIST CABLES - that's my OCD
Must be able to do more than electrical work
Mush have a modicum of common seance
Must not winge when arriving home having missed neighbours


All of the above - you can get me for about £2K for a five day week

Must not smoke in the house


Priceless - I need at least one B&H an hour - I won't smoke in the house but my smoking rate is £80/hr pro rata - I need at least one 5 minute B&H session every hour

When do you want me to start -

Regards

OMS

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 21 November 2012 01:34 PM
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SherlockOhms

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Well yes it's not hard to make a nice neat job of it but if ever a product needed a make-over it's this.

What's wrong with some nice, easy to remove, T+E shaped knock-outs and all in a material that isn't going to require you buying three times as many as you........ah, now I get it.

S.
 21 November 2012 02:05 PM
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Martynduerden

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Originally posted by: OMS

LoL - as a summary:

Must turn up

Must work ... All day

Must not bugger off to do other jobs

Must be able and willing to do high quality

MUST NOT TWIST CABLES - that's my OCD

Must be able to do more than electrical work

Mush have a modicum of common seance

Must not winge when arriving home having missed neighbours


All of the above - you can get me for about £2K for a five day week

Must not smoke in the house


Priceless - I need at least one B&H an hour - I won't smoke in the house but my smoking rate is £80/hr pro rata - I need at least one 5 minute B&H session every hour

When do you want me to start -

Regards

OMS


Could about 2k be £800?

I reckon I could spare you 2 hrs a day for fags

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 21 November 2012 02:19 PM
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OMS

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Well I could do the first 7 criteria for £800/wk

If you want some who won't moan about missing Neighbours then that's another £1200 -

I can smoke an awful lot of fags in 2 hours Martyn - 5 mins/hour will do me - think about it like a display screen equipment assessment - the advice is take a break every hour, so smoking is my way of complying - I thinks that points 6 & 7 covered -

Seriously - there must be some bugger on here looking for a week or so's work ?

Regards

OMS

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 21 November 2012 02:24 PM
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Martynduerden

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Originally posted by: OMS

Well I could do the first 7 criteria for £800/wk



If you want some who won't moan about missing Neighbours then that's another £1200 -



I can smoke an awful lot of fags in 2 hours Martyn - 5 mins/hour will do me - think about it like a display screen equipment assessment - the advice is take a break every hour, so smoking is my way of complying - I thinks that points 6 & 7 covered -



Seriously - there must be some bugger on here looking for a week or so's work ?



Regards



OMS



2 hours was 5 minutes per hour maybe it was too cryptic

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Martyn.

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 21 November 2012 02:43 PM
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OMS

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LoL - I see, it's 24/7 then Martyn - that's almost as bad as my day job.

Regards

OMS

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 21 November 2012 03:09 PM
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bartonp

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Sharp tap with pointly screwdriver, rake L&R to clean up sharp bits. 10 seconds, never broken one.
Must be a knack.

Phil.
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