How To Strip Doubled Over Twin And Earth.

[Eric Cartman]

Hi All

Im replacing my ring main and also adding a new radial lamp circuit.

Now as I understand it in an ideal world the best way to run the cable is from socket to socket in one continuous length. So you double over the cable, insert this loop of cable through the grommetted back-box, from the loop strip the outer sheathing and inner insulation, slip some earth sleeve on the earth and you are done.

What is the easiest way to strip the sheathing and insulation? I have basic wire strippers, side cutters, stanley knife etc... It just seems like Im either going to loose some fingers or damage the wire when it's doubled over as you can't use the strippers in the usual way?

Cheers

[rrh]

I sometimes doe this with live and neutral, more as a conceit than because it's necessary (as mrcheerful says the earth needs a sleeve so you will need to cut that). I simply shave away the outer sheath and then the insulation carefully with a stanley knife. Obviously you must get the length of cable exactly right and bare the conductors in exactly the right place.

[Christian McArdle]

You can get the sleeving to go over both earth conductors if you squash the bend over end with pliers.

Christian.

[BigWallop]

Excuse me people, but why not cut the cable and fit both ends to the socket properly. Doubling the cable over and the trying to push it through the grommet in the back box alone is going to be a hell of a job. Bring the cable to where the socket is to be positioned. Cut the cable enough to take into the back and connect to the socket. Wrap both earth connecting cores together over their full length and slip the sleeving over them. Connect earth to back box along with the earth fly lead that reaches to the socket plate.

It isn't difficult really. But the mess you lot are making of it, you'll be there till Christmas doing the one socket. :-)) I do the whole fitting with a pair of pliers and a screw driver.

[Rob Morley]

Why - it's still just two 2 1/2 T&E?

Which means that if any of the screws come loose it could break the ring and you'd never realise it. If you don't cut the cable you can't easily break the ring.

It's really not difficult to do it without cutting the cable - someone already described how to split the insulation lengthwise with a Stanley knife.

[Tim S]

Or "cable minimum bend radius" is another term

Applies to fibre optics too. Back in the 80's when fibre optics were a new thing to many sites, the uni I was at had a load of FO installed. For some interesting reason, the cable pulling contractors tied a tight knot in the end of each cable (to stop the fibres falling out?).

Bloke in charge of the job had a fit. IIRC the contractors had to redo some runs as there wasn't enough left after chopping off the damaged portion.

Timbo

[bob]

Bends in FTE cable should not exceed 3x dia, (less than 10mm2) if you "squash" it flat then it does not comply with BS7671, you may as well just cut it and fit appropriate terminals Bob

[BigWallop]

Exactly. Get a cut, even a small one, in or on the conductor insulation and your cable is useless because it will leak.

LOL!!! That sounds just like a cut in a hose as well, don't it? :-))

[BigWallop]

By grabbing the end of it with pliers after you cut it clean through, and then pull it. This leaves a little open flap after the outer sheaf is cut to length, and you use that little flap of PVC to hold the tape once the green/yellow sleeving is fitted. The tape stops the sleeving from slipping around when you're moving the earth core about to connect it to the back box.

The way things are going just now. It may become compulsory to use proper heat shrink sleeving over the outer PVC coating and the ends of the inner PVC coverings once the green/yellow sleeve is slid on. But hopefully that will be years away yet.

[Dave Plowman (News)]

Properly tightened screws don't just come loose. And if you're drawing high current off a socket where the screws are loose the cable will soon become toast anyway - regardless of being continuous.

[Dave Plowman (News)]

Yup - use the knife to start it then pull the earth with pliers.

[Rob Morley]

You stab it where you're going to strip the conductors anyway.

[mrcheerful]

but that was not what the op asked , was it?

mrcheerful

[Ian Middleton]

I watched a friend try to wire up his recently rewired rooms with just ring main loops of cable hanging out the boxes (sparky buggered off leaving job unfinished) he spent ages carefully stripping, folding, bending, more folding, more bending finally screwing and then couldn't place socket on box as too much cable to squeeze in !!! So he had to cut out cable, restrip, twist together, screw into socket, place socket on wall, job done, much much quicker. This was 16 years ago and his house hasn't burnt down.