How to get cable past chicane in capping

[bernardgreen]

30 minute job became a night mare.

Changing a single gang switch to a two gang for a second lamp in the room. Triple and earth runs vertically down from loft under capping for a two way circuit. Plenty of room for the exiting triple and earth and the new twin and earth in the capping immediately above the switch. No back box, switch is woodscrewed to a timber box in the stud wall.

Pulled triple and earth up into loft pulling in a draw cord. Now cannot get any cable back down behind the capping. It looks like pieces of hard plaster are partially clogging the capping requiring the cables to go through a chicane in the capping about 6 inches down from the ceiling. The rafters are about 10 inches above the ceiling so a long drill down is not possible.

Triple and earthare now terminated in JB to allow other two way switch to control lamp.

Any ideas on getting the capping clear. ?

 

[sparkwright]

Not sure about the bit where you say it's a stud wall, and with capping.

I suppose trying to pull a narrow drawire through the capping should empty out the capping, depending how big these bits of rubble are.

Perhaps a straightened out coat hanger may help you clear the capping.

I assume you want a 2 way switch and a one way switch at the switch position. If both lights on the same circuit you should be able to achieve this with just two twin and earth cables at the switch, and a bit of joint in the loft.

 

[bernardgreen]

Not sure about the bit where you say it's a stud wall, and with capping.

These houses were built down to a low price in the 1960s and the construction appears to be stud with plaster board. Sometime later it seems they were re-furbished and extra cables were laid on or in the plaster board and capped before a thick coat of new plaster was applied to the wall as part of a sound proofing exercise.

I suppose trying to pull a narrow drawire through the capping should empty out the capping, depending how big these bits of rubble are. Perhaps a straightened out coat hanger may help you clear the capping.

First method used but the obstruction appears rock hard. I am thinking about using a flexible saw wire if I can find a source.

I assume you want a 2 way switch and a one way switch at the switch position. If both lights on the same circuit you should be able to achieve this with just two twin and earth cables at the switch, and a bit of joint in the loft.

Good thought, they can be on the same ciruit. JB would be easily accessible

 

[OwainDIYer]

use wireless switches?

 

[bernardgreen]

use wireless switches?

It might come to that for the new lamp but the problem of getting the triple and earth back in place for the existing circuit remains. I will be attacking it again tomorrow

 

[JohnW2]

Pulled triple and earth up into loft pulling in a draw cord. Now cannot get any cable back down behind the capping. It looks like pieces of hard plaster are partially clogging the capping requiring the cables to go through a chicane in the capping about 6 inches down from the ceiling. The rafters are about 10 inches above the ceiling so a long drill down is not possible.

If the blockage is only 6" down, I suppose you might just about be able to manage with a right-angled drill and an ~10" drill bit. Failing that, a flexible 'waste pipe cleaner' (basically a 10m long steel coil spring) is what I would normally try in that situation. Otherwise, as you've suggested, anything fairly solid yet flexible. Of course, if you were planning on redecorating in the near future, you could excavate the wall in the vicinity of the blockage and 'sort it out' that way. Good luck - that sort of problem is very frustrating, but only too common!

Kind Regards, John.

 

[stillp]

If the blockage is only 6" down, couldn't you just poke a 12" hacksaw blade down and saw away the blockage? (Tip - tie a length of string through the hole in the end, so when you catch your fingers and drop the blade down the capping, you'll have something to pull it out with.)

 

[sparkwright]

So if it was originally a stud wall you may be able to get a new cable through the studwork in the hollow section.

 

[securespark]

Whichever way you have inserted the wire to clear the obstruction, try going the other way.

 

[bernardgreen]

Whichever way you have inserted the wire to clear the obstruction, try going the other way.

A prolonged session with stiff wire ( ex coat hangers ) formed into zig zags created a pile of plaster dust on the floor below the switch. Pushing new twin and earth up from below then was successful but even then crumbs of plaster were pushed up out of the capping. The twin and earth was then used to pull in replacement triple and earth ( two way switching )

The idea of a second lamp as been abandoned

 

[securespark]

The idea of a second lamp as been abandoned

Booo! You part-timer!

 

[JohnW2]

The idea of a second lamp as been abandoned

If you utilised a wiring arrangement which allowed you to have one conductor common to both light switches (not difficult), you could pull a 5-core flex through and do it that way.

Kind Regards, John.

 

[Alarm]

Tut tut Bernard. Poor show

 

[bernardgreen]

It wasn't me that abandoned the idea. It was the tenant in the house who halfway through realised the landlord might not be happy to find an extra lamp in the house.

I had thought of five core ( which I have a reel of ) for when (if) the route was cleared but Murphy's Law applied and it was two strappers and the switched live to the lamp in the triple and earth. The permanent live was at the other switch. ( I haven't got any 6 core, 12 is the next one )