How to get a wire behind the ceiling?

[Timothy Murphy]

I'm trying to move a pull-down switch from one side of a bathroom door to the other. (At some time the door was hung the other way, I guess.)

The ceiling is wooden, and I have made a 2cm hole at the new site, and verified (with a bent metal hanger) that there is no obstruction between the two holes, which are about 1 metre apart.

But how can I get a wire from one hole to the other? To explain what I mean, if I tied string to a mouse's tail, and pushed it up through one hole, and put cheese up the other hole, the string might go from one hole to the other. Unfortunately we have no mice in residence.

Any suggestions gratefully received.

[Bob Smith]

Can you not go into the loft? To pull the wires I mean, not to find a mouse.

Bob

[The3rd Earl Of Derby]

If there is no obtrusion whatsoever ie battens/insulation? in the ceiling path then tie a 2" inch nail to a piece of string feed it into the hole, get a STRONG magnet and draw the nail/string to tother hole with magnet along the ceiling. You can then draw the cable across with the string tied to it.;-)

-- Sir Benjamin Middlethwaite

[Bob Smith]

How about training a rat?

[Andrew Gabriel]

Can you not get the hanger wire to go from one to the other by bending it appropriately? Another option would be something a bit more flexible, like a length of T&E, or a single conductor from it -- push it in so the end is running along the top of the ceiling and eventually drops through the other hole.

I've done this sort of thing lots of times, but it can take quite a bit of patience before it works.

With a plasterboard ceiling, you can drill intermediate holes so you don't have to hop across in one go, which are easy to fill invisibly afterwards. With a wooden ceiling (unless it's painted) that's probably not an option.

[Lobster]

Assuming you can't tackle the problem from above (loft space? lifting floorboards of floor above?)...

A bit hard to advise without seeing the circumstances, but I'd say somehow you want to be looking put a loop of string up one hole, then hooking it using a stiff wire (eg coathanger) or similar introduced up the other hole; once you've got a length of string running from one hole to the other the rest is easy ansd self-evident.

Is there plenty of head room above the ceiling, eg can you push a 1m length of coathanger wire up vertically in one hole, and let it fall towards the second? Or is there room to slip the coathanger wire in almost parallel to the ceiling, and slide it in fully?

I have one of these sets which would probably be ideal in this scenario, but might be more than you'd want to spend for a one-off job:

or

David

PS I did actually once use a borrowed pet rat to run some cables under a floor - worked like a charm!!

[Rob Morley]

Bend the end of the coathanger into a hook, tape the end of the cable into a loop and go fishing :-) Or it might be easier to use two bent coathangers, each hooked.

[Andrew Gabriel]

A couple of other things I use and should have mentioned: Expanding tape measure -- works well if you can get it and a finger through the hole, so your finger can bend it to run flat across the ceiling towards the other hole. Flat sprung metal drain clearers -- similar to the expanding tape measure but stiffer.

Also, with either of these, if you can't get the end directed to the other hole, you can just keep stuffing more and more into the ceiling, and eventaully one of the loops will become visible at the other hole, and you can capture it.

BTW, when blindly poking pieces of metal into the ceiling near wiring, I would suggest making sure the supply is switched off, incase it finds something like a junction box with lid missing, or some other horror of which you are not aware.

[Brian Reay]

Two retractanble tape measures.

In the first one form a loop and push through one hole- enough so it expands into a big loop in the void.

Tape a bit of string to the end of the other and pushthrough the other hole toward the loop. Push until you are sure to have gone past the loop.

Pull loop "in" so you can see second tape and string through whole and catch string with a wire hook.

Remove tapes, leaving string in place and use string to pull through wire.

[daddyfreddy]

Have you got any of those bendy wires to hold up net curtains? I'd use one of them to get to the other hole.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Timothy Murphy saying something like:

Pity it's a wooden ceiling; if it was plasterboard, you could just make a bigger hole and fill it later.

All you can do is put a relatively stiff fishing wire through one hole wiggle it about in the vicinity of the other hole and hope to grab it with a pair of taper-nose pliers.

[Timothy Murphy]

Thanks for the many suggestions.

Most involved using something like a curtain wire or drain cleaner to go from one hole to the other. I have both of these, and will try that first. I'll also try a metal tape measure, though I don't think I have enough room to put my finger through to press it down.

I can't access the ceiling from the room above, at least not easily. It would be in the middle of a bedroom floor with a carpet on it.

I like the idea of a magnet, but I'm not sure where I could get a sufficiently strong one. In my youth I would have constructed an electro-magnet, but I no longer have the components for this. But if all else fails I'll go back to this.

Thanks again - I'll let you know how it goes.

[Cicero]

====================== Look here:

[Bill]

In message , Cicero writes

have one similar and it saves a lot of time.

[Sadly]

If there isn't too much dross in the space (especially no insulation!!) you could try holding the hose of a vacuum cleaner to one hole while you poke string through the other - if it gets close enough it should get sucked across.

May not work, but could be worth a try!

[Dave Plowman (News)]

Tie/tape some strong string to the front of the coat hanger and pull the string out of the new hole.

[Set Square]

He'll need a big hole in the ceiling, to get that through.

Actually, I wonder whether it would work through the thickness of the wooden ceiling (in a similar way to that in which magnetic window cleaners are supposed to work)? If so, he could poke a metal object with string attached through the hole, and drag it above the ceiling to the other hole by moving the magnet below the ceiling.

[Cicero]

====================== I wasn't suggesting that the magnet should go inside the ceiling. I was simply following up the suggestion from an earlier poster about using a magnet. In fact this method (using a magnet to drag a nail or needle from under the boarding) is a well-established method which works very well on hardboard ceilings (in caravans) and on plasterboard ceilings. It might not work so well on a wooden ceiling depending on the thickness of the wood. However the magnet shown (Screwfix) is a very powerful magnet as its intended purpose is to hold substantial bits of steel for welding. I think there's every chance that it will work as suggested. However, I think that one of the other methods suggested would be just as likely to succeed because the distance to be bridged is only one metre which is hardly any distance at all.

Cic.

[The3rd Earl Of Derby]

Wooden ceiling hmmm! T&G the 3" stuff, springs to mind?

-- Sir Benjamin Middlethwaite

[Timothy Murphy]

but I didn't understand how it is meant to work.