Mounting telephone extension box on drywall

[tristan]

Hi,

I've wired up a telephone extension. The wire is routed through some drywall and pops out the other side in the room where the box is going to attach.

I've got a plastic surface mount box (combined with a telephone/ADSL dual socket front plate).

To begin with, and until I get more confidence with cutting holes in the wall, I'm going to surface mount this. Given it is drywall I'm not sure the box I have could be recessed anyway - wouldn't it just fall into the gap? What would keep it in place?

The box has various dimples to indicate drilling points. I want to drill them without shattering the plastic. Is there any particular advice on doing this?

There are 11 of these points around the rear which is nice. I presume two should be enough for a firm fitting...

Thanks in advance,

Tris.

[Tim Southerwood]

You get a special drywall back box - these have lugs to engage and grip the back of the plasterboard whilst a front lip prevents it falling through.

It's not hard to cut PB - mark around the drywall back box, making sure you are clear of any wall struts. You can get away with a stanley knife, cutting progressively - or use a hand held hole saw and a drill on 2 corners.

I just punch them out with a small screwdriver and a light tap with the palm of my hand.

Generally. If you are not confident of your fixings, use 4, but 2 are usually OK for a telephone plug.

[Roger Mills]

I'm not quite sure what type of box you've got. If you're flush mounting on plasterboard which has a gap behind it, you need one of these:

little yellow bits are spring-loaded and slide *behind* the board so that when you fit your socket and do the screws up, it is all gripped tight. It's quite easy to cut a neat box-sized hole in plasterboard using a tenon saw - or even a jigsaw with a short blade.

If you're surface mounting, you need a different sort of box - something like

would have to fix that to the board with a couple of screws, using suitable plugs for plasterboard. If you want it to be *really* firm, use these

[tristan]

Thanks. After some consideration I think I will go this way -- all the other sockets in the house are flush, and I want to avoid this sticking out any further than the skirting board (which it will do if surface mounted). Usual furniture considerations...

I've held the back box up to the light now and can see that they are "weaker", as are various points arounds the side. So this should work nicely. Although this seems redundant now!

I'll pop down to B&Q in a bit to grab a 85mm dry-line box. From memory though, when I was last there they only had these in metal. I presume I can mix a plastic front plate with a metal back, given that this has been used for the electrical sockets!

[The Natural Philosopher]

Actually having tried everything, my favorite is a slender serrated kitchen knife.

The phone front plate should mate up to a drywall box perfectly..or simply get a normal phone front plate. They are not expensive.

[Tim Southerwood]

That's a very nice idea.

[Lurch]

On 20 Apr 2007 03:54:19 -0700, " [e-mail]" mused:

A metal box isn't a dry lining box. It doesn't have the lugs to hold it in the plasterboard. B&Q will do dry line boxes though, you just didn't know what they were last time you saw them!

[Dave Plowman (News)]

It's a bit more complicated if you want to use a metal box as they are normally set into solid plaster/brick, etc. But it can be done. Make up some wood battens slightly longer than the sides of the hole and glue to the back of the plasterboard lined up with the edge. You next need to drill some holes in the sides of the box as there won't be any in the right places. Then fix through these holes with screws into the wood battens. When you fix the front plate to this it will clamp together and be much stronger than a dry lining box - and neater looking too. If you have to decorate anyway you can use screws to hold the battens to the plasterboard - but best use brass screws for this job as steel will rust after being filled over.

[Bob Eager]

They aren't metal, usually, but plastic. The metal ones are for embedding in brick and plaster (IME). The plastic ones are usually white, with red lugs on the sides. Typically you cut the drywall with a Stanley knife (make it a snug fit). Slide the lugs sideways so that they are inside the walls of the box. Insert the box up to the 'lip'. Push the lugs outwards (about a centimetre AFAIR). Then pull them forward to sandwich the drywall between the lip on the front of the box, and the lug itself. Attack the front plate, using screws into the holes in the lugs, and that pulls the lugs against the back of the drywall.

[tristan]

I popped down at lunchtime and got one. To be precise, I got 5 --- they were completely sold out of the single boxes for some reason, and I only got the five-pack by hunting behind the shelves!

It isn't a fancy one with spring loaded lugs but looks like it will do the trick.

I had to pick up some screws as well -- bizarrely, the fancy ADSL/ telephone filter faceplate I bought came with screws which fit its own backplate only...

[Dave Liquorice]

You and me both...

I find a Stanley Wood Knife Saw Blade quite good:

or with finer teeth:

in appropiate handle of course.

[Dave Liquorice]

But NOT the front of the box, the rear.

And risk losing your fingers. What did I end up with? 9 stitches around end of 2nd finger from base of nail around the pad side to almost base of nail the other side (still haven't got proper feeling in the end and this was 7 years ago...), another 4 stitches across the inside of the top joint of my third finger.

[Roger Mills]

Are you sure that you've got the right ADSL component? Filtered faceplates are designed to fit onto a BT linebox in place of the standard faceplate,

*not* directly into an empty back-box.

[tristan]

I know what you mean. I have one of these though:

dual socket on the far right)

I've decided to go for this solution as although I could fit the NTE5 one on the master (thus filtering all the telephone sockets...), I wanted a point in the study which would serve both ADSL and a phone.

Anyway, I've tested the above splitter tonight and it is working.

I've also made the hole in the plasterboard, by way of stanley knife and metal ruler (I'm going to have to use better tools next time though, I think it was more luck than judgement that everything worked out). Backbox fits great. I haven't done the final wiring yet though.

I do need to adjust the backbox slightly... it's not straight by just a few degrees (if that). What's the best way of gently rotating it? Just filing the plasterboard at the sides? (I know that the ideal solution would have been to get it straight first time).

Thanks,

Tris.

[Dave Liquorice]

Both types are available:

course there is confusion caused by calling these things "ADSL filters" as the ADSL *isn't* filtered it is the analogue phone connections that are filtered.

[Roger Mills]

Fair enough - Solwise seem to have changed their terminology! In the old days they would have called the ADSL-NTEFACE a faceplate, and your device would have been a slave socket with filtered and unfiltered outlets, or somesuch.

Fine - but you'll also need filters in any other sockets where analog equipment (phones, faxes, etc.) is plugged in. Using a filtered faceplate (old definition!) in the master socket would have been a better solution technically - but you would then have needed digital extension wiring to the study in addition to the analog wiring.

I wouldn't have - and didn't - recommend a Stanley knife for cutting a hole in plasterboard, although it's fine for scoring prior to dividing a large sheet into two. A small sharp saw is required for what you were doing.

If the sides of the hole are not horizontal and vertical, you will have to make the hole slightly bigger to square it up. Try to remove as little as possible. You may find that you can rotate the faceplace *slightly* in the box - to get *that* straight even though the box isn't. Slacken the screws a bit, twist the faceplate in the appropriate direction, and re-tighten the screws.

[JohnW]

I agree with your first statements but the end is not completely correct - all the wiring is "analog", it's just that some carries the broadband RF signals as well as the up to 4Khz telephony signal.

With the Solwise ADSL-FFP85D filter the OP fitted, he could still install a master faceplate filter and run the unfiltered side from the new master faceplate to the Solwise filter and the filtered side to any other phone sockets. You can get master faceplate filters that have both filtered and unfiltered IDC connectors on the back e.g.

is no need for any filtered telephone wiring (your "analog wiring") to go to the Solwise. You simply wire through the unfiltered, combined broadband + telephony signal, wire (It's not "digital wiring", as you state) and the Solwise will split off the telephony part of the signal for local phones.

[John Rumm]

A, & B

[Lobster]

I prefer a purpose-designed pb saw - mine's something like this:

The blade is very stout and stiff so won't bend or snap; has a pointy tip which you can easily wiggle right through the board in order to get the blade through for the first cut; it has very coarse teeth so cuts very quickly; it's tapered from tip to handle so you can make round holes of whatever size by advancing it through the pb like a manual drill; and costs peanuts so is a no-brainer addition to the toolbox IMHO!

David

[The Natural Philosopher]

If you loosen up the hole, you can hold the thing straight when you screw the front plate on - once tightened up it all clamps together.

If you have any visible gashes, take thefront off, repair and sand the plasterwork, and paint - you can paint over the box - and reapply the front plate.