Switch screw problem- earthed?

[motso]

Hi all,

Long time admirer of the site but never had to create a post before!

I've changed a couple of old switches in my hallway to new metal ones- this seems to have been successful (still alive) except for a problem with a two way single switch. I can't for the life of me get one of the fixing screws on the faceplate to go in, I wasn't the one who removed it so am unsure if it was like this on the old one. The lug (the bit it screws into?) seems to move up and down so maybe broken. I have managed to screw in the other one and it somehow looks fine and does not slip but I read somewhere that the screws act as an earth so is it unsafe to leave it as it is?

I earthed the faceplate to the backbox as well as fixing the mains earth to the face plate.

Any advice much appreciated,

Thanks

Tom

 

[JohnW2]

I can't for the life of me get one of the fixing screws on the faceplate to go in, I wasn't the one who removed it so am unsure if it was like this on the old one. The lug (the bit it screws into?) seems to move up and down so maybe broken. I have managed to screw in the other one and it somehow looks fine and does not slip ....

One of the 'lugs' is meant to move up and down - to allow fine tuning of the positioning of the faceplace if the box is not perfectly horizontal/vertical. 'Aiming' the screw into the movable lug can sometimes be difficult - you probably need to try to get that one 'in' before you do the other (fixed lug) one. It's possible that the thread in the lug is damaged - in which case you can get hold of a M3.5 're-threading tool' very easily/cheaply.

... but I read somewhere that the screws act as an earth so is it unsafe to leave it as it is? ... I earthed the faceplate to the back box as well as fixing the mains earth to the face plate.

If faceplate, back box and cable earth are all connected with wires, then the screws are electrically unimportant.

Kind Regards, John

 

[motso]

Hi John,

Many thanks for the speedy reply- kind of what I hoped someone would say!

Agree with your other sensible comments- the threads fine I tested it I can't work out why it won't go in tried for about 45 mins before giving up! Will try again another day.

Is 'lug' the correct terminology?

Thanks

Tom

 

[JohnW2]

Hi John, Many thanks for the speedy reply- kind of what I hoped someone would say! ... Agree with your other sensible comments- the threads fine I tested it I can't work out why it won't go in tried for about 45 mins before giving up! Will try again another day.

If the screw will screw into the lug OK without the faceplate involved, then I think it's probably just an 'aiming/fiddling' issue!

Is 'lug' the correct terminology?

I'm not sure - but that's certainly what I would call it

Kind Regards, John

 

[securespark]

It's what I have been calling it since 1984....

 

[PrenticeBoyofDerry]

As John has mentioned, you will have one rigid lug and one loose that allows for adjustment of the faceplate.
I would take the screw out that currently fixing the rigid lug.
Then without faceplate make sure the moveable lug will take the screw and the lug or/and the screw has not become threaded.
If both okay then I would fix the loose lug first to the plate, so it has taken hold but not completely tight, then screw the rigid lug, as the rigid lug is not going to move around when trying to hole the screw.
Sometimes the lugs and screws become threaded, so screws need replacing and lugs can be rethreaded with a threading tool or the loose lugs can be replaced.
If you have put a earth tail between plate and backbox having the screw not fixed will not effect the earth continuity, as you will have it through the earth tail. If the tail was not in place continuity is formed via the rigid lug.
But saying that it is not good practice having only one of two screws fixing the plate back.

 

[JohnW2]

As John has mentioned ....

Thanks for confirming everything I said and suggested.

Kind Regards, John