FSU - screws won't tighten so unit is loose against wall

[Redbird]

Hi

There is an FSU in my kitchen linked to a 13a socket beneath the worktop for my fridge. However, the FSU itself is slightly loose against the wall, not so much that it is very likely to be a danger but it is irritating and displeases me!

The screws themselves just turn and turn without ever biting properly. Is there anything I can do, other than the drastic action of replacing the metal box set into the wall?

Thanks!

 

[DetlefSchmitz]

Araldite an M3.5 nut behind the lug.

 

[JohnD]

get some new screws.

It is usually the soft, plated brass screws that have lost part of their thread. Take them out and have a look.

 

[Redbird]

Thanks both!

The screws themselves look grand, but I did wonder about what must be a tiny amount of thread on the thin lugs on the metal back box. Araldite & nuts sounds promising...

While I was poking around in there (with the power off of course) I noticed there is no earth going to the metal box, just to the FSU itself. The wee earth screw on the metal back box is covered in a hard blob of cement that has oozed where it is not welcome :-/

 

[Redbird]

... so I suppose I'd better dig that out and add an earth... yawn! Why does a simple job sometimes grow?

 

[JohnD]

you can get a 3.5mm rethreader and try that to improve the threads on the lugs. Give them a squeeze with pliers first.

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[Redbird]

Ooh thanks John! Like this: http://www.amazon.co.uk/Silverline-868714-3-5-mm-Re-Threader/dp/B000NBY9PS

 

[JohnD]

never buy any tool which has the name "Silverline" on it.

 

[Redbird]

Fair enough

I'm not in the habit of buying tools on Amazon either... it was just the first hit on Google! I didn't realise rethreaders existed. Anyway, thanks very much...

 

[Taylortwocities]

never buy any tool which has the name "Silverline" on it.

 

[RF Lighting]

you can get a 3.5mm rethreader and try that to improve the threads on the lugs. Give them a squeeze with pliers first.

View media item 966

Nice to see Mr. Blobby back on DIYnot

 

[Pigeon85]

Self tapping screw?

 

[securespark]

Nice to see Mr. Blobby back on DIYnot

Now, I know I need to lose weight, but that's a bit mean...

 

[plugwash]

While I was poking around in there (with the power off of course) I noticed there is no earth going to the metal box, just to the FSU itself. The wee earth screw on the metal back box is covered in a hard blob of cement that has oozed where it is not welcome :-/

As long as the accessory has provision for earthing the screws (every non-lightswitch accessory i've seen does), an earth is connected to the accessory (as you say it is) and the backbox has at least one fixed lug (most do) then the screws holding the accessory to the backbox are considered to provide adequate earthing of the backbox.