Self amalgamating tape

[Licklieder]

On the matter of self-amalgamating tape, are all tapes made equal? Screwfix sell an unbranded one that is described as "Suitable for jointing, splicing and repairing cables, hoses, plastic and metallic tube" but with little information beyond that. Then there's the likes of 3M scotch 130C, which has an extensive product data sheet ( https://www.cablejoints.co.uk/upload/Scotch_130C_Tape.pdf ) including rating to 69kV.

Is the screwfix one safe to use on electrical cables, or should i be looking for tape like the 3M one?

 

[Simon35]

Where would you use self amalgamating tape to do any sort of electrical repair in a domestic setting?

 

[Licklieder]

I'm not sure i have anywhere in mind per se - this is more of 'trying to understand' question (prompted by EFLImpudence's comment on my post about insulating tape). Are you inferring that there is no use for S-A tape in a domestic setting ?

If i were to think of a use in domestic electrics, perhaps if using crimp butt joints on T&E in a maintenance free setting; where there is not enough exposed cable (say in a backbox) to use heat-shrink to extend the outer PVC to cover the joint.

 

[seasickstevie]

Last time I used self-amalgamating tape, it just wouldn't 'hold' together. It's obviously not meant to be sticky like other tapes, but it just literally fell off!

Maybe there's a knack to it.

 

[davelx]

Last time I used self-amalgamating tape, it just wouldn't 'hold' together. It's obviously not meant to be sticky like other tapes, but it just literally fell off!

Maybe there's a knack to it.

You have to remove the backing and stretch it hard a few times first, and then keep it slightly stretched it whilst wrapping.

 

[seasickstevie]

You have to remove the backing and stretch it hard a few times first, and then keep it slightly stretched it whilst wrapping.

I did of course remove the backing tape . Thanks just the same.

Maybe I need to try more stretching.

I got the feeling, that maybe it has a limited life / use-by date. (there isn't one on it).

It has admittedly been in a drawer for a couple of years.

 

[davelx]

I've just tried a length of mine which is at least 5years old and it's fine. You need to stretch it quite hard a dozen or more times so that it gets a little warm.

 

[EFLImpudence]

I believe the instructions (yes there are instructions) which come with it state you should stech it to three times its length while wrapping it round whatever you want to insulate.
You can then make it as thick as you want by more turns.

As the name suggests - after a while (not sure how long) the tape layers amalgamate and become like one tube of rubber (much like heat-shrink but more versatile) which is very difficult to get off without cutting.

So - it could be used for covering a soldered repair but I presume heat-shrink would be used, although no one seems to solder these days - using unsuitable crimps instead.

 

[mattylad]

I use it on aerial installations, wrapping it around joints etc. The screwfix stuff has been good for a couple of years so far.
Not sure where I'd use it for electrical joints, i'd prefer insulating tape for that

 

[Licklieder]

- using unsuitable crimps instead.

I'm curious - I thought crimps were one of the acceptable ways producing maintenance free joints (the other being to solder. why do you say they're unsuitable ?

 

[EFLImpudence]

Suitable compression fittings are allowed.
That is - properly fitting proper crimps using proper crimper.

The squash flat rubbish ones are not actually suitable.