Cut wire help please

[dybleah]

Hi,

I've cut through the wire that supplies my flat's video intercom. It was a chunky wire with quite a few small individual wires within. I was hoping to create a bit of slack on the wire, then join the ends together using a ?mini-junction box ??

Could I ask what is the best and sleekest option to join the 2 ends together? I prefer not to use things like solder if possible.

Many thanks

View media item 82851

 

[bernardgreen]

Boot lace ferrules and heat shrink sleeve.

With care it is possible to put one end of the wire in one end of the ferrule and the other end of the wire into the other end of the ferrule and then crimp the ferrule. This requires a couple of mm of slack in the wire.


Slide the heat sink onto the wire BEFORE putting it into crimp.

 

[davelx]

That's burglar alarm type cable - the cores are very thin and it's quite difficult to get a good crimp even with a soft bootlace ferrule. If you want to try this way, I'd slide the ferrule onto one end, th eheat shrink onto the other, twist the stripped cores together and then crimp the ferrule over them, then heat shrink over that.

Twisting, soldering and heat shrink is really the best way, but you could use an alarm junction box which is designed for that size wire:


http://www.ebay.co.uk/itm/like/1114...1=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0

 

[dybleah]

Thanks so far for replies.

So I'm quite attracted to several ideas: a) choc block b) inline splicers c) crimps. Few questions, as I'm quite concerned about the tiny nature of the wires and safety (Don't want anything burning/melting!)

1) Do I still need to heat shrink/electrical tape each one of my 10 cut wires?

2) The choc blocks are rated by amps - Does this also affect their size?

3) For a basic Comelit video intercom, what ampage should I be using? I was thinking maybe the lowest 3amps? - http://tinyurl.com/o2fqbft

4) Will these splicers be ok for my wires (which look like they are smaller gauge than standard bell wire)? - http://tinyurl.com/m5yccdp

Thanks so much guys!! =D

 

[winston1]

Hi,

I've cut through the wire that supplies my flat's video intercom. It was a chunky wire with quite a few small individual wires within. I was hoping to create a bit of slack on the wire, then join the ends together using a ?mini-junction box ??

Could I ask what is the best and sleekest option to join the 2 ends together? I prefer not to use things like solder if possible.

Many thanks

View media item 82851

What is your objection to solder? It is the best way.

 

[bernardgreen]

My objections to soldering alarm type cable are

[a] the wire is often not tinned ( good to solder ) but instead has an anti corrosion coating ( not good to solder ) designed to suit screw terminals and crimped joints

the insulation melts when the wire is heated to soldering temperatures.

The cable the OP has cut appears to be alarm type cable used for the door intercom system hence my suggestion to use crimp ferrules.

 

[Adam_151]

I must admit I've never had any problem soldering alarm cable.

If there's any kind of coating, I assume it soon burns off with the heat, although I will say that I am still using the old 60/40 , so contamination is perhaps a little less likely to cause problems than with lead free. If the insulation recedes a little with the heat (and its only a little) then if you have put a decent sized piece of heat shrink on then it will cover it

 

[dybleah]

Because the alarm wire is so thin (they are also stranded), I'm finding it difficult to find the right size of the ferrule/crimps. They seem to go down to 1mm squared but I think these wires are less than 0.5!

Help much appreciated, thanks

 

[bernardgreen]

As a starter

http://www.rapidonline.com/design-technology/uninsulated-bootlace-ferrule-16mm-100-33-1138

http://uk.farnell.com/multicomp/e0206-lightblue/ferrule-insulated-0-25mm-pk100/dp/9972196

check the sizes, they can be a loose fit before they are crimped which helps to get the wires into the ferrule but not too loose if you are using pliers to squash rather than crimping with the correct tool.

 

[flameport]

1) Do I still need to heat shrink/electrical tape each one of my 10 cut wires?
2) The choc blocks are rated by amps - Does this also affect their size?
3) For a basic Comelit video intercom, what ampage should I be using? I was thinking maybe the lowest 3amps? - http://tinyurl.com/o2fqbft
4) Will these splicers be ok for my wires (which look like they are smaller gauge than standard bell wire)? - http://tinyurl.com/m5yccdp

1. They all need joining and insulating separately.
2. Yes, larger rating is physically larger. All are likely to be too large for such thin wires.
3. Lower than that - most door systems are 12 volts and the current is mA rather than A.
4. Perhaps, although 10 of those will require a fair sized box on the wall to contain them.

The sensible answer is to solder the wires, far neater, much quicker than terminal blocks and if done properly, would result in a finished joint only slightly larger than the cable itself.

 

[dybleah]

If I use ferrules, they looks like they terminate a wire. If I have 2 ends ferruled, then how do I join them together?

I was thinking of not using a box on the wall, but just digging out a sufficient hole, then stuff the wires (protected by electrical tape) into the hole, and use filler to cover over. I will never need to access them again if they are working.

 

[bernardgreen]

Untitled

• bernardgreen
• 27 Sep 2014
• 1

I used different colours taken from 8 core alarm cable to illustrate the method

 

[dybleah]

Thank you for the pic!

So I just place each end into the same ferrule and then make sure the ends are within the metal part of the ferrule. Then simply use pliers to crimp?

 

[Tony13579]

Because the alarm wire is so thin (they are also stranded), I'm finding it difficult to find the right size of the ferrule/crimps. They seem to go down to 1mm squared but I think these wires are less than 0.5!

Help much appreciated, thanks

I am a retired BT engineer. I have a box of crimps. Designed for 0.5mm wire
If I couldn't get the slack I would let in about 3" of wire and put a crimp each end. If you PM your addressing will post you som free of charge.

I'm my opinion screw connections will give trouble. Crimp or solder is the only option.

 

[dybleah]

Thanks so much for the offer. I actually have a friend who has an assorted box of these.

-In your opinion, for the wires shown in my first photo, what size should I use?
-Do I overlap the wires/twist them first and then crimp them?
-If I can't overlap the wires due to lack of slack, can I just place the wires into the ferrule and as long as they touch some of the ferrule's metal, it should work?
-Can I omit a crimping tool and just use a set of pliers?

Thanks again