Where to buy long ( 'double') butt crimp connectors

Sure on that? I do ends individually with a rachet tool.

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I'm not an electrician so I've just checked a couple of connectors, both of which *required* separate crimping at each end. Bought here:

Hi Adrian,

Looking at your diyfaq reference, the blue crimps in the illustrations are much longer than mine - they're the sort I want! Are these what you use? Where do you get them?

(The crimps I'm using ha are 24mm long. This is made of the two 6mm plastic ends (where the insulation goes in) and the 12mm central part (containing the metal which gets compressed). My crimping pliers have a thickness of

Cheers

Steve

Thanks Cic. But these are the ones I've got and are not long enough (the compressible part is 12mm - which holds both wires; my crimping pliers (also from TLC) are about the same thickness, so I have to compress the whole thing in one go.

Steve

I got a 'selection box' from screwfix a while back and this was my first introduction to using crimps. the couplers in that are double crimp ones and I did not realised there were single ones. So maybe try screwfix or their cheaper (generally) cousin, toolstation? The ones in the TS catalogue certainly look long enough by the proportions of the flared sections to the narrow part.

hth

Bob

Just seen your further posting on this topic Steve. My crimps are 24mm long and the tool has 9mm jaws and allows a second crimp with ease. I think you could still do this with your crimper. Because the crimp has a central barrier to stop the wire going through too far, the only effective part of the crimp is the one nearest the flare at each end.

I've just done a test one and posted a pic here.

HTH

Bob

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I think you're probably using your crimper too close to the centre of the crimp. The *effective* jaws of the crimper (mine also from TLC) are only about 8mm wide so the outer edge of the tool should be overlapping the outer part of the crimp - close to being in line with the end of the crimp.

My test pieces are almost identical in dimensions with the picture shown by another poster (Bob Minchin) so I think you should try a few more test pieces to get it right.

Cic.

I think you have highlighted the source of the problem. The jaws of my crimper

Thank for taking the trouble to do that Bob. As you will see from my previous post, the problem has arisen as my crimping pliers are wide. They are 11mm. They fit nicely into the 12mm thinner middle section of the crimp, and I assumed this was the correct.way to use them. I was looking for crimps with two 12mm thinner sections. Ah well, you live and learn. Steve

The ones in the picture were one of the cheaper varieties from CPC...

No they're not. There is a division halfway down the crimp. You should only crimp either side of this.

Couplers (of a decent make) are all the same length regardless of colour. I measure it at 28mm. They have a shoulder at either end and you butt the crimper to this. The jaws on mine are 10mm wide. It also came from TLC. Are you sure it is a crimp tool made for insulated crimps? It should have red blue and yellow identifiers by each set of jaws.

Thanks. I've now realised that!

I've just done some accurate measurements on a blue coupler bought recently from TLC and my crimp tool - which was bought some years ago from the same source - but looks pretty well the same as the one in the picture.

Using a decent digital caliper, the overall length of the crimp is 26.7mm.

Taking one apart, the metal bit is 15.3mm

The actual working part of the jaws on the crimp tool is 7.9mm.

Its some considerable time since I bought my first crimp kit (Ampliversal) which came with an instruction leaflet since crimping joints was new fangled then. The manufacturers method was to insert the conductor to the centre stop having just sufficient stripped conductor that the insulation met the inner metal sleeve. A crimp was made such that the conductor was compressed inside the metal sleeve and the outer wider bit of the plastic overall sleeve was crimped so that it gripped the insulation of the conductor core. The procedure was repeated at the other end so a completed joint had four compressed areas, two for the metal to metal joints and two gripping the insulation. We did not have ratchet crimpers but had to ensure that the handles met at a dedicated stop between them. I still use the same method today and the tool is still perfect - obviously made before the accountants got at the design when I see the useless things on the market now!

While we're on the subject, has anyone ever found a source of really small butt crimps - for joining

I'd also love to find some teeny-weeny choc-block for similar wire sizes - the same sort of size as the 0.1" pitch PCB terminal blocks - suppose I could knock up some PCBs with a pair of those back-to-back.

Mike Harrison coughed up some electrons that declared:

Gel crimps from RS - mentioned a week or two back by me :)

butt crimps - for joining

the same sort of size

with a pair of those

I usually use:

or for individual wires (especially if anywhere they may get damp, I use the gel filled Scotchlok crimps:

Thanks for taking the time and trouble to measure.. The crimps I have (TLC) are 24mm near enough, not 28mm. So they are not standardised. Yes - I've got the proper (red/blue/yellow) crimping tool. I've discovered I was doing it wrongly, by crimping at the centre (see other posts in this thread).

In fact, with my the crimping tool 11mm wide, I just have to have its edge flush with end of the crimp, and it's positioned perfectly (a 2mm band in the midlle is not compressed).

Cheers