Strain relief for spade terminals

[Jodes]

I'm worried about putting spade crimp terminals onto a cable for use in a vehicle.

I'm worried about the conductor strands at the connector flexing and breaking over time.

There seem to be terminals with one, and with two crimping clamps - so one will be for the conductor alone, and the other for the insulation+conductor.

Would it be acceptable to use ones with a single crimp section?

For example, using 16A thin-wall multi-strand single cable, to connect with an insulated terminal onto a pole of a lighter socket.

I was considering using heat-shrink sleeving on top of the insulated terminal, extending to part of the wire, to provide strain relief. Is this necessary? Is this enough?

Thanks again

 

[uksparks]

I'd probably use the twin clamp type and a nice but of glue lined heart shrink to make it look good as that goes quite firm when the glue is set.

 

[Deleted member 26818]

If you're using non-insulated crimps, make sure you have the correct crimper and good quality crimps.
I wouldn't worry about strain relief, unless what ever you are crimping to is going to be moved around a lot.

 

[Jodes]

Thanks - but why would using non-insulated crimps mean the crimps/crimper should be better?

 

[uksparks]

I was just going to say that about it moving about, ideally no termination should be subject to strain.

 

[uksparks]

Insulated crimps of that nature just compress against the conductor, where as if you have non insulated crimps, the twin type, the crimper tool bends the little flames over etc.

 

[Jodes]

I was really more thinking about vibrations in the vehicle - besides the vibrations, there wouldn't really be any movement.

 

[Jodes]

Insulated crimps of that nature just compress against the conductor, where as if you have non insulated crimps, the twin type, the crimper tool bends the little flames over etc.

Ah ok, I get it - I didn't realise uninsulated crimps are always the twin type - thanks!

 

[uksparks]

I think you can get single ones not twin, let me look.

 

[Marvo]

Uninsulated;



They also make separate insulating covers

 

[uksparks]

That's a perfect example Marvo, they also look nice with the clear boots on.

 

[Deleted member 26818]

The picture Marvo has posted shows a crimp which is intended to be used in a multi-plug.
The inner core of the wire is gripped, and the insulation is gripped whilst also being pierced by the ends of the tangs.
A cheap crimper might form a crimp where the insulation is gripped and pierced, but the inner core loose. Alternatively, it might form a crimp where the inner core is gripped, but the insulation is loose.
It some cases the insulation is not pierced, in others it is pierced to such an extent, that the wire is likely to snap.
Cheap crimps, generally use less material, so often the tangs are too short to pierce the insulation, and sometimes the material is not thick enough to grip either the inner core or the insulation.

 

[uksparks]

How many of these terminals have you got to crimp? If it's just one, I would just use a Pair of pliers.

 

[Jodes]

It's just a few to start with, but I may end up doing more work on them and I'd like to get into the habit of doing a good job, I've got a basic crimping tool but I don't think it would make the crimp tags fold like they should. (Picture below). What kind of crimp tool would do the best job?

 

[telectrix]

one like this:

Crimper for Crimp terminals/ professional Ratchet action Crimping Pliers | eBay

 

[jonny705]

I have a friend that is a Avionics engineer, he was telling me crimps were the only thing they use when they terminate electrical wires.

Was saying that screws /bolts are never used because vibration would ultimately cause them to fail .

Although his crimping tools are serious quality , and have to be calibrated quite regularly.

Since then have happily used them, just like other people have advised , don't get cheap ones or fittings - but if they are good enough for the aircraft industry , a car will be fine :smilewinkgrin:

 

[Jodes]

I suppose the only remaining question is how can I tell if crimp terminals are good quality? I haven't seen any local avionics stores! Sort of surprising given I'm near Biggin Hill lol. I would go for branded items, but I've learnt not to trust brands as far as I can throw them.

 

[uksparks]

I've not got these ones but I would highly recommend Knipex, they will be about £110. I've got a few of the other type of crimps and they are if exceptional quality.

 

[shanky887614]

£110 for a set of crimpers? they better come with a calibration cert for that kind of money.

i would recommend tri-rated bs6231 cable or yy, its a lot more flexible than say 6491b so it wont snap, 6491b has very fine strands so will be fine

 

[Deleted member 26818]

There's a company called Vehicle Wiring Products where crimps and crimpers can be purchased online.
Vehicle Wiring Products Ltd Suppliers of Auto Electrical Parts