Joining broken wire

AIUI, in many cases, the door is fitted to the car with the electrics already in the door, then plugged into the loom. Find the plug and you can give yourself extra length to play with.

Steve

RegWorts used his keyboard to write :

Solder and a suitable size of heat-shrink tube, is the smallest joint of reasonable quality, but some overlap of copper will be needed for strength in the soldered joint. The only solution if there really is not enough spare to join them directly, then a short bit will have to be inserted - involving two joints per wire. Doing that would allow you to make the joints, perhaps in a more suitable place than where it needs to frequently flex.

You'll be wanting the right size crimp then, there's very few wire in a modern car that won't go in a decent red insulated butt crimp reliably.

They're good if you're expecting water but otherwise a pain.

Add a short bit of flexible wire to make sure the joint isn't at the point the wire flexes.

Thanks for the speedy replies.

It looks as though an extra length of wire is going to be the best option....and possibly the heat shrink crimp. (I`ve seen these in the Maplin catalogue but wondered how effective they were.)

I was hoping to avoid having to remove the inner panel (again) because it`s a pig to get off without causing damage.

(I used an old credit card and metal scraper........effective ....but I don`t trust the plastic clips will survive too many removals)

Cheers

Reg

Buy the Ratchet crimp tool, your wrists will appreciate it

You can get new ones at most local parts stores. They're fairly cheap. e.g.

You can also get the trim button remover tool for about £1.95 iirc.

Steve

Red crimps are for 1.5mm cable. Plenty smaller than that on cars - even older ones. Although they may 'work' on smaller cables, they won't give a good crimp. A good crimp grips the cable all round - not just squashed onto it.

In both the A-MP/Tyco and RS ranges, a red crimp is designed to accommodate cable sizes from 0.5mm - 1.5mm.

Chris

Just checked on my crimps and it says 1.5 mm but thats the max size it will grab for red

It also says 22-16 which i assume is the gauge size , 22 would be about .64 of a mm 16 about 1.3mm

Just tried a red crimp on .5mm and it seems to grab ok

Or you could have just double-checked on the RS and Tyco websites and saved a crimp...

:-)

Chris

Oh - indeed. But doesn't make a good crimp. Try cutting the plastic off one when using cable at the lower end, and examine it A proper crimp tool produces a heart shaped crimp which grips all round. Those are simply flattened. They work well enough on single strand mains cable which they are designed for - but not on flex at the lower end of their 'spec'. And look truly awful on a car.

Better to splice in an extra bit of wire - solder just the end - and cover with adhesive heat shrink.

If you actuaaly want to test how good it is seeing how much force it takes to pull it off is more useful.

Its down to the crimping tool you use , if its a cheap one then your not likely to get a decent bite , my crimps cost me around £60.00 when i bought them and they work well on stranded cable

Possibly the better option it depends how accessable the wire is though and how close the rest of the loom is and internal finishings .

Not unkown for the ham fisted to burn through other cables or damage the internal finishes with hot toys

We've had this conversation on here before!

In the early sixties I spent some time persuading my employers that crimped connections were the way to go, over and above other forms of termination. I was helped in my quest by an employee of A-MP, who had lots of photographs and other technical data showing that a properly made crimp, used within the range of cable sizes, actually "cold-welds" the wire to the lug.

The crimp tool form is designed to change the shape of the crimp to allow for differing wire sizes, by virtue of the way the lug deforms during the crimp process.

A-MP also guaranteed that if the wire size used was within the maximum of the terminal, the resultant combination would always be capable of carrying the full current rating of the wire, something my employers were dubious about initially.

In over 40 years as an electrical technician, with a fair bit of control panel building involved, I have made many thousands of crimp terminations. These have ranged in size from micro-electronic stuff up to

Some of these terminations were on machines that had similar characteristics of movement, vibration and temperature change that are encountered in a car.

A *properly made* soldered joint will be adequate for wire splicing within a car loom, as will a *properly made* crimp joint. However, from experience of sorting out other people's attempts at repairing their car's wiring, I strongly contend that Mr Joe Average has a better chance of achieving success with the latter rather than the former.

I don't think appearance of a joined wire would be a significant factor in most people's view; in any case, ideally either type of joint will be supported by being tape-wrapped.

Chris (feeling extra nerdy today!)

Dave Plowman (News) wrote on 15/02/2010 :

I suspect these will be control wires and likely smaller than the minimum 0.5mm.

I agree - and a smaller, much neater, much more reliable job.

Not much IME with 0.5mm. Long before the wire breaks. Try it.

Which red blue and yellow pre-insulated crimp tool costs 60 quid?

You can certainly pay that and more for specialised types, though. And I have. ;-)

Absolutely right for the majority of crimps made with the correct tool. But not those red blue and yellow pre-insulated types. The tool simply flattens the crimp. I urge you to have a look at the crimp itself after removing the plastic on small flex sizes. It looks awful. You could do as well with a pair of pliers.

I have. Beats the average amateur soldered joint by a large margin.