Soldering gun, not iron.

[Martin 100Participant @martin100]

Posted by Michael Gilligan on 12/04/2017 11:07:34:

Given the original poster's nom de plume, and the stated intention … is it unreasonable to assume that the job might require the use of Bullet Connectors, of the type which served us well for several decades ?

Even the original bullet connectors used by Lucas for a few decades were actually crimped not soldered, with suitable contact grease in the couplers they will last for a considerable length of time in a salt free environment

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Martin 100 on 12/04/2017 13:05:20:

Posted by Michael Gilligan on 12/04/2017 11:07:34:

Given the original poster's nom de plume, and the stated intention … is it unreasonable to assume that the job might require the use of Bullet Connectors, of the type which served us well for several decades ?

Even the original bullet connectors used by Lucas for a few decades were actually crimped not soldered, with suitable contact grease in the couplers they will last for a considerable length of time in a salt free environment

 

.

Interesting comment, Martin … I must see if I have any original wiring tucked away in the shed.

Soldering [whether original or not] is certainly very common practice.

**LINK**

http://www.a7a10.net/forum/index.php?topic=4832.0

I do, however, bow to your wisdom.

MichaelG.

.

Edit: I'm on a 'bus journey at the moment, but this is what I remember Lucas Bullet Connectors looking like.

https://goo.gl/images/H0cLGw

Edited By Michael Gilligan on 12/04/2017 13:28:41

[JasonBModerator @jasonb]

You can buy bullets specifically for soldering as well as ones that can be crimped/soldered. My usual source of cotton braid insulated wire does them , crimp/solder ones on the first page.

Edited By JasonB on 12/04/2017 13:24:13

[Geoff TheasbyParticipant @geofftheasby]

When I worked in satellite communications, my chief engineer didn't like crimped coaxial connectors, on the grounds that he couldn't dissemble them to see how well they were put together. Martin 100 is right, but the existence of cheap tools and badly-assembled connectors stems from the fact that a decent quality ratchet crimp tool costs upwards of £200, which for a single purpose tool makes it difficult for a small manufacturer to justify.

Geoff

Edited By Geoff Theasby on 12/04/2017 13:31:04

[Neil WyattModerator @neilwyatt]

A properly made crimp connection cold welds the wire into the connector.

Not a lot of people know that.

Neil

http://www.researchgate.net/publication/3620859_Concerning_cold_welding_in_crimped_connections

[modeng2000Participant @modeng2000]

I did!

[peak4Participant @peak4]

Posted by Mike Poole on 11/04/2017 15:34:00:

Wire wrapping does seem to have fallen by the wayside, I had a fault on a robot once where I had to get the entire card cage out to access the backplane which was wire wrapped, turned out that the wire was too tightly pulled against one of the posts and had shorted out, took seconds to fix but half a day of diagnosis and dismantling. I think wire wrapped backplanes have fallen out of use for a number of reasons, multi-layer PCB backplanes with plated through holes are much less labour intensive and equipment seems to be more modular with either ribbon cable interconnections or fast serial links. LSI has also put much more onto one board so racks of cards are less common.

Mike

Still used pretty extensively in telecomms Mike; I'm pretty sure your internet connection to write that will have gone through a number of wire wrapped joints; (if you've got copper broadband anyway).

I can remember my first wiring job when I joined the GPO involved 100 wire cable in twisted triples and pairs. The guy I was working for wrapped the first colour code's worth and told me to get on and finish the rest.

Some considerable time later, one of his colleagues came up behind me and said words to the effect of " nice neat work, but you've got that colour code reversed."

"No" says I, "it's the same as all the rest"

It was at this point we both realised that the chap who showed me how to start the job couldn't remember his colour codes.

100 wire blocks, at 10 blocks per vertical row, and Ron only arrived as I was completing the last block on vert-3.

That will be 3000 wires to find some slack and re-terminate then; oh how we laughed.

I got quite good at stretching wires over the next couple of weeks.

Edited By peak4 on 12/04/2017 19:50:07

[vintagengineerParticipant @vintagengineer]

I always use crimped terminals and the solder is only used to ensure a good electrical connection and never allow it to wick up the cable.

[norm nortonParticipant @normnorton75434]

I agree with those who say – Never Solder if the Copper Wire will be subject to vibration.

I once soldered some connections on a magneto ignition on a racing motorcycle – an earth wire broke next to the solder after two laps. Boyer made electronic ignitions for motorcycles in the 1980s and hundreds of units failed on Norton Commandos when the wires fractured where they left the PCB pickup. A old Marconi engineer told me that soldering wires was forbidden anywhere on the missiles they produced because of the massive vibration..

My interpretation of this behaviour is as follows: Stranded copper cable is in a semi-annealed (semi-hard) state as supplied. When you solder it a weak annealing is applied to the copper in contact with molten solder – this effect ceases some small distance (1mm ?) beyond the solder penetration. As the wire vibrates in use the movement is concentrated at the most flexible (annealed) point within 1mm of the solder penetration. This point rapidly work hardens and fractures.

If anyone has a better explanation I will be pleased to hear it, but the concept works for me.

Norm.

[Mike PooleParticipant @mikepoole82104]

I was amazed at the telecom cable that had all black wires apart from one,the guys installing it explained that you need to strip a long enough length that the lightly twisted pairs can be seen, then starting at the white you work round and round the cable until you get to the final pair. I could see that going pear shaped if I had to do it.

Mike

[Author]

Posts