And even then, we still get errors in the connections... specially as we're moving away from DC discretes (keylines) and low speed busses to high speed.
Even the RS485 and RS422 busses are subject to imperfect connections that cause impedance mistmatches on the line... this results in data dropped.
I'd say that 50% of the avionic failures I've seen were caused by faulty connections, very often during take off when high speed vibration is at its worst.
Correction... that's for air planes, helicopters are different... never mind spacecraft.... the vibrations there are *** crazy and the take off is a lot longer.
For many years, the avionics industry refused to use optical fiber.... then airbus stepped in... fearless Germans... sure enough, I was called cross country to do a deep dive on a brand new system we'd just installed on a Spring Works aircraft.
To add my tidbits... for low power ( 2 < x < 18 VDC ) DC connections, simple crimping by itself tends to be OK. AC signals are a different story. They require very good cimping to ensure proper impedance matching. The echoes of an impedance mismatch will affect the signal - data, even under static lab conditions ( no vibration ).
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Yes I have them by Molex, Klauke etc. Cost an arm and a leg and possibly one has to do dishonorable things to get them.
I tell you, your virginity is worth a lot more than that Molex tool!
In the mil spec world we build wire harnesses. The only time I've seen wiring in an existing airframe is when installing test equipment ( or testing new components ).
just remembering somebody once stole my little Fokker "finish code book", where they magically did put ALL the A/C wiring connectors info, pins (including color codes), and crimping tools numbers and settings to be used for different AWG together in a little booklet you could put in your pocket.😉
Did you crimp the wires to a connector? Molex or so... or did you crimp directly to the board? I don't think crimping directly to a board is particularly cost effective in avionics.
The US Navy used to have a standard for test fixtures (and some ship electronic racks) where the boards would plug into a back plane and the back of the backplane used wire wrapping.. with connectors for external wire harnesses. But that was in the 80s and mostly for low speed connections.
I'm currently programming an old VME chassis, but the high speed data busses and RF data goes out the front panel of the boards.
I have been told for years that a cheap crimping tool is worth what you paid for it if you think it will suffice by itself.
To each his own.
Think of a PCB where the traces for external connections are extended from the land of the board and the tiny crimper one would use to connect to a wire? Would be neat. Would have to have some kind of powerful servo motor since hand power would not work very well.
There is always the welding option for the well heeled.
I prefer compression, too. But sometimes it is not possible and simply not as good as a soldered connection. in most of the connections DIYAudio folks make.
To each his own.
Think of a PCB where the traces for external connections are extended from the land of the board and the tiny crimper one would use to connect to a wire? Would be neat. Would have to have some kind of powerful servo motor since hand power would not work very well.
There is always the welding option for the well heeled.
I prefer compression, too. But sometimes it is not possible and simply not as good as a soldered connection. in most of the connections DIYAudio folks make.
That's just it. What do we need to accomplish in audio? Certainly the best connection promises the best results, but we would not go to a14 metric ton hydraulic crimper for this purpose. That is absurd. Just as absurd is to expect a small cheap handheld (maybe pliers) tool to accomplish the needed connection either. Whatever this means>>> the proper wire being crimped with the proper connector and proper tool, seems reasonable to me. Surely there are a few tricks that can make a more solid holding crimp, and in some cases a thin coat of De-oxit or some such to help ensure the duration of the crimp against corrosion if that is a concern.
Before any of this begins, the process of 'perfectly' stripping the wire can have a great effect on the resulting quality/durability of the connection.
Before any of this begins, the process of 'perfectly' stripping the wire can have a great effect on the resulting quality/durability of the connection.
Let alone touching the bare copper wire.
BTW having experience with both normal and hydraulic crimping tools I think the hydraulic/electric ones are not a guarantee for good crimping per se. They are convenient. TBH one of my favourites for wire ferrules is one of the cheapest for 13 Euro. In quality of crimping practically equal to my Weidmüller.
BTW having experience with both normal and hydraulic crimping tools I think the hydraulic/electric ones are not a guarantee for good crimping per se. They are convenient. TBH one of my favourites for wire ferrules is one of the cheapest for 13 Euro. In quality of crimping practically equal to my Weidmüller.
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I know this isn't mission critical stuff, but my $45 OPT crimper for insulated automotive terminals crimps well enough so you cannot pull the terminal off the wire, as long as the terminal itself is good quality (made from copper thick enough to maintain the crimping pressure). I've cut through the crimped area and the copper almost looks like its solid rather than stranded.
Like I say though, I generally solder on audio stuff, even if I use crimp terminals, such as onto the back of IEC sockets.
I will admit I use cheap solder seal connectors occasionally, which is no different than just soldering the wires together (arguably worse even).
I purchased my car used 5 years ago. It came from the factory without fog lights, but the wiring was there. The connectors were severely corroded from dangling under the front bumper for years. I purchased a flog light kit and new pigtails. I used solder seal connectors to attach the pigtails. They're still perfectly fine after almost 5 years of extreme temperatures, salt spray, and vibration.
I purchased my car used 5 years ago. It came from the factory without fog lights, but the wiring was there. The connectors were severely corroded from dangling under the front bumper for years. I purchased a flog light kit and new pigtails. I used solder seal connectors to attach the pigtails. They're still perfectly fine after almost 5 years of extreme temperatures, salt spray, and vibration.
In my 50+ years experience of electronics and vehicles, I have lost count of the number of failed crimp connectors, but can count the number of failed solder joints on one hand.
There's so much nonsense in that video that the correct become difficult to isolate - or believe - even when you know!
Also, to the British ear, 'sodder...' really grates...
There's so much nonsense in that video that the correct become difficult to isolate - or believe - even when you know!
Also, to the British ear, 'sodder...' really grates...
The wire is stiff right where it enters the connector too. Soldering it just moves that point a little farther away. And I always heat shrink which provides some strain relief.
In the climate I live in where snow and rain and road salt are common, a failed connection from corrosion wicking into the wire is more common than from a fracture.
Obviously not an issue in a stereo, but it also gives peace of mind that the wire isn't going to pull out from a bad crimp.
Never had a failure or a corrosion problem with a crimped connector for pre amps, power amplifiers or loudspeakers. Have had failures of soldered small signal path wires.
It is a kind of tricky thing, stripping wire. The smallest nick in the conductor(s) will likely result in failure. I suppose that it is like cutting glass, even though they are two different materials. Just about anyone that I have ever witnessed stripping wires, leaves a 'mark' right at the cut of the insulation. Damned near invisible but there it is.
Then there is the connecting method used. Soldering fine wire is another setup for trouble. Temperature, solder used, and maybe even a tiny bit of flux in some cases. Timing is everything here. And need I mention the proper tip? SMD soldering was way harder until I used the right tip. Same with fine wire. You go the other direction by way of wire size and the components all change. All of this not to mention some of the damned near impossible to solder wire that exists out there.
Crimping is no different than the above right from the start. Everything involved has an effect on the outcome, and most of the time 'that's good enough' is completely wrong.
It doesn't happen often enough, but I prefer to wire wrap when it is possible. As usual, there is a method to it as well.
When applicable, I sure do like the old solder turret where the wire can have a good mechanical connection first and then be soldered after.
Then there is the connecting method used. Soldering fine wire is another setup for trouble. Temperature, solder used, and maybe even a tiny bit of flux in some cases. Timing is everything here. And need I mention the proper tip? SMD soldering was way harder until I used the right tip. Same with fine wire. You go the other direction by way of wire size and the components all change. All of this not to mention some of the damned near impossible to solder wire that exists out there.
Crimping is no different than the above right from the start. Everything involved has an effect on the outcome, and most of the time 'that's good enough' is completely wrong.
It doesn't happen often enough, but I prefer to wire wrap when it is possible. As usual, there is a method to it as well.
When applicable, I sure do like the old solder turret where the wire can have a good mechanical connection first and then be soldered after.
This topic creeps its way into a lot of conversations. Connection methods may be/are application specific.
For the vast majority of what's discussed in these forums, if a connection fails, it's likely user assembly error (poor technique) or poor choice of tools / parts. At least that's anecdotally what I've seen. It seems rare that we see the "wrong" overall methodology whether to crimp and/or solder. Sure, I've seen bare and soldered stranded wire stuffed into "Euro-Blocks", but that's not what I think we're talking about here.
So, what would-be builders may want to ask themselves is "Which method am I least likely to F-up?", because both crimping and/or soldering are perfectly applicable and reliable for what we usually do around here.
For the vast majority of what's discussed in these forums, if a connection fails, it's likely user assembly error (poor technique) or poor choice of tools / parts. At least that's anecdotally what I've seen. It seems rare that we see the "wrong" overall methodology whether to crimp and/or solder. Sure, I've seen bare and soldered stranded wire stuffed into "Euro-Blocks", but that's not what I think we're talking about here.
So, what would-be builders may want to ask themselves is "Which method am I least likely to F-up?", because both crimping and/or soldering are perfectly applicable and reliable for what we usually do around here.