Flux gone and table space tight, alternate to solder?

When I consider that I do use connectors of various kinds... they tend to stay working.

I make breadboards or twisted wire circuits work to test them so I wonder about twisting wires together, lay the twist along the wire and apply silicone (what some wire splices do) to displace O2 or heatshrink tubing or both.

Question being, if the join is never flexed, how long might it last?

Likely to last your lifetime. I have twisted electric fence wires that have lasted 15 years with no solder. And they are always open to all the weather elements.

Twisted wires (wrong name) "guarantee" that at least one string (actually a "strand") is still connected. And they are more flexible (and they are better for RF signals due to surface).
But for my experience: twisted wires (totally wrong term: better: stranded wires) in screw sockets (esp. in breadboards) are very tricky: it can happen that some stranded wires break, are not connected or even create shorts when strands hanging around. When you need a minimal wire gauge and not all stranded wires are connecting - it is like a much smaller wire: so, make sure, all strands are connected. Do not cut strands just because they do not fit into pin (or connector).

So, for my experience: twisted wires (actually a wrong name: it should be "stranded wires" - a twisted wire is something else, e.g. to twist two signal wires around each other =
"Twisted Pair" as a symmetrical connection) - should be "terminated" like a solid wire (e.g. solder the ends). But soldered wire ends in a screw terminal create weakness over time! (lose contacts and tin soldering is not long lasting, tin is aging).

I prefer to "crimp": put the stranded wires in to a pin and you crimp it. So, all strands ("wires") are inside the pin and no tin used (not aging) and almost all strands remain connected with the "crimped pin" - forever.

Probably past the date of your expiration.
:woozy_face:

If you use a flex wire on a machine which shakes a lot - it will break before "you expire"
(e.g inside a washing machine).

It is a mechanical question:
a) how do you connect the "stranded wire" into a socket (screw terminal)?
(best it: crimp the ends of wires with a solid pin and then screw it)
b) how do you do "stress relief"?
(don't let bent so much even a stranded wire in use, esp. with short radius: they will break as well with stress, every strand after each other)

If you never touch such wire, it never bends - even a solid wire would work fine.
Stranded wires are used for wires in motion: how much motion over time - do you know?

I will just offer my opinion as your question is of interest to many:

An initial good, non-soldered or non-crimped, low-voltage electrical connection is likely affected predominately by temperature & humidity. Assuming a constant ambient temp and low-humidity, the joint life-time is "long."
But, even small temperature changes and high-humidity such as in a basement lab will affect the quality of the connection and will shorten the life of a "good" connection based on:

  • the current through the mechanical joint
  • the voltage across the mechanical joint
    Explanation: The higher the current, the higher a delta-temp created by any resistance and likely an advance of increased corrosion due to humidity. Any temperature rise indicates resistance at the connection and thus a voltage drop. The voltage drop is particularly of concern in common grounds. Pure logic lines are very low current and not particularly of concern, but power lines can create problems by creating logic-level offsets relative to different parts of a complete circuit.

Personally, I have several small boxes of "prototyping parts" and these are the ones I grab to "tact solder" for testing (battery powered iron.) Otherwise, I use a high-quality solderless breadboard for high-value one-of-a-kind sensors and modules.

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These things last for ages.

Hi,

These are far better.

Tom.. :smiley: :+1: :coffee: :australia:

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A twisted copper wire joint without some type of retention will fail over time as the copper relaxes. It generally will start to increase in resistence as the connection corrodes internally. This is also why Al/Cu junctions need special connectors, the Al and Cu deform and relax differently, causing rising resistence and eventually electrical fires after ~20 YEARS!

Mil spec says connections must be "gas tight", ie metal wiping metal, to form an eutetic, gas tight, bond. Without crimping, soldering, a wire nut, or SOMETHING, to provide compression, the connect WILL fail and is un-acceptable for anything but a temporary fix to be replaced as soon as the proper equipment is available.

When I strip jumper wires and twist the ends together, that is twisted wires.

Corrosion of dissimilar metals usually has water or humidity in on the act.
At least that's what does fast work on aluminum siding and gutters put up with steel nails. With T6 aluminum nails, no problem.

A heatshrink straitjacket at minimum is the restraint, no loosey goosey stuff past breadboarding. I want to get some WS2811 displays out, Ho-ho-ho!

I crimped a lot of cables in the 80's and 90's. I had bags of pins and bodies. Now, I have solid copper wires maybe 18-20 ga and assorted dia heatshrink tubes.

That is the reason for "gas tight", water vapor cannot infiltrate.

Don't forget, the wires expand when heated by current then contract when cooled. Over a long time that can loosen the twist and "snowball" into FIRE. I've seen that happen many times with wire nuts.

I don't trust wire nuts but if I made a living on service calls....

I've yet to see a good crimp fail and I have seen how tight heatshrink gets which hasn't been addressed. It's irradiated PVC tube that shrinks down hard if you match sizes right. Love the stuff.

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