3 ms·

They sure did make old electronics pretty. At least sometimes, as in the case of this device that probably cost as much as my car. I'm curious about the solde

They sure did make old electronics pretty. At least sometimes, as in the case of this device that probably cost as much as my car. I'm curious about the soldered wires, though. Especially in a device intended to be used in an airplane. No concerns about brittleness? I was under the (probably mistaken) impression most vehicular wiring was clamped or crimped these days for that reason. Maybe those aren't really soldered, but just look kinda like it?

dboreham 4y ago
A crimp is done to a connector so you have to consider the reliability of the connector+crimp. Those soldered wires are direct onto the terminal so no connector.
- rootusrootus 4y ago
  I was thinking it might be specific to the use case, for sure. And maybe these are solid core wires, I can't really make it out from the picture.
madengr 4y ago
Crimping on cars is probably just to save money, and some of the wire they use is garbage. Solder is pretty soft, especially lead based. Silver solders are more brittle and we don't use them for high reliability applications. Gold also has to be removed as it will embrittle the joint. For wires soldered to a PCB you can stake the wires with an electronics grade RTV, then bundle with twine, staked with epoxy. I have used low-outgassing RTV for space applications that costs $600 a tube.
blamazon 4y ago
One possible explanation: leaded solder is more elastic than non-leaded. (less brittle) Modern mass produced products generally have had lead engineered out of them, including in the solder. One popular product specification in this domain is RoHS, the EU Restriction of Hazardous Substances Direction, which largely bans lead and 9 other hazardous substances: https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Subst...
- addaon 4y ago
  Although note that avionics fall under the "transportation" exemption, and RoHS does not apply. That said, the supply chain has moved largely towards RoHS compliance, so some avionics inherit that for supply chain simplicity. Some don't; there's a cottage industry reballing BGAs from lead-free to leaded solder for aerospace applications.

dboreham 4y ago

A crimp is done to a connector so you have to consider the reliability of the connector+crimp. Those soldered wires are direct onto the terminal so no connector.

rootusrootus 4y ago
I was thinking it might be specific to the use case, for sure. And maybe these are solid core wires, I can't really make it out from the picture.

madengr 4y ago

Crimping on cars is probably just to save money, and some of the wire they use is garbage. Solder is pretty soft, especially lead based. Silver solders are more brittle and we don't use them for high reliability applications. Gold also has to be removed as it will embrittle the joint. For wires soldered to a PCB you can stake the wires with an electronics grade RTV, then bundle with twine, staked with epoxy. I have used low-outgassing RTV for space applications that costs $600 a tube.

blamazon 4y ago

One possible explanation: leaded solder is more elastic than non-leaded. (less brittle) Modern mass produced products generally have had lead engineered out of them, including in the solder. One popular product specification in this domain is RoHS, the EU Restriction of Hazardous Substances Direction, which largely bans lead and 9 other hazardous substances: https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Substances_Directive https://en.wikipedia.org/wiki/Restriction_of_Hazardous_Subst...

addaon 4y ago
Although note that avionics fall under the "transportation" exemption, and RoHS does not apply. That said, the supply chain has moved largely towards RoHS compliance, so some avionics inherit that for supply chain simplicity. Some don't; there's a cottage industry reballing BGAs from lead-free to leaded solder for aerospace applications.