Forever? Twist properly, solder (don't use acid core, use rosin core), cover with heat shrink. It will be fine long after we are both dead...

Image from reddit:
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Google Western Union splice or Lineman's splice for how to do the make-up on this. mbwalker is 100% correct... Non bulky and quite strong.

-Mike

Don't forget to put your heat shrink tubing on before you solder the wires Also, make sure to have it far enough away from the joint that is doesn't shrink to the wire while soldering.

The video is humorous and shows the basic idea. I prefer to make my twist more like the one in mbealker’s pic so it is nice and neat and smooth. Maybe even twisting it slightly less, just enough to tie the wires neatly together. Once they are soldered they aren’t going anywhere.

And for gods sake go to Harbor Freight and spend $10 or so for a heat gun for the heat shrink step.

This was the “officially approved” method we were taught in my first real job as an electronic tech years back.

been known to use these doing one or two splices... i am not going to call it neat tho. It is a lot better then the typical shit you find in games... twisted wires masking tape etc..

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Weller makes a cordless soldering tool that also has a torch attachment. Use this all the time in my work and works quite well. It is butane powered.

I've NEVER done THAT...(except what seems like every single time)

To expand on my original post to the OP, the twist provides the mechanical connection, while the solder provides the electrical connection. Follow that rule, and you'll be good.

A quick comment on the acid vs. rosin core so it doesn't go unnoticed. Acid core (for plumbing) is a big no-no. It can attack the wires over the years. The aggressive acid flux is to help join the copper plumbing where the metal might not be the cleanest. Rosin flux also helps the solder flow, but is safe for electronics.

Also, a lot of the solder you get nowadays (like at Wallymart) is not lead based. It works OK, but the melting point is higher than lead based solder. Noticeably trickier to work with than lead based solder. Lead based (i.e. 60/40) really flows well and is easier to use. Plenty of good choices at Amazon.

If you're a newbie at soldering, grab some junk wire and practice, practice, practice!! A cold solder joint (bad) will have a dull, almost crystallized appearance, where as a good solder joint will be shiny and smooth. To clean any residual flux off, IPA (alcohol) does a halfway decent job. A slightly wet sponge does an excellent job of keeping a soldering iron's tip nice and clean, much easier on the tip than the copper mesh stuff. The mesh can eventually peel away any coating on the tip.

Whew! All that above just to solder two wires together!

Western union for the win.

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