I think it should be noted that properly splicing wires using solder and an adhesive heat shrink is far superior to using a basic crimp with automotive store tools. Lineman splice is the way to go
See page 71 of attached Nasa STD 8739.4a
DIY Wiring Tools? (1 Viewer)
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I think it should be noted that properly splicing wires using solder and an adhesive heat shrink is far superior to using a basic crimp with automotive store tools. Lineman splice is the way to go
See page 71 of attached Nasa STD 8739.4a
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^Must be the new electric version.
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Western Union splice is the bomb!! Linemans for you younger whipper snappers! @Somebodyelse5
That NASA document doesn't say that a solder joint is superior to a crimp, and is careful to mention in multiple locations that solder joints are more brittle and prone to breaking from flexing and stress. The only pros they really mention are size and weight.
From wire harness manufacturer CAI:
Crimped connections are more flexible, heat-resistant and vibration-resistant than soldered ones which have greater potential for wire fatigue and stiffening. Crimping is often more consistent than soldering, which can vary according to method or technician. Meanwhile, the crimp-on process is simple, quick and easy to repeat when you know what you’re doing. Properly crimped wire strands can create a “cold weld” in which the pressure is so great that the metals and their oxide layers form on a micro-level. That’s why crimping is the technique of choice in industries, such as aerospace and automotive, which demand the strongest, most reliable connections and can’t risk the degradation of filler metals.
I will still stand by saying in an automotive context, 99+% of wiring should be crimped, and solder should be used sparingly and only when crimping is not possible or the wire connection is very well protected from flexing and vibration. Solder should almost never be used on sensor wiring as the solder adds resistance and could affect the signal
I think we agree way more than you may think 
I crimp my terminations... lugs, plugs, connectors.... I am not, by any means, suggesting that soldering is superior across the board.
I'll still say that in a mid span splice or wire repair situation, I will go for a soldered lineman splice with an adhesive backed heat shrink over a standard automotive crimp. From a mass perspective, the butt crimp is heavier and you now need to secure the wire or risk it flopping around. Sure you get a stiffer joint with solder, but you also get a lighter joint that won't deflect as much and doesn't *need* to be as flexible. (and don't over crimp, you'll work harden the strands!)
This part is my opinion... Unless you have a good set of ratcheting crimpers, which most car folks don't know exist, the chances of a light or over crimp are a lot higher than anyone likes to admit. I can visually see a bad cold solder joint easier than I can see a bad crimp. Anecdotal, but I guess I am paranoid about my crimps and always second guess them... so, I have ratcheting and hydraulic crimpers for the various sizes.
Right place and a right time is really the point I guess. Neither is always right or always wrong and how you actually execute the method plays a big part.
I crimp my terminations... lugs, plugs, connectors.... I am not, by any means, suggesting that soldering is superior across the board.I'll still say that in a mid span splice or wire repair situation, I will go for a soldered lineman splice with an adhesive backed heat shrink over a standard automotive crimp. From a mass perspective, the butt crimp is heavier and you now need to secure the wire or risk it flopping around. Sure you get a stiffer joint with solder, but you also get a lighter joint that won't deflect as much and doesn't *need* to be as flexible. (and don't over crimp, you'll work harden the strands!)
This part is my opinion... Unless you have a good set of ratcheting crimpers, which most car folks don't know exist, the chances of a light or over crimp are a lot higher than anyone likes to admit. I can visually see a bad cold solder joint easier than I can see a bad crimp. Anecdotal, but I guess I am paranoid about my crimps and always second guess them... so, I have ratcheting and hydraulic crimpers for the various sizes.
Right place and a right time is really the point I guess. Neither is always right or always wrong and how you actually execute the method plays a big part.
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I can't say that I disagree with you on anything you said here. I used to redo crimps all the time after they failed a pull test, and I eventually did buy a ratcheting crimper. That was a lifesaver and definitely has made my wiring work faster, cheaper, and more reliable. By the time I threw out sections of wire and ruined a bunch of crimp connectors, I had paid for ratcheting crimpers 3-4x overI think we agree way more than you may think
I'll still say that in a mid span splice or wire repair situation, I will go for a soldered lineman splice with an adhesive backed heat shrink over a standard automotive crimp. From a mass perspective, the butt crimp is heavier and you now need to secure the wire or risk it flopping around. Sure you get a stiffer joint with solder, but you also get a lighter joint that won't deflect as much and doesn't *need* to be as flexible. (and don't over crimp, you'll word harden the strands!)
This part is my opinion... Unless you have a good set of ratcheting crimpers, which most car folks don't know exist, the chances of a light or over crimp are a lot higher than anyone likes to admit. I can visually see a bad cold solder joint easier than I can see a bad crimp. Anecdotal, but I guess I am paranoid about my crimps and always second guess them... so, I have ratcheting and hydraulic crimpers for the various sizes.
Right place and a right time is really the point I guess. Neither is always right or always wrong and how you actually execute the method plays a big part.
^^^ This
The crimp vs solder debate will go on forever, don't get bogged down in it, they both have their pros and cons. I worked for a wiring harness manufacturer for several years, 99% of connectors were crimped, only a few special applications were soldered. On my vehicles I use both depending on where it's located, how much vibration it will see, etc.
Definitely get ratcheting crimpers, I've used them for 20 years and it's the easiest way to get the best crimped connection.
The best thing you can do is learn to read wiring diagrams, the Toyota EWD has a section in the front that's worth reading and find whatever sources you can for "How to read Automotive wiring diagrams/schematics". Reading electronic schematics or schematics for your house are different, you need to specifically look for info sources specific to automotive.
Also when working with wiring diagrams, you best friend is a set of colored markers. Read the colors for each wire and then actually color the printed wiring diagram. This will take a little time but can prevent a lot of mistakes.
Fine point colored markers - Amazon link
I used silver sharpies for grey (these are paint pens so they work great on metal as well)
Sharpies - Silver, Gold, Bronze - Amazon link
For wires with a colored stripe (which is very common on vehicles), such as Grn/Ylw I alternate between green and yellow on the same wire about every half to one inch so I always know that wire has a stripe.
As you learn more and wire more, eventually you can make your own wiring diagrams, if you are doing custom work to your own vehicle, make notes and stick them in a safe place such as in the owner's manual or laminate them and put them near the custom / modified wiring.
This can save you a lot of time later, and possibly avoid a lot of frustration. If the previous owners of all our vehicles left us notes about the wiring, we'd all be much better off.
You are likely the next person to work with the wiring again, set your future self up for success.
