Opinions on Wire Crimping vs Soldering vs Both

[Tidybuoy]

I'm in the process of wiring my Electromotive Engine Management sensors. I'm curious if anyone thinks I should be soldering the connections or is crimping sufficient? Or, should I be adding solder over the crimped connection?

Below is a photo of one of the connections. Most connectors are this type.

[Bill Verburg]

Originally Posted by Tidybuoy

I'm in the process of wiring my Electromotive Engine Management sensors. I'm curious if anyone thinks I should be soldering the connections or is crimping sufficient? Or, should I be adding solder over the crimped connection?

Below is a photo of one of the connections. Most connectors are this type.

solder and seal w/ shrink wrap if possible, also fully tinned wire is preferred

[Rawknees'Turbo]

Vern, I would not even think about soldering those type wires - crimping them the way you have done is perfect (in my opinion).

[timmy2]

You could touch a dab of solder to the crimped area if you don't think the crimp will hold.
Crimp a wire and see what it takes to pull it out.
A good crimper ensures a crimp is done properly, and will last a lifetime.
Your crimps look great.

['76 911S 3.0]

Crimp only, solder will make the wire brittle and fracture over time from heat and vibration. I would not flow solder onto any crimped connection, your crimps look spot on and I would not worry about them.

[winders]

Originally Posted by '76 911S 3.0

Crimp only, solder will make the wire brittle and fracture over time from heat and vibration. I would not flow solder onto any crimped connection, your crimps look spot on and I would not worry about them.

^^^ Word!

The only time I solder is when no other connection method will work.

[gwmac]

I spent many years installing car audio and I have never seen the stiff solder failure that is so often spoken of, If anyone has seen it please chime in. That being said those crimps look as good as the ones used through out a modern automobile. They will be fine.

[930cabman]

Solder is a metal to metal connection, not different from a weld. However some drawbacks can arise, copper can be work hardened by the heat required, plastic insulation can melt away somewhat.

My vote would be a solid crimp with the correct tool, it is possible a crimped connection could (maybe) have breakdown, but after 100 years who cares.

We restored a flood car a few years ago and did not find any of the crimped connections failed. 1985 Alfa spider was the specimen.

[Rawknees'Turbo]

Originally Posted by gwmac

I spent many years installing car audio and I have never seen the stiff solder failure that is so often spoken of, If anyone has seen it please chime in. That being said those crimps look as good as the ones used through out a modern automobile. They will be fine.

I've never seen solder induced problems with wire ends, like mentioned here and elsewhere, but I consider soldering ends like the OP is asking about to be a tedious and time consuming ordeal that offers zero benefit over properly done crimps (hence my "wouldn't even think about it" comment ).

[Bill Verburg]

guys, I have 30 years doing marine electrical systems, every joint is crimped then soldered then sealed, all the wire is fully tinned, if it's not the installation will not pass CG or Insurance inspection.

Do what you want, but solder is the industry standard where reliability is necessary

[jason2guy]

why would you solder that perfect crimp? have you ever seen solder on a factory
harness? its just not necessary, the wire isnt under a bunch of tension and that connector has strain relief built in

[timmy2]

Hopefully you aren't in a marine environment where Bill's methods are required for going out on the water...
Factory crimped the wires only, and they last 30-40 years. Should be adequate.

[brcorp]

OEM is crimped. Buy a good (expensive) crimper and shrink tube the connection.

[McLaren-TAG]

If you need solder then you didn't crimp it well. I understand Bill's point. On the other hand I installed thousands of mobile phones and couple hundred alarms back in the day and not once did a manufacturer demand soldering to gain certification as a certified installation shop.

The reason solder is called for in a high reliability environment is to compensate for a poor crimping job and every time you see a bad crimp it's because someone either used the wrong gauge connector for the wire or rushed the crimp or most commonly used a radioshack quality crimp tool.

If you've got the time and are not confident of your crimps, by all means, knock yourself out. Automobile manufacturers don't weld.

[Cajundaddy]

For a marine environment, solder and shrink tubing for sure. Salt gets into everything. I also prefer to solder audio electronics.

For automotive, a properly done crimp connector is golden. In 30 years of tech work I have seen only two crimps that made poor contact and caused problems.

[winders]

Also, soldering is quite error prone. If you don't know what you are doing (i.e., are not properly trained), you are much more likely to have a problem with a soldered connection that an crimped connection.

I know how to solder (i.e., have been trained on wiring and circuit boards) yet I much prefer to crimp only. Crimping works extremely well for automotive use AND just plain works better in high vibration environments for most people.

[winders]

If I were worried about corrosion, I would use dielectric grease and shrink wrap. You don't have to solder to prevent corrosion.

[wente]

Hey, I'm an life long electronics nerd... IMHO Crimping is as good as soldering when done correctly. I'm a huge fan of marine grade crimp connectors with the heat shrink casing for engine compartments. Alternatively, standard connectors can be used with a piece of marine heat shrink tube over the entire crimp. Just put the piece of tubing on the wire, crimp them like normal, give them a tug and make sure your crimp is good, then hold a heat gun to it, the tubing shrinks and seals the entire crimp. Marine grade heat shrink tubing has a glue that melts inside sealing the connection. The glue also provides additional strain relief since it glues itself around wire insulation. For small gauge wires I solder them and use marine heat shrink. So, just because the manufacturer didn't care, doesn't mean you shouldn't make it better Keeping air and water away from your crimps and solder joints will keep them from oxidizing, corroding, and weakening. Do what the Porsche gods would want you to do, and keep your connections solid, clean, and dry! It'll save you many headaches down the road!

[Quicksilver]

Here is a clue ...
The FAA will not certify any wire connections that are soldered. That should be a big clue right there. They do make sure that you have good quality crimp connectors by requiring that the parts are certified.

In other words: For the highest level of reliability don't use cheap crimp connectors and don't solder the connections.

[Willem Fick]

+1 for what wente, Quicksilver and others said!

In soldering there is a phenomenon known as a "dry joint", where the joint looks perfectly soldered, but the connectivity is actually impaired, and it is for this reason that crimping is often preferred where practical. Crimping guarantees connectivity, as long as you use a proper crimping tool correctly.

As much as touching a crimped joint with solder sounds like a good idea, you may find this impractical as some crimping lugs are made from aluminium. In addition, if you happen to use acid cored solder you may find that the solder actually ends up causing the crimped joint to deteriorate.

If you are worried about corrosion a far better option would be to use heat-shrink sleeving to cover up the crimp.