Wire joins: solder vs. butt connector

[AndrewBird]

I recently got one of these for uninsulated crimps:

http://order.waytekwire.com/productdetail2/M50/408/CRIMPING%20TOOL%20FOR%20WEATHERPACK/

Seems to work great, though I'm not sold on the ratcheting aspect of it. A bit hard to get used to. Makes a nice crimp though.

[BlackSpeed66]

Good thread! I'm by no means an electronics expert and there's some good stuff in here. For my own work I've always used non-insulated butt connectors - crimp first, then solder, then heat-shrink. Those plastic wire splice connectors are junk. I had to deal with the aftermath of those things on some of the cars I've owned where the PO used them. Ugh. Never been a fan of plain old butt connectors either as most of the time whoever used them did a terrible installation job. For me they've become synonymous with crappy wiring but this is why I find this thread interesting.

I've bookmarked that Grote company. I'd like to try out some of their stuff on my next project.

[freeride53]

Very good thread. Just went and bought a nice crimping tool.
Glad I didn't go ahead and solder my torn wires!

[bernzpeed]

Fedex overnight:

i have the channel locks. world of difference from what i've been using. so easy to use and plenty of leverage for small hands like mine.

[Gregs///M]

I have to disagree with many of the folks in this thread and I can explain why. I've been an electrical technologist for over 10 years now. I also work for a very prominent National Laboratory that builds custom electronics for next generation particle accelerators. I'm certified through an electrical industries association for rework modification, and repair of electrical assemblies.

It is very rare that we are allowed to use crimped connectors at all. And if in the event we are in a situation where we need to use a crimper, it must be a calibrated hydraulic crimper. Both the crimper section and strain relief must been calibrated by the crimper manufacturer. I've seen hundreds of times, wires are crimped too hard and failing over time. Of course we know what happens when they are under crimped. We cannot use hand strength crimpers.

Now soldering, I feel is the best technique aside from wire bonding. This requires a highly experienced technician in soldering like myself. One common mistake in soldering, which is not allowed at my work, is to strip a small length of wire, and coil another wire onto it. This is how failed and cold soldered joints are created and failed.

The proper technique is to cut the wire in half, then twist your cut wire and the new wire a minimum of 3 turns. Then twist with the other half of the broken wire. This will create a new properly soldered connection. Using this technique and proper techniques of soldering, cleaning, and protection of solder joints. I trust my solder joints to last many decades.

There are ways to prevent corrosion of your solder joints. At work, I often build cable harnesses that are exposed to Ultra High Vacuum and Ozone gas. IN these cases, the bare cables to be soldered are cleaned using 70% ETOH and the soldered using 35% lead/ silver with corrosion free flux. Once soldering has cooled, it is cleaned again, UHV safe epoxy if used to cover the joint and several layers of Polyolefin heatshrink is then used. This techinique is quote overkill for normal automotive used, except when exposed to weather elements like a trailer wiring.

I was a auto technician like a few dudes in this thread. I worked on thousands of cars throughout the years. I too have used crimp connector many times and prefer a nice Klein crimper. Crimpers surely make the job easier and with a good crimp, it will last a very long time. However, now that I am more experienced and on my own M3, I use my soldering technique and am comfortable knowing it will outlast any crimped connection.

Bottom line, for non experienced techs a crimp connection with a quality crimper would be ideal. For experienced electricians, soldering would outperform a crimped connection in both longevity, pull strength, current handling, and lower resistance.

I hope this clears things up a bit.

[Brian D]

I hope this clears things up a bit.

1 question, and an (old) observation. How much vibration are your wire joints subjected to? I'll betcha less than a car sees.

Airplanes still use crimped connections. I see more similarity between the operating environment of a plane and a car than a particle accelerator and a car (with the exception of Otis' monster).

Really, it is splitting hairs. IF you do a good job with either method, it'll last as long as 99% of these cars.

Oh, and Scotchlocks still suck. Sorry George.

[Gregs///M]

1 question, and an (old) observation. How much vibration are your wire joints subjected to? I'll betcha less than a car sees.

Airplanes still use crimped connections. I see more similarity between the operating environment of a plane and a car than a particle accelerator and a car (with the exception of Otis' monster).

Really, it is splitting hairs. IF you do a good job with either method, it'll last as long as 99% of these cars.

Oh, and Scotchlocks still suck. Sorry George.

It is true that most solder joints are not subject to extreme vibrations. But I would feel more comfortable knowing a well soldering connection would withstand vibrations more than a crimp connection.

You have to understand with a correctly soldered joint, the solder will flow throughout the connection becoming a solid joint, 100% continuity, close to zero resistance. With a crimped connection, a sharp metal blade is "pressed" into the conductors. On a microscopic level, this blade can bounce around and corrode from the difference in metal, which is less likely to occur in a properly soldered joint. Thus the crimped connector is more prone to a high electrical resistance.

Another matter why crimped connections are rejected is because the crimping of the wires create micro scores and breaks in the wire. And with time and vibration, can lead to internal wire strand failure. Think of it like this... Let's say you crimp a connection of a single wire of 20 strands of multi stranded wire. The crimp itself, "presses" against say 6 of those 20 strands. Over time and vibration, those 6 strands are scored at the point of the crimp and can become dislodged from the rest of the cable. Now your crimped connection is not as secure as it once was. This can lead to electrical arching, connection failure, and a higher resistance to electron flow.

With soldered joint, you would have none of these problems.

For most applications, either method is OK as long its quality is 100% OK. However, the best splice is no splice at all.

[German Audio Specialties]

And let me clear things up for you: not one automotive manufacturer solders ANYWHERE except circuit boards. ALL other connections are crimped. That should tell you something: in an automotive environment, solder is inferior.

Now, lets talk about my experience. I have been a high-end car stereo installer since 1980. I have installed car audio and other related electronics for a living since most members of this board's parents were in elementary school, and if you only have 10 years in a career, you may have not been out of 3rd grade when I started doing literally hundreds of connections every single day...in cars.

So, the facts are simple here: solder is a better connection, period. Proper crimping is far superior for many reasons though.

Solder is also absolutely pointless to use in an automotive environment...but if you want to, go ahead.

it ain't my car.

[Gregs///M]

And let me clear things up for you: not one automotive manufacturer solders ANYWHERE except circuit boards. ALL other connections are crimped. That should tell you something: in an automotive environment, solder is inferior.

Now, lets talk about my experience. I have been a high-end car stereo installer since 1980. I have installed car audio and other related electronics for a living since most members of this board's parents were in elementary school, and if you only have 10 years in a career, you may have not been out of 3rd grade when I started doing literally hundreds of connections every single day...in cars.

So, the facts are simple here: solder is a better connection, period.

It is also absolutely retarded to use in an automotive environment...but if you want to, go ahead.

Yes, Solder is a better connection, period. That is my point.

But I have to disagree with you in the automotive environment. What makes solder specifically "retarded" in an automotive environment?

Also, why do manufacturers crimp all their connections? The largest factor would be costs and human error factor. Both of which would indicate the primary reason manufacturers choose crimping. However, would you really trust a quality crimped connection over a quality soldered connection?

[German Audio Specialties]

Yes, Solder is a better connection, period. That is my point.

But I have to disagree with you in the automotive environment. What makes solder specifically "retarded" in an automotive environment?

Also, why do manufacturers crimp all their connections? The largest factor would be costs and human error factor. Both of which would indicate the primary reason manufacturers choose crimping. However, would you really trust a quality crimped connection over a quality soldered connection?

Here is the deal: as we all know, theoretical perfection is lovely and all, but generally it fails in real world usage and soldering in a car is much the same.

Yes, soldering CAN be a better connection (even though it has been proven higher resistance, but that is meaningless in this discussion) but it is still retarded. Here is why:

First, most automotive wire is crap. Sloppy, low quality insulation is the first sign, then very few strands, etc...automotive wire is crap. (BMW wire is the best I know of, so we have it easy there)

Thus, when it is soldered, even if top quality rosin-core is used, the flux "wicks" up inside the wire and corrodes it. That is why auto manufacturers use crimps. It isn't like Toyota couldn't do some form of robotic soldering, right? It isn't like those crimps were done by humans, it is all robotic.

The change was in the mid-70's BTW. All the brands used solder before that, but I think it was Ford who figured it out first.

Second, most people cannot solder 2 wires together to save their lives, much less do a tidy job. Yeah, a bunch of fruitloop tweaks that populate a forum like this have a lot better chance of pulling it off, but still, 80% of the people on here are not likely to make solid, quality connections every time either.

I am sure we can all agree that a crappy crimp is better than a crappy solder, especially in terms of current and voltage transfer.

Add to that the likelihood of vehicle damage from burns or dripped solder and the added hassle of repairing an incorrect connection...well, no thanks.

While we are talking about it, when is the last time you soldered together 2 30 year old wires? It has been about 2 weeks for me, thanks. Pain in the butt, huh? Good luck getting adequate flow or proper penetration on an ignition wire in the dash of a car. My crimped connections flow up to 30A or so for many many years without issue, and not just a few hundred, but literally thousands and thousands of cars.

That leads me to the next part of all this. I have said it before and I will say it again: show me any wire, any gauge, any type, anywhere in any car that has been soldered for more than 5 years. I promise you, if you cut that connection and strip back the first inch past that solder joint you WILL see corrosion.

Do the same on any crimp connection in that same car and the wire will be cleaner, every time. Think just for a minute how many soldered connections I have seen in 20+ years as a full time car stereo installer in a major shop in a major city...soldering isn't hard, and I can certainly give anyone alive a run for their money in a quality solder job...it isn't hard, but it is stupid in a car.

So, you solder guys, have at it. Me, the guy who was doing this stuff for a living long before most of you were breathing will tell you the same thing every time: soldering is retarded, don't use shitty crimpers, blah blah blah.

You can bust out all the calculators and slide rules and whatever testing device or NASA guidebook you want, I still have about 50000000X more experience connecting wires IN A CAR than all of those guys put together.

If you want a safe, quality, reliable, long lasting connection, buy a good set of crimpers (as stated earlier, I prefer the Channellock brand, but there are quite a few that are entirely adequate) and use the proper size connector. Crimp firmly, but don't try to squeeze the thing into oblivion, but hard enough for the metal tube to squeeze the wire strong enough to withstand a good yank...you will do just fine.

Make sense?

Luke

[homegrone30]

As I always understood both connections have there ups and downs dealimg with durability and corrosion. I always remember being told a soldered connection will carry more electrons (or is it protons?) because they flow on the surface of the metal. And when you crimp there is basically less surface area thus making a lesser connection. Im not saying your wrong Luke but how many alarms or stereo harnesses have you had to repair due to a shitty install using crimps. Vs an install with soldered connections. Does that question make sense?

[homegrone30]

And luke couldnt the corrosion have been there before your soldered? Im not argueing as this is all news to me. Ive always soldered everything because I was taught its better. Ive never had a solder fail but I have had several crimps fail.

[dwvw]

I crimp most things in a car, using Klein crimpers, very similar to the channel lock ones, but I like having one red handle and one black handle. Makes it much easier to line up the seam for the crimp.

Now for remote starters and alarms, everything is soldered and heatshrink is used, or solder and 3M tape.

[German Audio Specialties]

Lets be fair: lets compare quality crimp jobs that failed (proper tool, quality work) vs corroded-but-quality work solder joints. Since 99% of what a pro installer sees is crimped (lets toss the goddamn retards and their wire nuts, or the shitty "no tool" connectors, or stripped wire taped with duct tape, all complete trash in the trash, right?) I would say the crimp is fairly ahead, reliability-wise.

Generally though, those results are going to be skewed as good work rarely fails.

If you had any clue how many alarms I have taken apart, cut out all the solder joints and reconnected the same exact product and had it work perfectly when I was done you would never believe it.

Of course, all of that pales to the shittiest connector known: the "T-Tap". well. Of tools, shitty crimpers are easily the worst offender. Why the boneheads out there cannot seem to cough the $20 necessary to get a proper tool is beyond me, but I am the 10th son of a Bodyman, shop life is all I know.

As far as the whole "electrons flow on the surface" that is a well known concept, known as "skin effect". The actual point is that electrons spin down the surface of each individual strand...so if that were in fact the truth of how electrons travel down a wire, does it not seem to you that the "soldering" of a wire basically turns it into a single strand, thus massively limiting the actual current flow at the junction point?

Look, does this debate have to continue? Can we just say that a very well-known and respected 30 year professional installer says you need to get a good tool and crimp that shit? Nothing anyone has ever come up with is going to sway my opinion about solder and if you guys are as desperate to corrode some wire as you seem to be, have at it, just stay away from my electrical system. And, if you work on one of my customers cars, their warranty is void, period.

[homegrone30]

Not arguing like I said this is news to me, Im just picking your brain. But I do understand exactly what your saying and it does make sense. It just goes against pretty much everything I been taught thats why Im asking. I know you know what your doing Luke we should all know that by now.