Heatshrink Butt Connectors vs Other Options

[JWC86]

Not trying to hi-jack this thread but I’m very curious… when would a butt connector be advantageous over a properly soldered connection?

Or is it just a situation where you don’t want to solder for whatever reason, non so much that solder wouldn’t have been better?

 

[NYEngineer]

Back in 2000 or so I helped a friend build a Camaro that we Frankensteined bigger EFI into. We soldered every connection on that car. Took many hours and we were very careful to do it correctly. The car is still running today in that configuration.
Earlier this year, a friend of a friend called me and said he was told I was the guy to help him with an EFI installation. I saw the car and agreed to work on it. When I got started I said to the guy the worst part will be the soldering. He broke out a huge selection of the heat shrink butt connectors and said use these. I was skeptical but gave em a shot. I used my ratcheting crimper and this little hair dryer like heat gun he had. Made the job a lot quicker. The crimps seem solid and when I shrunk them the glue oozed out slightly so you can tell it’s a water and air tight seal. I’m impressed.

 

[willbur]

Back in 2000 or so I helped a friend build a Camaro that we Frankensteined bigger EFI into. We soldered every connection on that car. Took many hours and we were very careful to do it correctly. The car is still running today in that configuration.
Earlier this year, a friend of a friend called me and said he was told I was the guy to help him with an EFI installation. I saw the car and agreed to work on it. When I got started I said to the guy the worst part will be the soldering. He broke out a huge selection of the heat shrink butt connectors and said use these. I was skeptical but gave em a shot. I used my ratcheting crimper and this little hair dryer like heat gun he had. Made the job a lot quicker. The crimps seem solid and when I shrunk them the glue oozed out slightly so you can tell it’s a water and air tight seal. I’m impressed.

I once thought soldered connections are best. However, in talking to friends that run cars at the strip, it appears soldered cant take the severe vibrations under race conditions. They all use crimped connections.

 

[NYEngineer]

I once thought soldered connections are best. However, in talking to friends that run cars at the strip, it appears soldered cant take the severe vibrations under race conditions. They all use crimped connections.

I have since learned that as well.

 

[tcp71]

Military and NASA spec is a linesman splice. Who said you shouldn't solder? It'll hold up to automotive use...no matter how hard.

 

[willbur]

Military and NASA spec is a linesman splice. Who said you shouldn't solder? It'll hold up to automotive use...no matter how hard.

Your opinion. Never said you shouldn't solder. I can do at least 10 crimped connections in the time you can do your one, and it will be just as good. Those guys that race know what works. To each his own...

 

[RooflessVW]

Not trying to hi-jack this thread but I’m very curious… when would a butt connector be advantageous over a properly soldered connection?

Always.

I only solder connections that must be soldered by design. Certain types of cannon plug pins, for example. Repairs get butt splices.

 

[14Accent]

Soldering in automotive applications is borderline outdated. Almost all OEM's have approved the use of either heat shrink butt connectors or the crimp and cover with the glue coated heat shrink method. It makes repairs so much faster and easier. I have a full collection of sizes for both butt connectors an heat shrink in my tool box. They're invaluable.

The top use I have for them is when replacing headlight socket. The last 10 years or so, manufacturers have taken to using the absolute minimum gauge wiring terminated by some of the cheapest sockets on the planet to power the headlight bulbs (LED's and HID's excluded). These poor quality connections fry more often than when I forget my sunscreen on the lake. Heat shrink connections greatly reduce the repair time when I run into that issue.

 

[MattPersman]

In vw audi group we were told to crimp connect not solder

For FCA it’s all a non insulated crimp piece that is to be soldered then heat shrink.

Depending on the severity of the issue I use the crimp butt connectors that have the heat shrink outside or soldering. I prefer to replace harness ultimately. However sometimes it is too costly labor intensive or not available any longer.

If you have an out of towner that needs a 2-3 wires repaired you just gotta do what you gotta do to try to get them back on the road

 

[Kira]

Ha-ha. I just AGAIN replaced "el cheapo" headlight sockets. I swear the plastic used in sockets is thinner than the cheap trays used to sprout flowers in a nursery.

I slide correctly sized heat-shrink tubing to the wiring then use small, uninsulated butt connectors. Get everything into position and hit it with the heat gun. It's been OK for me as the headlight wires are protected inside the headlight assembly.

These crimps with sealer built in are news to me. Thanks for the info.
Can these be found around or am I looking only at bags of 100?

Shark Bites are to plumbing what these sealed crimps are to automotive electronics.

 

[MattPersman]

Ha-ha. I just AGAIN replaced "el cheapo" headlight sockets. I swear the plastic used in sockets is thinner than the cheap trays used to sprout flowers in a nursery.

I slide correctly sized heat-shrink tubing to the wiring then use small, uninsulated butt connectors. Get everything into position and hit it with the heat gun. It's been OK for me as the headlight wires are protected inside the headlight assembly.

These crimps with sealer built in are news to me. Thanks for the info.
Can these be found around or am I looking only at bags of 100?

Shark Bites are to plumbing what these sealed crimps are to automotive electronics.

Perhaps some auto parts stores sells small packs of them it’s plausible that hone depot or Lowe’s may have them too

 

[MattPersman]

Here Lowe’s expensive but small pack

https://www.lowes.com/pd/Utilitech-...vA3abyfgDfoi1D0NQtQaAtNhEALw_wcB&gclsrc=aw.ds

 

[wings&wheels]

Just use Posi-taps.

Just make sure to buy the water tight ones if there will be any moisture... I saw what was left of a non water tight one used in a wet environment and it wasn't pretty; corroded, heat damage from the increased resistance. Complete user error though, but I'd either pack with dielectric compound or use the watertight ones if I had and concerns.

That said, QUALITY heat shrink butt connectors are my go-to, using crimpers that don't damage the tube...and using the right amount of squeeze.

Aside from buying a quality crimper, I would look closely at the crimping points for sharp edges, burrs etc. Too many stories of quality issues with (formerly) good brands.

 

[Dave9]

For numerous reasons, I am being told that I need to stop using solder (and heatshrink) for automotive wiring repairs.

That information is incorrect. If you are decent at soldering, it is a superior connection method. Crimping is faster, and more consistent reproducible good result if someone is bad at soldering (yet has a good crimp tool) but that is the only real advantage.

 

[Dave9]

Soldering old wires can be problematic because the surfaces of the copper strands have oxidised and are difficult to clean up because it is stranded. Solder will not flow properly. I crimp them and trust that the high crimping forces will cut through the surface layer of copper oxide and contact gets made to the fresh copper underneath the surface layer.

Meh, not really. If you strip back insulation and it's still oxidized beyond soldering, your insulation is shot and the wire needs replaced.

If the wire is that oxidized, don't continue to use it, an exception being very large, low gauge wires that are difficult to solder due to the amount of heat needed, like battery cables or to starter/alternator.

There is no reasonable expectation that crimping removes enough copper oxide to result in a good connection, it may work passibly but nowhere near as good as replacing the wire or cleaning the oxide off which is accomplished with a more active flux. If the wire is viable at all to carry the current, a good flux will work to solder it.

 

[Dave9]

I once thought soldered connections are best. However, in talking to friends that run cars at the strip, it appears soldered cant take the severe vibrations under race conditions. They all use crimped connections.

That is only because they are using substandard wiring techniques. Solder is never supposed to be a substitute for a mechanical connection, nor is crimping. The wire should be mechanically fixed in place such that there is not any flexure at the solder OR crimp point. Fail to do that, and the crimp is going to fail too, maybe sooner, maybe later, depends on how bad the work was done, with more than one variable involved.

If you do that, when/where you can, solder is more reliable, but I wonder if it was just poor solder joints. The "idea" to solder, and the actuality of doing it right, can be two different things. If someone is better at crimping, which is a skill with a smaller learning curve, that's what they should do.

 

[Dave9]

Your opinion. Never said you shouldn't solder. I can do at least 10 crimped connections in the time you can do your one, and it will be just as good. Those guys that race know what works. To each his own...

Except it won't be just as good, and in fact you can't do at least 10 in the same amount of time, "maybe" 3:1 in an ideal scenario (more than that and we're back to an inferior connection), but breaking down total time to do a job, you're looking at several minutes to get tools and diagnose/find, or fabricate, then this difference of 3:1 is like 15 seconds versus 45 seconds, a small % of total job time unless you are doing a massive rewiring job with quite a few connections.

If you are doing a massive rewiring job, all the more reason to solder instead so you don't later have tons of crimps to double check if something isn't working right, because you can tell right away if a solder joint didn't do (coat/flow) well but a crimp with oxidized wire, crimps the same even if the connection is electrically poor with high resistance.

 

[wrcsixeight]

crimping vs soldering arguments....
I would think I would have heard every side multiple times by now, and not click, but I cannot help it.

Here's my opinion.
Both have their time and place.
Sometimes one or the other is the better call.
Both can be done correctly, or good enough, or horribly, and there is no shortage of those who have encountered either end and feel ridiculously strongly about their opinions formed from that encounter.

One thing most might not realize, is solder, on a scale of 1 to 100, copper being 100 in terms of conductivity, is only about 15.
So tinning two wires, placeing them side by side then soldering them together, is hardly a low resistance connection, but perhaps the current so low it does not matter.

If twisting two wires together end to end, and two wires side by side, and then soldering them together, is too difficult, I usually crimp.

I dislike insulated connectors, and have bought lots of uninsulated connectors and use 1 or more layers of unequal length adhesive lined heatshrink.
If the wires will vibrate or see potential stress at the end of the crimp, or solder joint, I make sure it cannot flex right there.

Proper crimping can be taken to ridiculous levels, that some might consider just adequate.
Some's 'good enough' would be laughed right out of the cockpit by those with higher standards.

Here's two good articles on the subject:

https://marinehowto.com/marine-wire-termination/

https://marinehowto.com/solder-and-poor-trouble-shooting/

 

[Dennywires]

Both are equally as good when properly done. Depending on the situation I have used both methods without failure.

 

[diyjake]

Back in 2000 or so I helped a friend build a Camaro that we Frankensteined bigger EFI into. We soldered every connection on that car. Took many hours and we were very careful to do it correctly. The car is still running today in that configuration.
Earlier this year, a friend of a friend called me and said he was told I was the guy to help him with an EFI installation. I saw the car and agreed to work on it. When I got started I said to the guy the worst part will be the soldering. He broke out a huge selection of the heat shrink butt connectors and said use these. I was skeptical but gave em a shot. I used my ratcheting crimper and this little hair dryer like heat gun he had. Made the job a lot quicker. The crimps seem solid and when I shrunk them the glue oozed out slightly so you can tell it’s a water and air tight seal. I’m impressed.

What ratcheting crimper did you use?