Best wire splice method

[JimS]

What is your favorite wire splice method and why? I like soldering best. I feel they hold the strongest and do not corrode. I cover the splice with heat shrink. Using butt/crimp connectors and other types of crimp/quick connect splices I have had them corrode and sometime just come apart, particularly on equipment or trailers that are not used that often. In hot dry climates, the plastic eventually fails.

 

[Robin Hood]

solder, shrink tube, tape.

 

[Janicholson]

As you describe with a dollop of liquid tape on each end of the tube after shrinking. Jim

 

[Steve@Advance]

Depends on the application, but simple splicing in a harsh environment (wet, vibration), twist, solder, liquid tape, shrink tube, more liquid tape.

Same for attaching a terminal. I use the non insulated ones for critical connections, crimp, solder, shrink tube.

Lots of different splices depending on the application.

 

[MSD]

Twist and solder, then shrink tube.. I use shrink tube that has a glue in it that oozes out when tube shrinks.

 

[John T]

I would say crimp,,,,,,solder,,,,,,,,,,heat shrink,,,,,,,,,,liquid tape

John T

 

[Crazy Horse]

For those that have suggested tape at one stage of their procedure, I prefer what used to be called "friction tape" ..... a cloth based tape impregnated with a black sticky adhesive, tacky on both sides, stickier on the bottom though. I find the plastic electrical tape usually loosens and the ends dangle off, etc. Here is a link below ..... it is often used on the blades of hockey sticks, or something similar is used for that application. Today's friction tapes are not as sticky as they used to be.
Poke here for friction tape ....

 

[NC Wayne]

I've seen all kinds of splices fail.
Solder splices create a rigid area at the junction where the soldered strands meet the unsoldered strands that can break off from vibration.

Wire can fall out of butt splices if not crimped tight enough. The crimped area also creates a rigid break point, just as the solder does.

I don't like using wire nuts on anything except 'structure' wiring, but twisted and wire nutted connections tend to be the best I've seen.

Regardless of the splice, covering it with a quality covering, be it the wire nut, a cloth or rubber based electric tape (or both), or heat shrink if the conditions warrant, will go nearly as far at keeping the joint working properly as the joint type itself.

 

[Hobo,NC]

Crimp 95% of the time, using the right connector matched to wire size with the correct tool can not be beat...

If meting tin makes you feel good then melt away its just a feel good thing on most applications...

 

[john in la]

If we are talking a trailer;
I use crimp eye bolt connectors on tinned wire.
All connections are made inside water proof junction boxes.
Lights are water proof.
Ground wire is run to each light.
You can submerge the entire system in salt water with no problems.
Only problem is it ain't cheap.

I know some guys that run the same system but they use exterior extension cord wire rather than the tinned wire.

 

[Switchflicker]

I've found that the plastic tape ends stay in place better if you cut the tape rather than stretch and tear it.
Other than that I agree with the solder, liquid tape, heat shrink, etc

Stan

 

[Hobo,NC]

Crimp 95% of the time, using the right connector matched to wire size with the correct tool can not be beat...

If meting tin makes you feel good then melt away its just a feel good thing on most applications...

 

[FarmingEngineer]

I always use the open barrel splicing crimps. You lay all the wires parallel then crimp them shut. You need a high quality crimping tool though or they will not work right. Solder causes problems especially if there is lots of vibration. I usually cover them with marine heat shrink which has a heat activated adhesive that seals the connection. I've never had a splice like this fail on tractors, cars or motorcycles.

 

[37 chief]

I use what is the handiest at the time. Wire nuts seam to work fine for hooking two or more wires together, I try to leave the pointy end up to keep water out. Crimp on terminals. No salt out here on the west coast where I live to worry about. Someone mentioned friction tape. I also like that stuff. Stan

 

[DMartin9N-2N]

Good evening: I just happened to read this post, and BTW I did electrical maintenance work in a factory some years ago. I/we found the best plastic/vinyl tape for wiring was 3M's Scotch Super 33+ (or 35, possibly other numbers, it has been many years). Definitely cut it, not stretch it, to finish your splice job. Off brands don't hold up, 3M's Scotch 33 and its relatives will stay stuck!

Dennis M. in W. Tenn.

 

[Fred Werring]

Butt splices mostly.

Fill the butt connector with dielectric grease first if it's in the weather, insert wires, use a good crimper.
Will solder sometimes, but not often.

Fred

 

[Tony in SD]

If you want a good corrosion free splice it has to be water tight. The best product I’ve found to keep water out and have used for over 40 years is a mastic type tape. I’ve used it on connections on the top of towers and to repair underground cables buried directly in the ground. We currently use a 3M product linked below. Being trained in electronics prototyping, I choose to solder everything early in my career but I get as good of results using crimp connectors if done properly. I use a Klein crimper not the cheap ones that come with a connector kit. Then I put a layer of mastic over the splice. Sometimes I also coat it with liquid tape and/or Scotch 88 tape depending on the circumstances.
3M

 

[3000OH]

Solder, crimp, wire nut, busbar, I use ‘em all. Following the off-topic mention of waterproofing, I’ve had very good luck using hot melt glue to cover connections, especially odd-shaped and/or multi-wire. End result often isn’t good-looking but it is slightly flexible enough to help keep wires & connections from breaking.

 

[MarkB_MI]

I'm surprised nobody has mentioned environmental splices, which have been around for over thirty years. Raychem is one manufacturer; you crimp them like a regular butt splice, then use a heat gun to shrink the insulator. The Raychem splices have a bit of glue in each end that melts when heat is applied, sealing the ends. HD sells Tyco splices that are similar but don't have the glue. Although they're not as good as Raychem, the Tyco splices are still very good. And once you shrink them, environmental splices are much smaller than conventional butt splices.

<a href="https://www.amazon.com/Environmental-Splice-Ranges-Tin-Plated-Conductors/dp/B07B93F39Y">Raychem Environmental Splice</a>

<a href="https://www.homedepot.com/p/Tyco-Electronics-DuraSeal-Butt-Splices-16-14-8-Clam-Heat-Shrink-EB0314-000/202204345">Tyco Environmental Splice at HD

 

[INCase]

I"ll second that

we have something similar here at work. You push the strands of the ends of the 2 wires together. then slide the splice over that. then slowly heat it up with a hot air gun. the shrink parts will melt down on the wires and a bit more heat you can see the solder ring inside melt and move into the wire splice.

let it cool a bit and you have a water tight connection that you CANNOT pull apart.

very very good.

 

[Heartless]

depends on the application...

electronics - western union splice, solder (maybe) &amp; heatshrink

vehicles (including trailers) - western union splice &amp; often double heatshrink, outer layer being longer

soldering joints on anything that can produce vibrations will eventually cause the wire to break at the solder joint.

a properly executed western union splice wont do that, ever.

as a former long haul trucker, i have made repairs on many, many lights on many trailers using the above method, and never had those repairs fail.. other lights might fail, but not the ones I fixed.

 

[Rich'sToys]

What's a western union splice?

 

[Heartless]

(quoted from post at 08:13:27 10/19/20) What's a western union splice?

you probably use it without even knowing it.. I have used this method for years and had no idea it had a name...

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[MarkB_MI]

> we have something similar here at work. You push the strands of the ends of the 2 wires together. then slide the splice over that. then slowly heat it up with a hot air gun. the shrink parts will melt down on the wires and a bit more heat you can see the solder ring inside melt and move into the wire splice.

Yes, those are very good as well.
Raychem solder splice

 

[MARK ROBKE]

I may have overlooked it, but I don't think anyone mentioned butt connectors with heat shrink and solder made into them. I like them best-fast and simple. You get sealed and soldered by using a heat gun or a mini torch. I absolutely do not like electrical tape. I worked on semis and semi trailers for 40 years and saw many taped up connections holding water-taped up so good you would never believe water could penetrate, but, it did. I would rather butt connector crimp with nothing else first. Mark.

 

[Hobo,NC]

Once you get over the cost of a good heat shrink butt connector you will never go back to a standard insulated one...

 

[8NChris]

If I do crimp the bare wire gets dipped in the dielectric grease before going into the connector. Soldering on someone else's vehicle is a no brainer but sometimes my own trailer or ???? gets crimped wire. That way the comebacks stay a secret.