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How to best splice wires together?

I have a 4x8 trailer. It is parked in my backyard when it is not used. One of my dogs, stupid dogs, chewed the 4 way plug off the trailer…I cannot connect it to my car now. I found the other end. I am wondering what best way is to reconnect the wires again? Use wire nuts? Or what other things can I do to reconnect the wires? The 4 way plug is still intact. Thanks for all your help!!

One way to make the repair is to use some crimp type butt splices. The blue colored ones will most likely handle the wire size you have unless you have 12 gauge wire or larger. In that case you will need the yellow colored ones. Crimp the striped ends of the wires to the butt splice using a crimp tool and then wrap electrical tape over the connection to keep water out of the splice. After taping over each connection you may want to tape over all of the splices into one bundle.

Crimping will work well, as Cougar suggested, but if you really want the splice to be waterproof and permanent, solder the wires, then put heat-shrink tubing over the splice. (remember to put the heat-shrink tube over the wire before soldering, then move it into place, otherwise you’ll be left holding it and swearing)

There are sprays that keep animals away from things–they contain mixtures of various herbs and plants that animals do not like. I’d spray some of this on the wiring harness when you fix it, then the dog probably won’t chew it again.

That’s the way I would do it.

Soldering is the best way, which is what you asked for. Oblivion is also correct about the waterproofing - trailer wiring is notorious for corroding. Another way to waterproof is to buy a can of liquid wire insulation - the brush is part of the can lid. It dries fast, seals well, can be put on in multiple layers, and one can goes a long way. No need to have a heat source to shrink the stuff. Having four different trailers for boats and a utility trailer, I learned my lessons from the pain of experience. I also use dielectric grease on all the bulb bases to minimize corrosion there.

The worst thing you could do is to use butt connectors, water will get into it,cause corrosion and then you will end up doing it again.

Solder and shrink tube, that’s the proper way to do it.

I prefer soldering with the heat shrink. If you don’t know how to do it, it is a worthwhile skill to pick up.

That said, you can use the butt connectors, but as noted the key is the environmental seal. If I were going with butt connectors I would get the kind where the housing is heat shrink (rather than just plastic) and I would also use a regular piece of heat shrink over the top of the whole thing - redundancy is good.

Twist n tape is the quick n dirty way
Butt Connectors (red) are only SLIGHTLY better…i used to fill mine w silicon

Solder the connections and heat shrink if you want to put this to bed FOREVER…

or at least till the stupid dog comes back…The 2 first methods will corrode and screw up in time…without question

Except that they sell butt splice connectors that solder and hermetically seal, using a heat gun, in one operation. These have been around for a few years now. Shrink tubing is no guarantee against moisture ingress…

Solder and heat shrink makes the repair permanent unless the dog comes back for more. Anything else from butt connnectors to the fabled Two Wire Twist is questionable over the long haul.

Not your father’s butt connector- Just one example.

Heat shrink is not waterproof. For a trailer, these are superior to solder and heat shrink. Crimp to hold, heat to seal and solder the connection.

Me likey…seen those before. However Solder IS permanent…the wires encased in the molten solder are as clean as the day you melted it…it has worked for decades at a stretch for the last hundred years…

The solder joint is a fatigue point,sure it makes a good connection,until it breaks.

I use solder and electrical tape. If I feel lazy that day, wirenuts work for a while but plan on a little corrosion in a couple of years when you can then easily redo it with new wirenuts. Wirenuts filled with silicone rubber will not corrode nearly as fast.

PLEASE No one try to tell me that soldering wires together permanently is a bad thing. Just dont go there… Its too silly to argue about.

I’ve never had a soldered joint come apart even on motorcycles where much of the wiring is exposed to the elements and which also sees an abnormal amount of vibration.

Not even the FAA? sure a car is not an airplane and the same level of risk is not present but the fact that the solder joint presents itself as a point for the wire to break with fatigue is still fact.We were asked to present the best way and the best way is with the enviromentaly sealed butt connectors.

But is that really true? You’re encasing copper wire in solder, which also wicks into the stranded connection, at least if you heat it properly. You’ve also (hopefully) twisted the wires to make a decent mechanical and electrical connection before you even solder. It’s not like you’re REPLACING the metal of the wires with solder, you’re adding material, and also some thickness. If you bend the solder joint enough, the solder may crack and somewhat degrade the connection, but you still have the original copper wire underneath as well.

I’d suspect that unless the connection gets a truly unusual amount of flexing, that the soldered joint is easily as strong as the original wire, perhaps even stronger, assuming the soldering is done right, similar to a properly glued or welded joint being stronger than the surrounding material.

You also can’t make me believe that a cheesy butt-splice is going to have near the mechanical strength of a properly soldered joint.

Has anybody seen the paddle for the dead horse?

Are you declaring a win and leaving the room? Cougar you have 100% percent stayed out of the personal attacks on me and I do appreciate that. You are a better man for going after what I represent to be technical truths than attacking me personaly. The personal attack does not make the attackers case stronger, in fact it weakens it, people are not so dumb,we all learned about ad-hominem attacks in college or even high school, not the way to present you viewpoint. Feel free to attack what I say,I encourage it, but I ask that you stay out of the personal attack arena.

has greater stiffness and even poorer fatigue endurance than
copper; I simply browsed a few google hits on soldered wire fatigue, this little comment was from a site selling strain gagues.