Solder seal butt connectors- used them?

I've never really trusted them because if the wires are slightly oxidised you might not get a good solder joint. With new fresh cable they are probably OK but difficult to properly inspect the joint. I prefer either crimp or solder joints with glued heatshrink for waterproofing.
 
I have used them, but am not really a fan. You need clean cable, not oxidised black, and occasionally (using a mini blowtorch lighter) I have burnt through the plastic outer before the solder joint was made properly. Maybe the set of 4 sizes I got from Amazon was a cheap and nasty set, and there are better ones. One problem is you need three hands, two to hold the wires and one for the mini blowtorch. Like any solder joint, movement just as the solder solidifies can give a poor joint.
 
Per jwilson, I manage to damage or burn through the insulation far too often to be entirely happy with them. That said, I add heatshrink tubing for extra insulation and I've developed the trick of heating up the outer ends first to grip the wires before heating the middle to join them. Less chance of a dryjoint than just twisting and soldering wires (in my shaky hands, anyway).
I dont like crimp joints - too much experience of them pulling apart and the danger of moisture getting in. Adhesive lined heatshrink is your friend there, though.
And if you come across blackened, corroded wire, just replace it. Cut back to good bright copper if you must, as I've done on light load wiring. But the moisture that causes corrosion is wicking its way slowly along the strands of wire. It significantly increases the resistance in the wire run, causing problems later in time that are hard to find unless its carrying a high load when the cable will heat up. Alarmingly in one wire on my own boat. And the joints will always be poor.
 
I have a box of them, they're useful occasionally. Burning the plastic is easily avoided by using a hot-air blower (either electric or gas-catalyst) instead of a naked flame.

(But the naked flame will work, with care, which makes them a useful emergency repair device needing no other tools but a handy cigarette-smoking crew member, or failing that the galley stove lighter ;) )

Pete
 
Yep

I use them all the time; van engine / fuel system & electrics, boat engine / fuel system & electrics as well as using them to repair machine tools. One thing i do to add a bit of security (depending on application) is add a length of heat shrink over the original soldered butt splice.
 
Holy thread revival here. But better than starting a new one.

Just to say I was sceptical of solderseal joints and have used mostly crimping and heatshrink on my re wire along with wago connectors.

However i have been practicing and used solderseal with a heat gun and heatshrink on top and been very impressed with the quality of the joint. Also it is very useful if you dont want to increase the size of the wires too much.
I'm sure there are downsides but i've used them in non critical areas such as water tank sender.
 
Good quality ones are actually used in aircraft looms to add earthing wires to cable shielding. I wouldn't rely on them for splicing 2 cables together though.

If you want something smaller than a standard insulated heat shrink crimp, you can use an open barrel splice with adhesive heatshrink over the top.
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Quite popular in car wiring looms & harnesses
 
I've used them on my landrover and on my model railway. . They work well if you clean the wires first.
I use a gas powered Soldering iron, with it's hot air blower nozzle set on minimum..
 
They're not a very good connector, that's for sure, as it's very difficult to avoid a dry joint using enough heat, but only 'just' enough, to not burn a hole in the heat shrink. I've only used one brand from Amazon, which came in a batch of 'loads of them', a lifetime's supply, so other brands may have higher quality.
But they are convenient, and I have used them when I'm joining stuff that's in an awkward place, and isn't subject to any stress through movement or significant A's.
That last sentence is a confession and not an endorsement.
 
They are crap.
This. Yes, I have used them, several brands, including 3M.

  • The solder is very low-temperature melt. It must melt before the plastic is overheated. If the wire warms up under load, it melts.
  • It is too easy to overheat the plastic.
  • Often as not, you get a cold joint. To make a good soldered joint, you heat the wire, and the wire then melts the solder. The wire is hot, the solder is next, and the insulation is the coolest part. In this case, you heat the plastic, which heats the solder, which sort of heats the wire. The wire is the coldest part, almost guaranteeing a good portion of unseen cold joints. It's bass ackwards.
"They are crap" is kind. Just throw them in the bin.
 
Tried them and decided it was too difficult to get a consistent result. Kept them for emergency repairs (only need the lighter for the stove or a smoker on board) but wouldn't use them in a re-wire of anything important.
I wouldn't use them for anything. If I'm connecting two wires, I want a connection that will work today, next year and in 10 years time. Chuck 'em out and get a box of heat shrink crimp connectors
 
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