solder weld then crimp or crimp only

[oldboot]

Back to the whole solder is a bad conductor thing.......obvioulsy I have to present a complete argument.

This was a specific question asked.

Solder made of lead and tin is beyond argument "not a good conductor", it has about 10% the conductance of copper.... lead & tin are two of the worst metalic conductors we commonly use.

This is why in all soldered joints that depend on solder for electrical conductivity, there should be at least 10 times the cross sectional area of the cable or wire in the joint....... most people do not think about this because it is already done for them.....the jointing materials have this factor built in.

So a lug intended for soldering will have a barrel at least 3 and abit times longer than the diameter of the cable.

Here lies the rub.......crimp lugs are so common now that solder lugs are far from universaly available, particulaly in onesies & twosies.

SO it is quite common for people to take whatever lugs they can get and lacking a crimper, they solder them on.
If they are a lugs intended for crimping only the tube on the lug will be much shorter....length may be 1.5 to 2 times the cable diameter.

Thus if a joint dependent on solder and not intemate coper contact is used there will be a higher resistance in the lug due to the solder

Yess a hot spot can occur...possibly not if the cable is well chosen... but very possibly if the cable is run hard and close to its maximum capaity.

Solder does melt at low temperatures, its integrity is compromised well below its liquid point.

The liquid point of 60/40 solder is arround 190C, that is not even twice the boiling point of water.

So if you intend to solder a lug onto a cable particularly a large one in a high current application, you should make sure it is a solder type lug and it has a at least 3 and bit may be 4 times longer then the diameter of the copper cable.

.

Now to twosheds question.

to make a respectable solder joint, assuming you have the correct lug for the cable.

Strip the cable the correct amount, insert the cable in the lug and heat the lug which will heat the whole assemby, and add the solder......arround the edge of the collar and if there is a hole in the front in there.

if you want a good job you need to get the heat in quickly but dont heat too far and get the job done as quickly as possible.

tes the heat by dabbing the end of the solder on the job......once you have it all up to temp remove the flame and only reapply if the temp is dropping and the solder is not flowing.

hopefully you wont burn or melt the insulation

you should be using resin cored electrical / electronic solder..do not use acid.

once it has cooled if you are fussy you can scrub the resin off with metho & tooth brush.

allow any metho to dry off and apply your heat shrink.

tyring to fill the lug and then insert the wire is not the way I was taught and if the wire is a snug fit tinning both parts and sweating them together simply will not work.

cheers

[Bros]

to make a respectable solder joint, assuming you have the correct lug for the cable.

Strip the cable the correct amount, insert the cable in the lug and heat the lug which will heat the whole assemby, and add the solder......arround the edge of the collar and if there is a hole in the front in there.

if you want a good job you need to get the heat in quickly but dont heat too far and get the job done as quickly as possible.

tes the heat by dabbing the end of the solder on the job......once you have it all up to temp remove the flame and only reapply if the temp is dropping and the solder is not flowing.

hopefully you wont burn or melt the insulation

you should be using resin cored electrical / electronic solder..do not use acid.

once it has cooled if you are fussy you can scrub the resin off with metho & tooth brush.

allow any metho to dry off and apply your heat shrink.

tyring to fill the lug and then insert the wire is not the way I was taught and if the wire is a snug fit tinning both parts and sweating them together simply will not work.

cheers

My method. Heat the lug and fill to 3/4 with solder then add the stripped cable until it hits the bottom keeping the heat on the lug. If you have judged the solder right it should then fill up the lug completely if not remove the cable and add more solder then add the cable which will now be tinned.

Now here come the difficult bit, remove the heat while holding the cable perfectly still until the solder has set. If you have an offsider have them put a wet rag on one side of the lug to hasten the cooling reducing the possibility of moving the cable while the solder is setting.

[TheRealAndy]

Oldboot, your dribbling again.

Tell us what the actual resistance is of the solder in the scenario you are providing.

[finga]

We used to bind stuff that looked like bias cotton at the bottom of the lug where the cable came in to negate the need for stillness whist soldering.

The cable was freshly tinned and the lug was freshly tinned. Lug onto cable. binding done and then cable and lug heated and solder fed through the hole in the lug.
The cable/lug was was always vertical, or near vertical, with the cable at the bottom of the combination of lug/cable
The solder was held it by the cotton type stuff and the cable was still because there were no outside influences like offsiders DT's.
I did a lot at the top of poles so offsiders were a hindrance normally.
We used to get lugs made especially for crimping and also those especially made for soldering.
Easiest way to figure which was what was the crimp lugs had no hole at the termination end of the ferrule and the solder ones did.
They were all made specific to suit a certain cable

[Fed]

Bros has the right way to do it twosheds.
Anyone who has ever soldered a lug onto a battery cable will know that if you use a lug with the little hole in the end the solder will run straight out of the lug so it's important to use a lug with a blind hole in the barrel.
Also put the cable into the solder filled lug slowly & you will see the solder wick onto the cable when it's right. Keep slowly moving it in to the final depth watching the solder going right into the cable.
You will need to keep a little heat on the lug while you're putting the cable in because the cold cable will suck some heat out of the solder.
It's really very easy to do.
Keep a wet rag handy.
Once it's finished I smear a little silastic over the barrel and the cable then use heatshrink, you will see the heatshrink forcing the excess silastic out all round at each end ensuring a waterproof seal.
Holding the lug upright in a vise will make it very easy for you too.

[Fed]

Interesting Finga, I've always considered unholy lugs to be proper solder lugs.

[finga]

Sh!t. I missed a couple of pages.
Bloody hell. Look at what happens when you go off-line for a day.

I'm in Brisbane so I'm going down into the dungeon to look for some old crap like the Henley snot and the like.

Gees you must be an old-fart too Fed
Can you remember paper or lead insulated cables in homes and the pilot light for hotwater systems (boiler)??

[finga]

Interesting Finga, I've always considered unholy lugs to be proper solder lugs.

Your way would work well too. Main thing is to get the heat into the cable as well to make the solder wick and make sure the solder not to cool too quickly.

[Fed]

Twosheds, Finga's way of binding the bottom of the lug & feeding solder in through the little hole in the top if you have one sounds like an even easier way to do it. No chance of movement while the solder cools which is very important.
BTW, the oldboot method of laying the job on its side and feeding solder in from both ends will never work, the solder will just run out.

[finga]

I have never seen a soldered lug fail on its own accord but I've seen plenty of failed crimp lugs mainly due to people not twisting the wire before crimping, one bit of movement, the strands settle leaving an instant bad connection.

One for the old boys.... Henleys Compound. HaHaHaHa!
PS, do yas like my little ² thingy, I only came into this thread to use it.

The old loosening of the termination loosening because the lay of the cable becoming unlayed.

Gees now there's a work practise you don't see much now.
Twisting before termination...especially in things like circuit breakers and main switches and the like.
I bet you also wiggle the wire after tightening the screw and then retighten??

How did you do the little 2 gismo??
I had to do P=IxIxR before when I could have just done a little 2. Bugger

[Fed]

Hold the Alt key down & hit 253 on the number pad. ²

[finga]

BTW, the oldboot method of laying the job on its side and feeding solder in from both ends will never work, the solder will just run out.

Never work as long as the veranda known as my guts points to the ground when I walk.
Actually it's near the same reason too.
Gravity sucks.

[TheRealAndy]

The old loosening of the termination loosening because the lay of the cable becoming unlayed.

Gees now there's a work practise you don't see much now.
Twisting before termination...especially in things like circuit breakers and main switches and the like.
I bet you also wiggle the wire after tightening the screw and then retighten??

How did you do the little 2 gismo??
I had to do P=IxIxR before when I could have just done a little 2. Bugger

There ya go, I was always tought NOT to twist the wire, and that it should reamin exactly as the manufactured lay, especially when soldering. When terminating into a screw terminal, always had to use a bootlace ferrule, a practice which I still use today, even on trailer wiring.

[Fed]

The problem is that the manufactured lay gets sort of unlayed at stripping.
I think that's why people continually talk about the pull test on crimp lugs.

Has anyone noticed that people pull funny faces when they strip wires?

[Bros]

I'm in Brisbane so I'm going down into the dungeon to look for some old crap like the Henley snot and the like.

When you are there you might find some P & B tape.