I had a solder nipple come off my throttle cable whilst the hovercraft was in storage, and trying to put it back on is proving a pain in the ass. I've cleaned the cable, and trying to get any solder to stick to it is absolutely impossible. It's like the cable's solder resistant! It's old style solder, leaded type. I initially thought maybe the iron wasn't hot enough, so tried it on the gas bbq, which easily melted the solder. However the solder always just drips off the cable! It sticks jsut fine to the pliers I'm holding the end with! I managed to get them on before with great difficulty - and with one coming off I'm having doubts about the others. They can't fall anywhere bad, it's just annoying if you're racing and lose a carb / cylinder. Can anyone help? Or is there a solder free solution? This end goes into my throttle cable splitter - 1 to the throttle lever, then 2 carbs.
Might be worth getting some flux involved, if you haven't already. I always found, too, with stubborn wire that heating it for a few seconds (10-15) prior to trying to get solder onto it helped.
Sand the wire and the inside of the nipple and apply flux and try to resolder. You need a clean connection.
my god, I've sanded, degreased, burnt, etc. The cable has gone yellowy so i'm suspecting some sort of zinc coating perhaps...? I've pretty much run out of solder (it drops to the ground and is very difficult to re use) so I'm very tempted to weld the end of the cable into a blob. I'll be back in an hour saying i've melted all my cable ps thanks for moving the thread, I wasn't entirely sure where to put this!
try using different kinds of solder you know lead free or like maybe 60/40 with rosin core ,, maybe try something with an alloy
My first thought was that you had a stainless steel cable but galvanised could be right; both are buggers to solder. Some aggressive treatment is needed to shift the zinc at the point you need to solder and an aggressive acid flux in soldering, followed by a good rinse in hot water to get rid of any residue. It's not really a job for a soldering iron, a little blowlamp's maybe better.
Might also be worth pointing out the zinc fumes will be poisonous (to the point that even an idiot like me would be apprehensive) so take care.
It's funny there's almost no info on the subject through google. Anyway, suspicions are confirmed - it's definitely galvanised. I put the welder onto it's lowest setting and buzzed the end of the cable - if it's pointing downwards 1/5 welds forms a blob when it cools. Too long and it just drips off, too short and it doesn't melt enough! It's a small blob but it's enough; it won't exactly come off. The only problem is it's very difficult to get the exact length you want! I've had first hand experience of zinc fumes - they sting the nostrils, and it's a pain to get it off first. It's gotta be a metal joint as it's under a lot of vibration / flexing so JB weld / resin / etc don't seem to work so well. No doubt it'll eventually pull through and I'll hit a tree cos i can't turn or something stupid like that
I'm betting that the pliers are nickel plated too, hence why the solder sticks to the pliers. See if you can find some brazing flux, and braze/solder it with a torch. Or possibly silver solder.
Possible sollution: soldering acid ? I have, as you have, tried to solder a steel wire/cable without any luck. The solder just beads on the cable surface (both silver solder and "electronics" solder). Recently my father gave me a bottle of soldering acid, and he claims it's great for soldering stuff that doesn't want to get soldered.. like steel wire/cables. It contains hydrochloric acid and some metal.. could be zinc.. don't remember. Anyway, I could do some soldering tests tomorrow with the acid, and let you know how it works. I'll call my father and ask which metal it contained as well, so you can make your own (you just let the metal dissolve in the hydrochloric acid).
Lo and behold! The soldering acid worked! =D It was finally possible to solder the stainless steel wire. Method used: 1. Face shield on! (hot splashing acid + eyes = badness) 2. Heated the end of the wire with the soldering iron. 3. Dipped the heated end of the wire into the acid and let it sit for a while. 4. Reheated and applied tin solder. 5. Rinsed thoroughly with water and dishwashing liquid (the base in the dishwashing liquid should neutralize any remaining acid and stop it from further corroding the metal). The result wasn't absolutely perfect, a small area close to the end of the wire wouldn't accept any tin solder, but at least it was _possible_ to solder the wire. I'm not sure why that area didn't get soldered, it might have had some burned glue from the adhesive tape left on there or something, as I didn't bother cleaning it properly with acetone and alcohol before the heat + acid treatment. *shrugs* I think I'm going to do another wire soldering test tomorrow (or the day after that) and see if I can improve on the result. This time I'll clean the wire properly and use a butane burner as a heat source (faster and more thorough). Also I'm going to see if there's any advantage to giving the wire three heat+acid treatments instead of just one before soldering. Going to try silver solder as well. I forgot to call my father and ask about the metal ingredient, I'll try to remember to do it tomorrow.
I'm a little late, but how about: Drilling a hole in a brick with a masonry bit, fill the hole with molten tin, dip heated wire end into tin and let cool. ?
