I finally got around to repairing (again) my headphones.  As I noted, after the cord snagged on a chair, the left and right channel wires broke from their contacts, though the ground was still attached.  I kept meaning to fix them, but then I got used to the earbuds that originally came with the iPod.  They were by no means as good as my real headphones, but they did the job, and I was lazy.  Yesterday, however, they inexplicably lost the right channel completely, and it quickly became time for the repair job.

The physics electrics lab wasn’t there to supply me this time, but my brother was, so I borrowed his soldering equipment.  The first step was to remove the solder from the last repair job from the contacts, since I was reattaching it to the same plug.  Instead of the copper wire that we had last time, he had a handy little pump thing.  You primed it by pressing down on a plunger, then touched the tip to the heated solder and pressed a button, thereby sucking the solder into the depths of the device.  (After a quick google, I’ve found that it’s called a “solder pump,” or the somewhat sillier “solder sucker,” and looks like this.  The wire we had before is a solder wick.)  Since we had no reason to use the solder wick, I can’t compare the two.  I can say, however, that the solder pump worked pretty well, removing the majority of the old solder.  It did leave a sort of solder sheen on the surfaces, but that wasn’t a problem.

Then came the same process as last time, with a few modifications.  First was how I dealt with the tension relief, the fibers around which the wires were wrapped.  Last time, my roommate unwrapped the wires, cut out the tension relief, and then twisted the wires back up.  I tried that at first, but I’m apparently not as skilled as he is, and I ended up with scraggly looking wires that weren’t working well.  I stripped some more of the plastic coating and started again, and this time didn’t bother to unwrap.  I just burned off the painted insulation with a match, which I think probably burned out some of the tension relief as well.  Undoubtedly, most of it remained, but it didn’t seem to be a problem.

Unfortunately, I did have to go through the “making sure the channels are right” procedure again, and once again, I had them wrong the first time.  This time, though I wrote down which way they go, so I can do it right if I need to do it again.  On my headphones, at least, the red wire goes to the longer contact, the green to the shorter.  It was also easier to switch them and get them back through the holes of the contacts because I had some very fine-tipped tweezers.  A helpful tool, those.

Finally, this soldering iron was a bit trickier.  The first one was adjustable by a dial, so it could be set however.  This one could be set as either low or high.  Low wasn’t working, so I flipped it to high, but that was still problematic.  heating the surface and touching the solder to that, as I was taught, wasn’t working, so I ultimately had to melt the solder onto the soldering iron and then spread it around on the surface that way.  It gave me a workable join, and the headphones sound perfect, but it did result in some large and unwieldy solder lumps.

All in all, I’m glad to have my headphones back, and I’ll look out for attacking chairs from now on.

My roommate did acquire a soldering iron. I had expected to have to go into the electrics lab with him and maybe, if I was lucky, be allowed to solder. But the lab instructor just handed over the soldering iron and the accompanying business to Bevan. He brought it back to the room, and after setting up a workstation of a slate tile to keep from burning the wooden floor, he proceeded to teach me to solder. We followed an excellent guide I found for changing a headphone plug. We differed from it on only a few points–the wiring in my headphones had tension relief material in it, which looked like tiny threads, so we had to separate that from the actual wires and cut it out before doing anything. Each “wire” (left channel, right channel, and ground) was actually made of a bunch of small wires wrapped around the tension relief, and each of the small copper wires had some sort of insulation painted onto it (except for the ground, which was uninsulated). Filing was working to get it off, but going very slowly, so we resorted to touching it to a flame, using pliers a little way down the wire as a heat sink, and that burned it off quite quickly. After that, it was a matter of getting tiny wires through small holes, soldering all of the connections, and screwing the pieces of the plug back together. I now have perfectly working headphones, and can proudly say that I fixed them myself (and with Bevan, of course, who had all the knowledge and did much of the work.)

Never having soldered before, the thing that surprised me was how quickly the actual soldering went. Touch the iron to the wires and heat them, touch down the solder, let it draw in, and then the connection is done. What did take a long time was setting everything up. The iron has to heat up, and the insulation has to be stripped, and the work station prepared, and proper lighting acquired, and a helper to hold the work (If you do not have, as we do not, a soldering stand), and every time you put the iron down for a while, you need to clean and tin it again. I suppose that like everything else, it’s all in the preparation.