Voice Coil Wire Soldering

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I opened up a failed tweeter and found that the voice coil wire had broken between the terminal and the coil, probably from fatigue, as I do not drive my speakers. This wire is ridiculously fragile, I broke the other side just by looking at it. Now the question is can this wire be re-joined? I do have an ok soldering station, the weller digital, is soldering worth trying and if so, what is the procedure and materials needed, tips? Thanks.
 
Welcome to the party pal..;)

I've repaired quite a few.

Failure modes:

1. Overdissipation...nothing to do, unless you have some small wire to replace the coil. It's fun to do if you have a microscope and some good high temp epoxy, but after doing it, don't recommend it.

2. Squashed wires: I repaired about a (seems like) thousand T-3500's (or T-350, I'm not sure which number the tweeter was). When the manu put them together, the cardboard insulating piece really squashed the daylights out of the wire from the terminal to the voice coil. I used a single strand of wire pulled from a zip cord or something like it to do the repair..back then, I could see the wire..:bawling:

3. Ultrasonic fatigue: When ya clip the amp, the tweet gets some hf energy, and most tweets don't support the vc wire within the entire gap, so where it's in the field but loose, it can resonate, fatigue, then fail. If you have a microscope, you may see the rough texture on the wire really close to the break.

If the wire is copper, it can certainly be repaired. I had a pair of Guass Cetec tweeters, major ones, that had aluminum edgewound wire...that I was unable to repair..

Cheers, John
 
Funny you mention this as I just did a peerless 2" dome last month (old Vandersteen 2A)

On mine, the termination at the corner (going away from the dome) broke. I had to peel about 1/4" off the dome to make enough room to resolder.

The coil wire is extremely fragile and what makes it hard to solder is the coating has to be scraped off.

Get yourself some reading glasses, about 250 power with alot of light and the smallest solder dia. with the lowest temp that will do the job.

If your successful, you must coat the area you soldered with some flexible glue (I used Spray 90- contact cement used with Formica counter tops) while using a small brush to coat this over.

Ive never done a tweeter and this might not work considering the smaller size and change in inductance but what the heck...

Regards
David
 
Here are some photos of the broken wire. The wire is coated. What I was planning on doing at this point is using some solder braid to solder each end of the wire onto, then securing with epoxy or hot melt. How does one get the varnish off the wire? This wire is extremely delicate. It's a $15 tweeter by the way, nothing lost if it doesn't work out.
 

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