Help ! Is there really such a thing as conductive glue ?

[Nak Man]

I need to attach a thin wire to plate voice coil of tweeter, solder didn't work plus the voice coil is surrounded by fragile plastic. A quick google showed many results - but could anybody with experience with such glue please comment on its effectiveness, specifically for audio purposes ?

Thanks in advance.

 

[ooheadsoo]

Why didn't solder work?

 

[Nak Man]

They simply won't attach to the thin piece of metal (aluminum ? whatever) which very much looks like aluminium sheet wrap. The voice coil itself is flat just like ribbon tweeter. I'm sure I will damage them long before solder can stick to this metallic surface. One additional problem is that it's now as rare as hen's teeth so I can't afford to experiment much.

 

[Wodgy]

It's not entirely clear what you're describing. If the solder won't attach to the tabs where you would normally solder wires to the speaker, it's probably because your iron is not getting them hot enough. If you're trying to solder directly to the voice coil wires, you'll have to remove whatever lacquer or coating is on the wires first before the solder will work. Conductive glue won't solve this problem since the coating will still be there.

 

[Nak Man]

It's a technics leaf tweeter, so the 'voice coil' themselves is etched over a thin piece of plastic with nothing, no wire, to solder - except a larger area of metallic surface over which that thin wire was supposedly mounted and connect the ribbon to terminal. I wish I haven't stored them yet but I'll take pictures soon. It looks very much like a paper-thin pcb, but solder simply won't cling to the aluminium like metal (if only it was made of copper !). Solder tip was very hot and I was afraid to ruin the whole thing after first try failed. I've burned thick pcb using this solder gun before and don't want to repeat that on this more fragile piece.

 

[ooheadsoo]

Perhaps try a low wattage iron and take your time. Remove heat as soon as the solder melts. It shouldn't take much if the thing you're soldering to is thin and low mass.

 

[Nak Man]

Thanks ooheadsoo. I was thinking maybe this is one of those metal that is very difficult to solder (such as iron ?) - and prolonged heating may not be beneficial in this case. So I wonder if there's perhaps a safer solution to it. I would surely try your method if all other fails.

Btw have you ever tried one of those conductive glue ? They look interesting + promising but seems like they're not that easy to find in local stores.

 

[JaZZ]

I don't know about conductive glue. But you can't solder aluminum with normal solder paste! There's a possibility to get a reasonably tight solder joint with silver-solder though, if you're lucky. Otherwise there's special aluminum solder paste: http://www.solder-it.com/solderpaste.asp

 

[Nak Man]

Great, Jazz ! Thanks a lot !! I can't believe I even kept one over here. Need to find them now. Hopefully still works after years of storage.