Runny but fast-cure conductive epoxy?

At today's gold prices that solder would probably break the bank.

But anyhow, I found that "Bare Paint" from Radio Shack works nicely. It doesn't have much mechanical strength but that's ok in my case. And if it ever dries up on me I always know where to get more.

doubt radio shack won't be around much longer, last I heard was that they didn't even have enough money to close the stores

-Lasse

What happened? Did your customer demo come out OK?

Not yet. So far the DUTs I received failed but that's a whole 'nother problem :-(

The contacting worked great. From a silver wire strand of several mils to a 0.001" diameter gold wire I got 5-6 ohms per joint when the wires initially crossed while touching. That is plenty low for this application.

I doubt that. Many stores are franchises, not actually run by Radio Shack. The one I visited in El Dorado Hills looked quite healthy. Well, so far.

The two closest ones croaked years ago. The problem is that much of our youth no longer experiments or builds anything. And then there is the Internet competition from places such as Sparkfun.

I think lots people build stuff, sparkfun started in 2004 and now has something like 135 employees

it's just too easy when you can get all you need at half the price, instead of half you need at twice the price, by shopping online

-Lasse

They need to wake up and start selling things more relevant to today's builders and makers. Such as little uC boards and expansion modules that robot folks can use right out of the box.

Yeah, sure, but sometimes you need stuff now, as in this afternoon. Not tomorrow. Like when the brake on my mountain bike failed and so I bought pads for $15 from my bike dealer today. Considering that they cost as much as the big ones for my car but only last less than 1/100th of the miles I immediately followed up with an order for four more pairs for $12 total, about 1/5th the price. From China.

Radio Shack can survive this if they are smart. Sell things people need right away because something broke or because there is no time. That's how all the hardware stores survive nicely out here. If I have the time I order tools and installation materials online. But if it's Saturday morning and something goes *POOF* ... phssssss ... then I hop in the car or on my road bike and head to ACE Hardware. Which is kind of like a Radio Shack for plumbing and such.

I know, but just like you bike dealer isn't going to make a living selling a set of $15 brake pads, at least he can sell or fix a bike now and then

Radioshack would have to sell a lot of resistors etc. to make money

-Lasse

I doubt that temperature is the problem. I suspect that the gold is just dissolving in the solder. It also makes the solder behave badly which is why some people strip the gold plating off PCBs before soldering the parts on. They strip the gold off by putting solder on the pads then removing the gold-contaminated solder. This procedure isn't needed for ENIG boards because there is hardly any gold on there anyway.

Chris

Try contacting these people:

Most of their products require heat but maybe they have something that will do what you want.

Chris

Yeah, but ... when I lowered the temperature I could repeatedly solder this same gold wire without problems. It's just that the solder had a harder time melting and I also don't want to take a chance because all this stuff consist of one-off prototypes. The conductive "Bare Paint" from Radio Shack works well.

Thanks, Chris, but after contacting the local Radio Shack people I already got something that works. And to my amazement they had it in stock. People may diss Radio Shack all the time but there is something good that has to be said. These stores usually have enough nuts, bolts, boxes and stuff it takes to get to a prototype stage. Almost every time I walk in there I think "Oh, that's a pretty sparse selection here" but at the end I have a bag with stuff that suffices.