It’s been a few days since I got the new boards but I finally got a chance to populate my boards. The solder paste I’m using is supposed to work for 6 months without refrigeration. It’s now been just over a year (ordered Feb. 11th of last year as it turns out), so I’m crossing my fingers and hoping it works:

As it turns out, it still works fine! And just because I didn’t document in my previous experiments with the paste, I’ll document it here. The spec for this paste says it melts at 183° C. So, I started the heat gun at 150° C for a couple of minutes to warm the board. Then every 30 seconds, I increased the temp by 10°. Once I hit 190, the solder melted quickly. I did have to go over some areas repeatedly to make sure everything got melted at once, but it all worked fine and the board looks like it worked well!

Unfortunately, now I have to deal with the switches, speaker, mic, and battery before I can test. Looks like it will be a few more days… So far so good though!

I got my prototype back from shapeways today!

The only bad thing I noticed here is that the holes I planned to put the wires through don’t go all the way through. There is a visible dent there (and a black dot on one where I tried to poke a pen through), but not an actual hole. Those holes are already way bigger than I needed for the wire, but clearly still too small for this material, even though it sounded like it would work. Well–that’s one of the reasons I did this quick test–just to see if everything worked as I expected. The walls actually seem thicker than I need, but I reserve final judgement until I wind one and see if it ends up breaking.

But, I’m out of town for a wedding this weekend, so I won’t get any more done on this until next week…