3 ms·

I've found that surface mount is more bark than bite, to be honest. Boards that'll make it a pth device aren't terribly much, and I've done tons of surface moun

I've found that surface mount is more bark than bite, to be honest. Boards that'll make it a pth device aren't terribly much, and I've done tons of surface mount chips using the toaster oven technique. Even there, you can get a low end smd oven off ebay for not a terrible amount of money if/when you want to do any sort of volume work. Hell, with my crappy fine motor skills, I've nuked more stuff with the soldering iron than I have with smd, so things definitely have changed on that front.

tonyarkles 11y ago
There's two techniques that I find work very well for SMD ICs for hand assembled boards: - hot air rework wand. I got mine from China for $100. It works awesome both for removing parts and for melting paste. - flood & wick. You start by tacking down two corners of the chip, and then drag the tip with some solder along the full edge. You'll probably get some bridging between pins. Sometimes, when the moon is aligned just right, you just get a perfect solder. For the times when you don't, the next step is to take a bit of fresh wick and clean it up. Between these two tools (cheap Chinese reflow wand $100, and a nice Hakko iron $100), I've probably hand-assembled 75-100 prototypes and I don't recall ever destroying one. My next trick is going to be trying to do some BGA parts... new experiences!
- userbinator 11y ago
  Hot air is definitely the right way to do it for SMD/BGA, and I find it much easier than through-hole because you don't have to solder each pin separately -- just aim the gun at the part and wait for the solder to melt. The surface tension means the part will actually self-align into place over the pads if you get it close enough. BGA is not that much more difficult; look online for videos of the phone repair shops in China which can swap BGA chips in literally minutes.
cmrdporcupine 11y ago
Well maybe I should give it a try. We have the toaster oven set up in our 'maker space' at work, but I haven't tried it yet. There's a few people there well versed in it. There's a lot of things I would probably play with if I could do SMD.

tonyarkles 11y ago

There's two techniques that I find work very well for SMD ICs for hand assembled boards: - hot air rework wand. I got mine from China for $100. It works awesome both for removing parts and for melting paste. - flood & wick. You start by tacking down two corners of the chip, and then drag the tip with some solder along the full edge. You'll probably get some bridging between pins. Sometimes, when the moon is aligned just right, you just get a perfect solder. For the times when you don't, the next step is to take a bit of fresh wick and clean it up. Between these two tools (cheap Chinese reflow wand $100, and a nice Hakko iron $100), I've probably hand-assembled 75-100 prototypes and I don't recall ever destroying one. My next trick is going to be trying to do some BGA parts... new experiences!

userbinator 11y ago
Hot air is definitely the right way to do it for SMD/BGA, and I find it much easier than through-hole because you don't have to solder each pin separately -- just aim the gun at the part and wait for the solder to melt. The surface tension means the part will actually self-align into place over the pads if you get it close enough. BGA is not that much more difficult; look online for videos of the phone repair shops in China which can swap BGA chips in literally minutes.

cmrdporcupine 11y ago

Well maybe I should give it a try. We have the toaster oven set up in our 'maker space' at work, but I haven't tried it yet. There's a few people there well versed in it. There's a lot of things I would probably play with if I could do SMD.