Before I took this video, I carefully aligned the pins. Get the device as straight as possible (and orientated correctly!). It doesn't have to be absolutely perfect but it should be as close as you are able. At 0.5 mm pitch, this device is HUGE compared to the 0.4 mm PIC32MX parts I've been working with before. This makes aligning and holding in place while tacking pretty easy.
Honestly, the paste/reflow skillet method is faster and easier, but I wanted to follow the instructions as written by George N2APB.
This is good when you need to put parts on both sides of a board, anyway, and don't have a oven set up or a reflow heater/air gun setup to do two sided paste solder as I do not.
Then tack down a corner. Make sure the device is still perfectly straight. Then tack down another corner. I typically intentionally bridge 2-3 pins on both "kitty corner" sides of the device and clean up later.
This method is not as easy as paste/reflow but it is good enough when building one of something anyway as the results in the end are the same if it is done carefully.
Video follows:
Once the corners are tacked down.. do one row at a time. Flux liberally. Using as little solder as possible, "roll" a solder "ball"/"blob" down the pins with MINIMAL pressure. Be really careful not to bend any of the pins. It's a mess if one bends, trust me. Go back over the pins pulling the solder out from the case of the device outwards. Always do this as if there are bridges hidden near the case of the device it will draw it out. When you end up, like I did, with a couple of nasty solder bridges that can not be drawn away to the iron by flux alone, it is then time to use the wick (not shown in the video). Cut the wick off so there is a clean end (multiple times probably). Dip the solder wick into your flux (it helps). Using the clean wick end, draw the wick from the case of the device out. With wick, NEVER, pull across the pins or you will bend a pin, shorting it out and tacking it to the next pin over. BAD. Make sure that all of the bridge is pulled out by looking at the device under the magnifying glass. CLEAN THE FLUX OFF. This is NOT NOT NOT optional like George implied in the instructions. I don't disagree with him often but this time I really do. My own DSPic would have had two bridges concealed by flux if I had not cleaned it-- more than once. Probably if you had a big bridge you will need to re-wick it, re-flux it, re-clean and inspect it at least once more. When it looks like it does below, you are done. Repeat this for the other three sides.
* With the camera in the way, I inadvertently put too much solder on when tacking the corners down. It was also a little harder to do the work on the row of pins I did when recording the video. This was actually good as I put way more solder on that row than I normally would (and subsequently did not on the other three sides!).. but I ended the video with a couple of nasty solder bridges-- but then in the still pictures below.. you can see that with about a minute worth of fluxing and wicking the DSPic cleaned up really nicely. This proves that you can screw up a little and have no ill lasting effects.
Total time to place this was just under 10 minutes, including cleaning up the flux. Putting the camera in the way added about a minute and a half to the process. Nothing to fear when doing this.
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