BGA Hand Soldering Video

By 2016, most people have got the hang of doing SMD soldering in the garage–at least for standard packaging. Ball Grid Array or BGA, however, remains one of the more difficult packages to work with [Colin O’Flynn] has an excellent video (almost 30-minutes, including some parts that are sped up) that shows exactly how he does a board with BGA.

[Colin] uses some spare boards to lock the target board down to his bench and then uses a custom stencil and solder paste to prep the board. Once he has the solder paste on, he places the components using a homebrew air tweezer and some regular tweezers.

For reflow, [Colin] uses the common T-962A with the open source firmware. Two other modifications to the oven: a custom vent hood with a carbon filter and a Jolly Wrencher sticker for decoration (we heartily approve).

[Colin] uses a microscope to do some inspection of the board, although the BGA could have concealed faults that would be hard to spot. At the end of the video, he did find a short (but not on the BGA, luckily, so it could be reworked by hand). He also melted a header shroud that would require rework.

The detail in this video is like spending an hour in [Colin’s] shop getting a first-hand look at the process and if you haven’t done this before–or you just want to pick up some of his tips–there’s a lot of value to that. We’re beginning to get spoiled with all the work [Colin] puts in to share his skills and knowledge. He presented a fantastic USB workshop at the 2015 Hackaday SuperConference, and did an amazing job of designing and documenting high-end embedded hardware security equipment with the second place winner in the 2014 Hackaday Prize: ChipWhisperer.

We’ve seen custom BGA rework stations and even some crazy hand-soldering of small pin count BGAs. [Colin’s] method requires a stencil and a reflow oven (although a conscripted toaster oven would probably work).

31 thoughts on “BGA Hand Soldering Video

  1. Not sure what you would call hand soldering when it comes to BGA. I’ve had great luck soldering down LGAs by stencil pasting the pads, covering with generous amounts of flux (so the part ‘swims’ in it a bit), and heating up the PCB from the bottom of the board using a wide hot air nozzle. You can tell when you are there when the part shifts to center and has a bit of spring tension when attempting to nudge it. Same technique should work for 1mm and even .8mm BGAs. Though I have not tried yet.

    Hand tinning the board (or part in LGA case) doesn’t work well. The key for BGA or LGA is getting a perfectly consistent amount of solder on all pads. Which you can really only do with a stainless stencil. With a BGA you could, in theory, also skip the pasting of the board and just rely on the balls if you were sure to get good adhesion. Would need to be ENIG or better.

  2. Poor-mans method:
    1. Go over the PCB with a flux pen
    2. Go over BGA with a flux pen
    3. Put BGA on PCB and push around till you feel it fall into the soldermask holes
    4. Put a coin on the BGA to add some weight
    5. Stick this on a hotplate

    The hotplate is a chunk of aluminum with 1000W of cylindrical heating elements inserted into drilled holes, connected to an ebay PID controller.

    Success rate: 3 for 3 so far on an LBGA256 part, 1mm pitch. The first two had some opens, which luckily were non-critical. For the third one I put a coin on top (penny I think) and this lead to good success.

  3. At the HaD SuperConference last November, there was a German guy (forgotten his name) who gave a quick presentation on how easy soldering BGAs was. His main point was do not use any solder. All the solder you need is already on the BGA.

    His process was simply:
    – coat the area where you’re soldering the BGA with flux
    – Line up the BGA as best you can over the pads
    – Cook in your re-flow oven

    He points out the surface tension of the solder precisely aligns the package onto the pads. The solder balls on the BGA area perfectly tuned to attach the package; adding more solder is just inviting shorts.

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