Intro: PCB Soldering Tip #2: Corners First
If you solder up a component with lots of pins into a PCB, then realize it's crooked, you'll have quite the time trying to correct your error. I learned the hard way, and I've since taught myself this simple trick. With your component inserted into the board in its place (see PCB Soldering Tip #1: Tape), solder 2 corners of the component first, then flip the board over to check that the component is seated correctly. If it isn't it's easy to reheat the solder joints you've made one at a time to adjust the component in the board. After another quick check, go ahead and solder up the rest of the pins!
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