Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "The man, the legend, the idol." video.

  1.  @nerdstrangler4804  You use hot air to prevent warping the board. Different materials expand at different rates when you heat them and if you use powerful soldering iron with a cold board, the changes are higher that something gets damaged because of rapid thermal expansion. Heating with hot air prevents hard temperature gradients and reduces risk of damage due thermal expansion differences.
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  2. And it also works as heat spreader with the hot air station which prevents heating just a single point on the board.
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  3.  @barms9768  If you get some no-clean reflow flux it should be just fine over long periods of time without cleaning up.
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  4. The video with solder paste application robot for motherboards can be found here: https://youtu.be/cnAFTMaS5R0?t=185
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