Science can't explain soldering paste. Long video, fast forward..
Posted Feb 22, 2017, 11:40 PM UTC
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How is the heat applied? Oven? IR? Likely HOT AIR!
In a technique known as solder reflow, the board is preheated and the paste (which includes flux) is liquified. Once stable, more heat is directed to the pin to draw the hot liquified solder up the pin, soldering it uniformly and cleanly.
Decent hot air application demonstration (though you could use a fine soldering point to heat each pin separately using contact, it requires much more accuracy and technique):
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Dude! Thank you for that.
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Welcomes! Too much tea tonight plus just saw the wife off to work so I'm bored haha
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I bet those fillets look like garbage.
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Since when is 2 minutes a long video?
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When you have crippling levels of ADHD
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When you think science can't explain surface tension, watching a video for two minutes is hard.
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Absolutely horrible title, good video.
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TIL about soldering paste
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For some reason, I didn't know that Molex size existed. I think I need some.
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Science can explain it. Just because it looks like black magic doesn't mean it is. See u/edmanep's explanation, he sums it up well.
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That's not a long video
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How the fuck are you going to say fast forward but not give a timestamp to when?
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Yes it can
Quite correct!
Surface temperature affects surface tension of the (now) liquid solder, allowing path of least resistance to flowing, compared to the cooler surface in between the contacts:
http://en.wikipedia.org/wiki/Surface_tension#Influence_of_temperature
Moreover, the flux will clean the surface of the metal contact making for a natural "wetting" process where the solder will tend to cling to the metal quicker than the board, the liquified solder following the flux in the paste as it spreads on the metal.
https://en.m.wikipedia.org/wiki/Soldering
(Wikipedia articles are not necessarily academically dependable, but these two have reliable sources referenced and are too numerous to reference separately here)
See also Gibbs–Marangoni effect as well as thermo-capillary convection (or Bénard–Marangoni convection)
That's a lot of words to say "magic"
Maybe I'm just horrible at spelling?
Just wait boi. If that nanotube video is any indication, we'll be seeing some crazy shit in a decade.
Non-Mobile link: https://en.wikipedia.org/wiki/Soldering
^HelperBot ^v1.1 ^/r/HelperBot_ ^I ^am ^a ^bot. ^Please ^message ^/u/swim1929 ^with ^any ^feedback ^and/or ^hate. ^Counter: ^35319
Ah thank YOU, helper bot! So seldom use a desktop PC that I forget there's a difference sometimes. Almost rude of me haha... almost
If you think about it next time, you can just remove the m. from the link. Other than that, they'll always be the same.
Engineer here adding in my two cents, also helps that most solders tend to be eutectic which means that their melting point and solidifying point is the exact same temperature, this would mean that a solder alloy in a form of paste rapidly melts and solidifies at the right temperatures to be used in such an application. This combined with the surface tension the solder would have between the pins and the contact points explains why the solder seems to magically move.
Oh VERY nice! Thank you
Yo dawg, I heard u wanted yo shit explained so I explained yo shit and yo shit's explanation's explanation's dawg