SRM32F411CE Soldering UFQFPN48 0.5mm pitch.

Just a quick practice SMD soldering of a small fine pitch microcontroller.
The chip is 7mm x 7mm.
The process was
Cleaning the board with alcohol (not show)
Soaking the flux.
tinning the pads with fresh leaded solder.
Soaking in fresh flux
Roughly position the chip.
Apply 350*C Air from 3 inches away for 1 - 2 minutes.
Begin to get closer and closer until you see the flux start to activate.
You can start prodding the chip now to see if it's flowing.
When the solder is flowing under the chip it will literally float on the solder below, it will self align and can be pulled around and will resposition itself again.
In this case it went quite well and I probably should have lingered a little longer in the flow, but I figured it was done.
Total time under heat was about 3 minutes with about 30-40 seconds at reflow temps.
I'll update the info IF it tests as working.

[@1over137]

4:20 for the action

[@DPLS77]

1:33 couldn't you just have dabbed on some flux on top of the chip, heat it with an air gun, and allow the flux to melt letting the chip easily fall into place because of surface tension?

[@klazzera]

no flux😢

[@1over137]

It's not easy to see, but it was covered in flux. There is a small puddle of it under the board when it's lifted too.
I use a flux pen, it's like a marker. You "paint" the area in flux.
I agree though. I probably should have used more.
The chip did "spring" itself into place eventually.
I never did test the board though.

[@klazzera]

@@1over137 ah okay youre flux pen guy. never used one of these and can't really say anything about them.