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I bought a cheap chinese infrared rework station, mainly to unsolder large QFN's or QFP's from a board. The main problem with hot air is the inability to heat large areas evenly.

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I can easily remove QFN's from a board with the station. Resoldering can be difficult because the board needs to be removed from the station to position the part.

A BGA already has solder balls to connect it back to the board, a QFN does not.

My question is, can IC's other than BGA's be resoldered to the board? What is the process that is used?

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  • \$\begingroup\$ Do you have paste stencil for the QFN part you're trying to resolder? \$\endgroup\$
    – brhans
    Oct 2 '19 at 15:31
  • \$\begingroup\$ Most of the time, yes \$\endgroup\$
    – Voltage Spike
    Oct 2 '19 at 15:53
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My procedure when I've occasionally done this in the past with QFNs & TQFPs is:
- gently but thoroughly clean the pads. - apply fresh paste
- place the new part with the help of a vacuum pickup and microscope (and sometimes start over because I smudged the paste everywhere)
- then carefully move the board back over to the IR station for reflow.
I'd usually apply IR from below and hot air from above at the same time, and generally end up successful.

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