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Subject: Re: [Homebrew_PCBs] Soldering QFNs

From: DJ Delorie <dj@...>
Date: 2009-07-31

Adam Seychell <a_seychell@...> writes:
> Use glass cloth under the PCB to avoid local hot spots.

Some other ideas, depending on what you're trying to accomplish:

1. Aluminum plate distributes the heat pretty evenly.

2. Coins. Put a coin on the hotplate that's about the same size as
the chip (a dime for 0.5mm QFN-32), and only that part of the board
heats up.

I've used the coin trick to remove and re-install QFNs. I think part
of the trick is to put a few dots of solder paste near the chip so you
know when it gets to melting temperature.