On 04/02/2017 07:26 AM, David Griffith via cctech wrote:
That's why I put this in the context of PNP robots rather
than hand-soldering. My last run of P112 boards was 150
and I'm thinking of doing another 150 or maybe 200.
Phew, I sure wouldn't want to hand solder 150 - 200 boards!
Been there, done that, never want to do it again!
There are machines that can do reasonable lead pitch spacing
without vision, using mechanical alignment.
My Philips CSM84 does 0.65mm lead pitch TQFPs quite well.
One other detail is lead coplanarity. The leads from the
manufacturer are formed AFTER plating to all sit on a flat
surface. If the leads have varying solder thickness after
removal, or are bent out of the seating plane by handling,
that will also affect the ability to reflow solder them
reliably.
Jon
