> in the oven at 450F to get the components off.  This works nicely, but
> combined with that and the recent post, curiousity begs the question of
> what is too hot?

Assemblies that need to work at high temperatures are not soldered, they
are spot welded (or impulse welded) using 'dead bug' technique on a grid
of leads held on a glass or ceramic frame. You can have circuits work
while they are heated cherry red in an oven ;-) There are valves (tubes
for others)  that will work when that hot. Look inside the base of a CRT
tube or HID mercury vapor lamp for ideas. The choice of parts that can be
used for this is very limited.

Peter

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