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Old January 14th 06, 07:36 AM posted to rec.radio.amateur.homebrew
Mike Young
 
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Default SMT 40m + 20m qrp

"Tim Wescott" wrote in message
...
Do you just sit the board on the bottom of the pan, or do you space it up?
Can you do double-sided boards?


There's just the slightest curve on the bottom of the skillet so it sits on
its corners. I don't believe this is critical. Direct contact on the face
will probably work just as well.

Components on the top-side only. You'll need to use a different paste if you
need to reflow top and bottom, and definitely need tighter control on the
temperature for the second side. An uncontrolled skillet won't do for that.
Use a tin/silver paste for the first side. Its higher reflow temperature
will allow you to reflow tin/lead on the second side. You'll want to use
stand-offs in a properly controlled oven for that.

What else didn't I ask?


Hot air is an alternative. I use a Weller Portasol with hot air nozzle for
small rework. I hear of others replacing the rubber bulb on a Radio Shack
desoldering iron with an aquarium pump. It takes longer to build a board,
but might suit the pace of a homebrewer better.

I've seen the web sites showing how to do toaster-oven reflow -- have you
tried that?


I haven't tried using a toaster oven. The concepts remain the same, however.
There might be a difference between heating with IR elements and heating the
board more or less directly.