Morning Ben!
It's: Cg/Pa
Where C = Component weight in grams; P = total pad area in square inches (g/in must be 30 for the component to hang on).
Steve
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Gumpert, Ben
Sent: Tuesday, April 22, 2008 6:37 AM
To: [log in to unmask]
Subject: [TN] Old Topic - Bottom Side Parts
Technetters,
I was searching the archive for the rule of thumb on bottom side parts hanging on during top-side reflow, and found Tom Gervascio's words of
wisdom:
If component weight versus the surface area of solder (if the ratio of the two is less than 30 the part will probably remain in place)
What units are these? I doubt PSI. Grams/cm^2 ?
Thanks,
Ben
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