Soldering should be done at the lowest temperature possible, while achieving
the desired result. Some folks think that it is OK to solder at 700 degrees
Fahrenheit. This is not good!!

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Case, Jeff
Sent: Friday, December 19, 1997 4:55 PM
To: [log in to unmask]
Subject: Re: [TN] hand soldering on wave soldered board


Sheila,
Its not always just an issue of too much heat, many times its an error
in
how the heat is applied. Often I see soldering irons resting on pads
when attempting to heat a large component rather than placed on the
component lead. (Always like to mention cause analysis)

The damage progression I have observed is as follows:
1) Slight lifting of outer pad edges
2) Pad appears to start floating, edges curl up
3) Discolor and bubbling of adhesive and board surface
4) Separation of the pad from the barrel
5) Burning of board around pad (dry, flaking residue)

When breaking of the board fibers occurs (white spots, delam), I have
always found there was a physical inducement : trying to force a lead
that is too large into the hole, pulling a clinched lead through the
hole.

Hope this helps
Jeff
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 ----------
From: Sheila Smith
To: [log in to unmask]
Subject: Re: [TN] hand soldering on wave soldered board