And now for something decidedly low-tech...

I'm pursuing the (painful) process of updating an older set of assembly
workmanship standards, as an internal inspection aid.

Per our specs, solder is not permitted to wick into the lead bend area,
for axial leaded components, mounted parallel to the board surface.
This stance agrees with  IPC-SM-780 (section 8.4.3.).  It does not, however, 

agree with A-610 (4.2.C).  Further, in J-STD-001, Table 11-1, item 17, it 
does
not state that solder in the stress relief bend is acceptable, but rather 
that
it "does not constitute elimination of stress relief".

I'm being asked to explain the reasoning behind my proposed change
(allowing  solder) and our older spec (not allowing solder), before it will 
be
accepted. This is, in essence, asking me to explain the seeming 
contradiction
outlined above.
I'm at a loss on this one.  Hope someone can help.

Is this one of those conditions that cannot be traced to actual failures in 
the field
(and is, therefore, no longer considered a reliability risk) or is there 
other
reasoning and/or testing which can be cited to illustrate that we were over-
cautious in the past?   I'm guessing the latter - how else can it be claimed 
that
filling the bend does not eliminate the relief created by the bend?

Any help will be appreciated.

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