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1996

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Subject:
From:
Jack Olson <[log in to unmask]>
Date:
Wed, 27 Mar 1996 07:16:59 -0800
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[log in to unmask] wrote:
>      Due to a "non-existent" clearance between a PWA and a shielded case,
>      we would like to have certain components with lead lengths that are
>      not long enough to protrude through to the secondary side of the
>      board.  Thus, there would be no fillet for a solder joint.

We had a similar situation, but in our case we specified that the leads be 
clipped (after soldering), and the fillet ground down to .030 mils. These 
boards were for airplanes and had to undergo shock, vibration, environmental 
testing etc. NO PROBLEMS. Of course, you said your clearance was 
"non-existent", can you spare 30 mils? And by "shielded case" do you mean 
conductive? You might have to apply some adhesive KAPTON over the pads after 
you grind them, but at least by grinding you have the most lead length, and 
strongest solderjoint possible, still much stronger than a SMT connection, 
right?  
					           Jack
p.s. I would like to hear what others recommend, though... anybody else?



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