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March 2004

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Subject:
From:
Steve Gregory <[log in to unmask]>
Reply To:
TechNet E-Mail Forum.
Date:
Wed, 3 Mar 2004 19:53:26 EST
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Hi Phil!

May I ask for you to tell me exactly what you have as "Tip Cutters"? This is
good information. We have manual lead trimmers here, but it seemed to me,
doing that was transmitting force down to the solder connection.

I observed fractured solder joints when I tried cutting the tie-bars off. As
a point, even when we separated the tie-bar cleanly without obvious damage, we
would re-reflow the joints to be sure that we that we healed any fractures
that might not be visible. This was done prior to temp cycling, because I was
still concerned about what it took to remove the tie bars.

This stuff is fun...ain't it Phil?

-Steve Gregory-
hi,

we hot bar soldered these connectors (b3) and used the tie bar to lift the
leads onto the lrm pad patterns.  after soldering, we cut them off with 'tip'
cutters.  our operators are outstanding and, to my knowledge, never damaged the
solder joints.  our first approach was to leave the non-conductive tie bar on.
 the first z-axis vibe test taught us that that was a bad idea.  we then used
the tie bar to flex the tails up and down to break it off.  again, a real bad
idea.  the cutters did the job for us.

phil

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