Parts should not move and leads deform while in the box during
transportation. It seems that the parts because of the big size and weight
are not properly package and allowed to shift and bend the leads. Perhaps
packaging them in the proper container will eliminate the problem. The
proper container should barely touch the tip of lead toes but not the bottom
of the feet and the cover should put pressure on the ceramic body when
closed.
Regards,
Ramon
> -----Original Message-----
> From: Collins Graham [SMTP:[log in to unmask]]
> Sent: Friday, April 25, 2003 7:01 AM
> To: [log in to unmask]
> Subject: Re: [TN] Velcro straps for matrix trays?
>
> Hi Eric, Brad, Arthur
> Thanks for the replies.
>
> Eric - An interesting observation, I've just blindly assumed that the
> manufacturer of the components would supply them with an appropriate ESD
> safe velcro strap. A dangerous assumption perhaps. But how dangerous
> is it given that the tray is conductive, the bench is conductive, and
> the operator putting on or removing the straps is grounded?
>
> The problem I've got is that these QFPs are big, ceramic, and have
> leads that behave as if they are made of butter. They have to be
> received, inspected, tinned, inspected, and pick/placed - so a fair bit
> of handling and examination. Using elastic bands has been a disaster,
> although my abilities to tweak leads with ax X-Acto knife are improving
> as a result. Using Kapton tape to secure the trays together has not
> worked well either, it only takes marginal movement to allow the parts
> to shift. The only success I've had is using the big clamp type paper
> clips, one can fasten two trays together with a clip on each end and
> there is no movement. Not a really practical solution though.
>
> The velcro straps work wonderfully, but we only have a couple in house.
> Most of our matrix tray packed parts arrive ready to use, with heat
> sealed plastic bands holding them. These don't get opened until we are
> ready to use them.
>
> Thanks all, and have a good weekend.
>
> Oh, and Peter Duncan - I flipped a long time ago. This is not new
> news. Just trying to put a bit of humor into a forum that has gone a
> bit dry...
>
> - Graham Collins
> > A mundane question for such a highly technical body, but hopefully
>
> 1.8e
>
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