In a message dated 10/4/99 7:57:18 PM Central Daylight Time, [log in to unmask]
writes:

> Guys,
>  We are currently using a EMI shield which is dual in nature i.e. perimeter
>  is connected like SMT and leads are soldered like PTH. This shield is being
>  hand placed onto the board before reflow where perimeter is getting
>  connected to the board while the leads are soldered when the board goes to
>  wave soldering process.
>
>  Our problem is that this part is getting tilted easily and to prevent that
I
>  am looking for some kind of solution- Does anyone has tried out the kinked
>  leads to provide snap fit so that it won't tilt during the reflow
operation.
>  Any other potential solution to stop the tilt besides some kind of weight.
>  Does anyone ordered die and formed the leads and resolved the tilt problem?
>
>  My part is 1.5" X 2.5" with .5" height. Leads are .5" apart.
>
>
>  re,
>  ken patel

Hi Ken!

I do two boards (one is called a up-converter, and the other is called a
down-converter) that obviously has that "Black-magic" RF stuff in a section
on it, and uses RF sheilds. We print paste over the thru-holes for the leads,
hand-place, and reflow...what other little PTH there is on the board we
hand-solder, no wave (it's just a couple of connectors). The sheild winds-up
in a box shape on the board. The one thing that I've observed with these
sheilds that I have, and maybe why I don't have a problem, is that the
retangular shape is basically one strip, but having being stamped-out and
bent into the rectangular shape, they are joined at the ends by a piece of
kapton tape to hold its square shape during reflow...I don't have
problem...maybe that'll help ya'...

-Steve Gregory-

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