>>> Greg Scott [log in to unmask]> 09/17/01 11:33AM >>
I do not know of one for placement, your assembly house should have guidelines for the
breakaway tab itself.
Find the locations you can not place breakaway tabs first.
Like not under the connectors that over hang board edge,  if the board is not rectangle in
shape
I would keep away from profile edges that are not on the outer sides of board profile.

Normally you only need one routed tab per side of board, but only you and manufacturing can
evaluate the design and make those decisions.

Some times it just takes a prototype to really find what works.
You can always make a blank board (no circuitry)  but must be correct thickness
with your best attempt and panelization and routed tabs.  Then check for rigidity,
ask your assembly house their opinion.

hope this helped.
Greg scott
Cray Inc

Keach Sasamori wrote:

> >>> "bbarr" <[log in to unmask]> 09/17/01 08:31AM >>>
>
> Several weeks ago I posted a request for information on v-score panels. I
> received quite a bit of helpful information. Thanks to all who responded.
> Now, the proverbial 'fly in the ointment' has arrived. The design for the
> board will have several connectors overhanging the edge of the board, which
> is going to interfere with cutting through the score lines. I guess I am
> back to the routed and tab method of panel. My question is now this...to
> maintain a degree of rigidity sufficient to prevent sag in the reflow oven
> and through the wavesolder machine, is there a guideline for the number of
> or spacing of the tabs? To recap, the boards are 3.5" x 5.5", .063" thick,
> and I envision a 4-up panel. Nothing heavy on the board, just the usual
> surface mount suspects.
>
> Thanks.
>
> Bob
>
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