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January 1997

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From [log in to unmask] Tue Jan 21 12:
25:42 1997
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Robert Cronin Wrote:
>  We have discussed what would be a reasonable trace spacing from the 
> breakaway holes to prevent this occassional scrap from happening. The
> initial figure of 0.200 inch spacing was deemed way to much by the
> design community. Another suggestion of two times the board thickness
> (0.124 inches in this case) was proposed. 
> 
> 1) Has anyone else seen similiar damage of this sort during breakaway ?  
> 2) Is there anyone who has experience with a miminum trace spacing from
>    breakaway holes that works well ?
> 3) Is there an accepted standard or Rule of Thumb (such as two times the
>    board thickness) that anyone has used without incident in moderate  
>     volumes (200 plus a month)?
> 
> Thank You in advance for any comments.
> Bob Cronin
> Eastman Kodak
> 

I have designs that have the 0.036" hole edge 0.050" from traces.
To the best of my knowledge, this has not been a problem.  I wonder
if the boards are being twisted rather then snapped.  Do you have
a process description for the operators to follow regarding snapping
breakaways?  I can see where a twist would cause some problems.

John Laur

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