i agree with John's view here

the supplied footprints are not all bad or entirely worthless but given
that you should check all footprints and put them in a
verified_footprints lib, the amount of work to make one is similar to
the amount of work to thoroughly check one

also there are widely varying standards and practices regarding hole
size and other issues

smd res paks come in a lot of sizes and shapes, the paste dots can be
very small, so the footprint design should be verified with your
assembler

i've had a bit of trouble with those being soldered properly, esp the
kind with the little cups at the edges, they are also hard to visually
inspect

between those issues single sourcing issues and routing issues i am
starting to shy away from them altogether after being a long time
advocate of the component count reduction they offer

Dennis Saputelli

John Haddy wrote:
> 
> I'm afraid you'll probably have to make the footprints.
> 
> As I'm sure I won't be the last to tell you: it's dicing with
> death (of the project) to use Protel supplied footprints. There
> are a large number of footprints in error to a greater or lesser
> degree. Every single footprint used should be carefully checked
> against the manufacturer's published component mechanical
> specification (there's also a wide variance in manufacturer to
> manufacturer dimensions for the same nominal package).
> 
> If ever I'm tempted to use a pre-existing Protel footprint I get
> up, go have a drink and remember what happened the last time I did
> so :-( , then go back to my desk and do the job properly (i.e. build
> a new footprint from scratch or by modifying one of my own
> previous creations.
> 
> Cheers,
> 
> John Haddy
> 

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