At 03:31 PM 1/20/2003, JaMi Smith wrote:
Respecting your having one larger Polygon Plane over several smaller ones, I
am assuming that you are speaking of the case where the smaller ones are of
a different net.

If this is the case, you would then be relying on Protel to not flood over
the smaller Polygon Planes simply be virtue of the net being different.
While this may in fact work, I myself would not rely on it, and would not
trust Protel to handle it properly in all cases, and would try to work
around the problem in a different manner.
The method is reliable. Remember, if Protel were to pour incorrectly, it would create error reports. Polygon pours are checked as if they were what they are: a pile of individual lines.

What I have been successful in doing in the past, and more importantly what
I feel comfortable and confident about doing, is simply this:
While it takes a little more work to do it this way, I never have to rely on
Protel to understand what I really want it to do, and there is no chance for
The method which Mr. Smith describes seems to me to be a *lot* more work. The previously given method I will repeat:

(1) place the inner pours and fill them.
(2) place the outer pour and fill it.

This method also prevents minor catastrophies which might happen if I
accidently deleted or renamed an inner Polygon Plane segment and then
"repoured" an outer Polygon Plane Segment.
The "catastrophe" is truly minor. If one is truly concerned about a pour being accidentally changed (remember, DRC will still detect shorts and opens), one can simply reduce the pour to primitives. (Tools/Convert/etc.).

In short,  you can draw larger Polygon Planes in smaller overlapping
segments, providing that they have the same net, and it is actually
preferable to have some overlap to prevent a "gap" in the gerbers, but it is
not advisable to overlap Polygon Planes which are not intended to be the
same net.
Well, it doesn't hurt for there to be an overlap, certainly, but if one is designing on-grid using consistent units such that round-off doesn't bite you, it isn't necessary. (i.e., if one uses, say, a 1 mil grid for primitive placements and uses imperial units for gerber generation and the line widths are in mils, no overlap is necessary, the films will fill completely with zero gap; in fact, we recommend setting grid to "0" for polygon pours, which informs the pour routines to place track at zero clearance.

Mr. Smith's method works, to be sure; and if it is simple to break up the outer pour, it could also be practical, but there is no more danger in using pour sequence to control nested pours, mistakes will stand out like a sore thumb. One caveat: if you move the planes involved, the automatic repour may not produce the desired results. But this is very likely to result in open circuits. If one will need to move a selection including nested pours, it might be a good idea to reduce the inner pours to free primitives first. Note that free primitives do *not* increase the database size since they are already there as part of the pours.

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