This serious discussion could be fun.

Considering today's single ply designs and requirements for constructions
as, say, 4 mil dielectrics using, say, 2113 glass, there's not a lot of
"squeeze out" happening. The resin to glass ratio is moderate or about ideal
and when a specified press cycle is used, variations are minimal. Few folks
are going to high pressure, not that it matters, or are changing recommended
press cycles so few negative, or out of tolerance, changes should be
observed concerning impedance.

As you said, the press cycle is pretty much pre-determined for time, temp,
and pressure. Therefore, as little consequence is observable, there should
be very little change in the dielectric constant or the final impedance effects.

Foil thickness and, more importantly, edge raggedness, as a result of
operator process management ineffectiveness certainly is a major contributor
to wider changes in the final outcome. With all this, I don't believe the
press cycle to be a major factor unless it is greatly mis-managed. Getting
to 25 ohms impedance, depending on design requirements, is a trick unto itself.

MoonMan

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