Darryl Young asked:
"Would the top have dropped 3 1/2 steps if I had glued it to the rim first?......or is there any consistancy to how much the frequency drops when glued to the rim (only one plate glued to rim)?"
It's impossible to say: you're trying to compare apples (free plates) to oranges (plates glued to something). Yes, the siffness and mass of the free plate, and how those are distributed, do determine the resonant pitches of the assembled structure to some extent, but the mass and stiffness of the other parts comes into play as well. It's just too complicated to sort out without some fairly heavy-duty computer programs.
It's my opinion, FWIW, that the exact pitches of things, at ANY stage, are less important than other things. In the 'free' plates I pay much more attention to the shapes of the modes than the frequencies, so long as the frequencies are not too weird. Once tyhe thingf is together (and ALL together) it's the relationships between the mode frequencies that seems to count for more, and those don't have to be exact. For example, getting the 'main top' and 'main back' modes close in pitch to each other tends to maximise the strength of the coupling between them. This lowers the pitch of the 'main air' mode, and makes the 'bass reflex couple' stronger. This is good up to a point, but if the modes are too close together in pitch it can give you real problems. I talk about getting the 'main back' mode a semitone higher than the 'main top', but that's just a guidline, and it caqn be a full third higher and still be helpful.
In the end, the most important thing for you is to figure out what you like. Unless you're trying for some particular thing to see how it works, don't get too worked up about it. Just take notes, keep good records, and try to figure out over the next few builds what works for you. It might be something totally different from what I like. There are lots of good ways to make guitars.
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