Hello Steven,
I have come back from traveling to find some answers to my question that go far beyond anything I expected.
As it happens, I have discovered that there was a big misunderstanding between the company and me. I had always bought large canvases unassembled, but unbeknownst to me they had switched to selling them assembled with a $25 oversize package surcharge. I kept asking the salesperson how they could charge that for four segments of wood, and why couldn't they just box the pieces for the three frames together and imposes only one charge, and never did it dawn on her that she was talking about an assembled frame and I was talking about an unassembled one. Weeks later I thought to call back and ask, and discovered the mistake. They still let you make a special request that the segments be sent unassembled, and--can you believe?--when so sent, there is NO surcharge at all. So it went from $75 to $0.
I went ahead and bought the three frames, as this was the most efficient way to solve my immediate need. But that doesn't change my interest in putting together my own frames in the future.
I have to thank you for the weath of information you sent me and the time you took to write it all. I am going to save your email in a special file, because it will be basic to me when I get into it. It is helpful even in providing the terminology; now I don't have to talk about the "thingamagig" you use for this and that.
By the way, I see you live in Minnesota. To me as a East Coast resident, that is exotic and uncharted territory. But my son has been at the University of MN graduate school for a year now, and he has really enjoyed living there.
Again, thanks.
Sylvia Castellanos
http://www.sylviacastellanos.com