Thanks, Mike. That got it for me.
Actually I'd seen that before and it was very helpful. In that article you also wrote "Let's face it, no matter how small the gap is, it still needs to be sealed." Hmmmmm! Am I misunderstanding that statement??

I've also watched carefully where you demonstrated the process in your Get Airborne videos and I think I've got it. I did a practice hinge on scrap wood and it worked just as you describe.

thanks again

Frank