Don't worry, I'm still working on the series of articles I promised, oh, a year ago?
I've rewritten it several times, and it's 90% to the point of adding the illustrations to it.
I'll probably take photos of the various types as I build them out in the back yard, as I don't draw things "on the computer" very well, and I don't want to swipe random pix off the Web.
When this is finished, I'll post the sections of it, and if I can find a free place to upload a pdf for free access, I'll do that, too.
So hang in there, it's "In Work" as we used to say at Boeing!