I know it's a small pic, but above is the base with -very securely- attached 20" bicycle wheel. The pile of stuff in front of it includes the flyer I'm borrowing (thanks Nancy!!) and the mother of all to hold the flyer, some tools, a bag of sand, and other stuff I'm using to make the treadle/pedal system.
Above: aerial shot of the wheel-to-frame attachments.
Above: another view of the wheel-to-frame attachment site. The rectangle base (pictured below) and the frame pole is filled with sand up to the connection with the bike wheel. It makes for a much more stable structure that barley, nearly imperceptibly wobbles. Which is pretty good for a cobbled together bunch of pvc and miscellaneous hardware.
I'll probably finish it tomorrow! Woo!