Well Chaps, thanks to the excellent advice I got here I have developed, after several iterations (or what I like to call "preparations"), a working prototype Use-a-Roo strop. Preparations "A" through "G" were not good, but this last one, Preparation "H", feels good, on the whole! (With many, many thanks to Dr Evil). :D
It (my work) is rough, very rough. But good enough for me atm. What I really need is a straight edge. I had to basically freehand the bits using some wood I had laying around. Tomorrow I will go out and buy a metal meter ruler.
But anyway, here it is. It is two pieces simply riveted together and a couple of welded D rings. The plan is to use this for a couple of weeks, and see how it holds up. I did 5 razors on it about 30 minutes ago and it went very well indeed. No stretch (I used the bit of the hide recommended in the web site posted above). And very tough, for a thin strop. It showed absolutely no signs of wanting to break or tear during the previous stropping tests. Plus it feels like it did a tremendous job stropping the edge.
Anyway, here are some pictures. I bought some kangaroo lace to use to tie it to things, and that's what you see dangling off the top D ring. First pic is the front. Second is the back (they are identical really, because I used two bits of leather).
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Attachment 19101
James.