Nuno Souto asks...
I'm having difficulty visualizing how this thing works.
Anyone has a link to a video of it in operation?
Thanks for the great post, Peter!
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Nuno,
I found the link to Roy's video.
www.pbs.org/woodwrightsshop/schedule/28season_video.html
go down to 
"A Very Boring Program"
and it is about at the halfway mark...

Regards,
Peter
In Melbourne, Australia

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