In article pan.2005.10.27.13.40.24.12656
@crazysquirrel.removethisbit.com,
says...
On Thu, 27 Oct 2005 13:28:44 +0000, Cicero wrote:
Have you considered using an old Singer sewing machine foot treadle? You
can usually find old sewing machine stands quite cheaply which incorporate a
foot treadle. They usually drive the machine via a round leather belt. You
might be able to cannibalise or copy.

Cic.

Yeah, I have considered it but I'm not sure it would be up to the job. The
flywheel I am hoping to turn with it is 80cm in diameter made from three
(or more) sheets of ply.

Flywheel on a Singer treadle is only 30cm, there's not much room to
expand it width-wise and none at all to increase the diameter, but you
might be able to fix some lead or steel plate to the sides. You'd still
have the problem that it drives from the outer rim, so is good for speed
but not for torque.

There is also the problem of expense unless
someone has one going for free...

Often available on eBay for a few quid if you can find one local to you.