Start with a square piece of wood. Use a Forstner to hollow out the "hub" area. Using the center thus marked, cut the outside with a hole saw or fly cutter. Glue a dowel stub into the hole to produce the "hub." If you want the rim rounded over, maybe a roundover and router, but you could probably just as easily chuck a wheel in your drill press or lathe and round it with rasps/sandpaper/etc.
Or cheat and buy some ready-made wheels online. ;)
Or stains manufactured in Israel.
He tried. Can't find the diameter he needs in Canada.
djb
Can he buy them in inches and turn them down on a lathe that does metric diameters? Ed
Apparently not. 4-1/4" is what he needs and they don't seem to be readily available at that size or larger.
I think we've got a workable plan now, though... and I have an excuse to buy a couple of big forstner bits. ;-)
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