> Ok, so I'm tired of hand grinding! Mel Bartles sent me some picts of his
> machine and I have read Alan Macintosh's articles on grinding machines.
> Along with other material I have read I conclude the following:
> 1) Table speed around 100 rpm (seems high to me)
> 2) Stroke speed is around 30-40 (seems reasonable)
> Do those values sound correct or what should they be?
The 100 RPM is OK on the table for roughing, but I think <10 is better for fine grinding and polishing. If you want to do hand figuring on the turntable then 1-4 is even better depending on the size of the mirror.
> I'm still not sure if machines can produce the classic W stroke.
> If they do, how is it acomplished? I'm getting ready to lay this puppie
> out and make it.
You need two driven spindles, one as the main stroker and a side arm at 90 degrees at about 1/4 the speed. I think the machines I used to use in mass production were like that. This configuration is otherwise known as the Zeiss type. If you want more blending action with only one eccentric you can connect a passive side arm somewhere behind the driving pin: the further back the more ovoid the stroke...
Mark