I have sort of worked out the headstock which should spin things as low as
60 rpm.
I am kind of stuck with the tooling side: the carriage, crosslide etc.
One of the questions I am struggling with is the size of the tooling
appropriate for this job (turning disks up to 9" in diameter). Instinctively
I feel that a 3/16 tool is not going to cut it (sorry about the pun). But am
I right?

I have a boxful of 3/16 and 1/4" tools, toolholders with carbide inserts,
toolposts and something which I take to be a crosslide of some sort into
which all these things fit. They all look rather puny. Would they do a job
of truing up the edge of a 9"x 1/4" disk? Would they face it? Or should I
design around something more beefy? If so, how much more beefy?

--
Michael Koblic,
Campbell River, BC