Curve Generation
To get a 'leg-up' on grinding, Jim used his drill press to generate the
initial curve for the mirror, with the radius of curvature accurate to
an inch or two. The drill press head is at a slight angle as can
be seen below. The mirror is on a rotating turntable. The tool
used to grind is actually just a piece of pipe. The pipe section
is turning at the slowest speed for the drill press.
The real work of grinding the glass is done by the grit that is kept
on the surface. You can see the grit being pumped onto the surface
in the picture below.
Next we built the grinding tool...