From: "Jerry B. Hillman" 
To: 
Reply-To: "Jerry B. Hillman" 


Hi all,
I'm back from Illinois. What beautiful country. Nice weather too. I decided
to work back towards a sphere in an attempt to correct the edge of this
mirror. I have done about an hour and a half of  COC 1/3 strokes, TOT. The
center 6" of the mirror is nearly spherical but the edge of the mirror
is showing little change.  After doing more research in the archives (on a
dialup connection no less) I decided that maybe I should switch to a TOT
'w' chordal stroke.  I'll try this tomorrow and see if I can progress in
the direction I want to.
For those who suggested MOT with a full sized pitch lap, thanks for the
input, but I am determined to do this TOT for several reasons. Primarily,
to avoid astigmatism. This is a THIN mirror. It needs constant, total
support. I can't provide that working MOT.
For those who wonder why I am still working on a mirror that had a good,
useable figure already.  Good, useable, isn't good enough. Is asking a F4.5
mirror to deliver sharp focus at 35 - 50x to much? That is my goal. So far,
this one won't do that, so I'll try again. I know the edge is a major
problem, so I'll fix that, and build a flotation cell. (Did anyone read
Nils e-mail about slings? Very interesting.) Clear skies, Jerry

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