ATM 3" Surplus Shed Project Up-Date

[Joe Mayenschein <mayen1@mwt.net>]

Ok the mirror just left the test stand, and I was
quite surprised. As specified it is a f-10 sphere.
And a very nice one I might add. Both using  standard
foucault it greys evenly and completely with no trace
of   err. well anything.  And using the ronchi rulings
set all lines are perfectly straight and parallel in
all positions and number of lines.

I then removed it from the cell and measured the
thickness and it's 3/8ths thick so that's a 8 to 1
ratio in the thickness department..

So i guess it's thick enough. The way the mirror is
held in the cell is quite cheap but it works.  The
cell is made of a plastic pipe looks like black ABS It
it ever so slightly larger than the 3" mirror. This
extra slop is taken up by them wrapping the mirror is
several turns of a yellow paper. the ring that
surrounds the mirror is ever so slightly thicker than
the mirror. the same bolts that are the collimanation
bolts are also used to hold the mirror in place..
hhmm,, it's hard to describe,, I'll get the web page
made with some close-ups.

But optically the mirror looks excellent a better
sphere than I ever remember making he he he.

Joe
--
Ridgetop Stargazers
http://clubs.yahoo.com/clubs/ridgetopstargazers