[ATM] Cassegrain Baffles

[fundo at bellsouth.net (Daniel Fundo)]

<<  I am considering producing primary and secondary baffles for a 
Cassegran (D-K) telescope.  I have access to a lathe so in theory I 
could take a hunk of material and cut it down to make the baffles.  >>

Scott,  I have seen black Delrin tubing in several diameters.  There is
also plexiglas tubing available in extruded tubes in dozens of
diameters.

I also have a suggestion on the fiberglas/epoxy/polyester idea.  Find a
tube the right size for your baffle.  Wrap it with plain wax paper! 
Find an art supply store that sells black construction paper...the cheap
stuff that's like old style blotter paper.  Resins will soak into this
stuff like crazy.  Wrap the paper, resin, paper, resin.....until you
have enough to accommodate the machining, then a wrap or two of light
weight fiberglass, and another of the paper.  If you use epoxy, after it
sets up, place it in an oven for an hour at 140 degrees (if you can set
it that low) as a post cure.  It will come out as hard as a rock!  It
machines easily, but use a light touch.

If you can't find the construction paper, black felt will work also, but
it tends to be a bit messier and not quite a even, since the felt is
usually uneven in thickness.  Michael's and Hobby Lobby (craft stores)
carry the construction paper and felt.  Add std. disclaimer.

*****-----
Dan F.
Secretary/MAS
Memphis, TN