In my 4.25 inch f/4, I used double-sided foam tape to mount both
mirrors. That was about 1977, and they are still in place.
The primary is supported from the back, by short pieces of tape along
the outer edge.
The 1.5 inch secondary is attached to a wood rod 1 inch in diameter.
I covered the 45-degree face with the tape, and carefully positioned in
on the back of the secondary.
Star-collimation shows circular patterns, so I assume there is little
strain on the mirrors. At the 15 to 30 power that I use, it may not
matter.
Clear Skies!
-- Jim Van Nuland, San Jose (California) Astronomical Association <a href="http://www.svpal.org/~jvn/ ">JVN's web site</a>Received on Wed Mar 2 19:00:48 2005