New photos/text at:
<http://tech.groups.yahoo.com/group/sct-user/files/LX200-OTA-disassembly/>

This 12-inch LX-200 is fairly typical - about 0.003 inches gap
between the main mirror cell and baffle tube. I want to keep the
main mirror movable, but I also want to get rid of this slop. What
to do? Make a clamping collar. Yes, you can cut 3/8-inch aluminum
with a $10 hole saw. Clamp the work, use a slow speed, and lots of
cutting fluid...even WD40 will work.

The finished clamping collar has three set screws that squeeze the
mirror cell tube. You can adjust the amount of pressure applied, and
make the slop much much smaller. The mirror's rear retaining ring
has been modified to do the same so that both ends of the tube have
reduced slop. It also helps to modify the focuser to position it
much closer to the mirror's center. Note rough edge of casting at
very right edge of photo. This casting should have been rejected.

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Tom Krajci
Cloudcroft, New Mexico
http://picasaweb.google.com/tom.krajci

Center for Backyard Astrophysics (CBA)
http://cbastro.org/ CBA New Mexico

American Association of Variable Star
Observers (AAVSO): KTC http://www.aavso.org/
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