I just finished a restoring to use a 10" equatorially mounted Mead telescope from 1992 for the Astronomy classes at Austin High School. The Mead Starfinder scope is a monster and I can barely move it by myself. Thanks to a cheaply designed secondary mirror spider, the secondary mirror had crashed into the primary. The primary survived with some dings and the secondary lost about a half inch broken off. A new spider, secondary, and primary mirror would cost nearly what a much more useable 8" Dobsonian mount scope would cost. I decided to make the scope useable again with the existing parts.

The mirror was filthy but a gentle bath in water and eventually some cotton balls and dish soap, followed by a distilled water rinse cleaned it up nicely. I dabbed flat black paint on the worst of the dings in the mirror to minimize light flares.

I repaired the broken spider with epoxy, but then realized that the cheap pot metal part had been designed to be clamped to the blades in place in the scope. I bet Meade saved a whole two bits on that. This meant that I couldn't install the assembled spider without breaking it again. Plan B was to tap and drill a piece of aluminum and use 1/4 x 20 threaded rod for the spider. I used some black heat shrink tubing to eliminate any light flare from the parts visible to the primary.

I aligned and laser collimated the mirrors without any issues. Reversing the counterweight so that the heavy end was outboard, just barely got me a good balance and the AC powered tracking motor ran smoothly.

I was lazy and didn't disassemble it to move it the 20 feet outside and felt like an ant carrying a piece of lead shot. A quick look at the moon showed a nice sharp image with amazingly little effect from the chunk of the secondary mirror that was missing. It goes back to Austin High tomorrow!