I recently purchased a 1988 Meade 2080 LX5 from craigslist. My reasoning was, "Scopes are out of stock all over and I either have or can learn the skills to get it going again." I got the tripod, wedge, 60mm finder (most of it), and the 2080. Missing were the OTA star diagonal, eyepiece(s), any sort of power supply/adapter and cords, and the tube and eyepiece for the 60mm finder. Also some hardware for the LX5.
I did, however, get some extras. I got soil, a lot of it, all over the outside and some inside the finder and the OTA. I got a small mud dauber's nest inside the finder. I got a few desiccated insects inside the OTA. I got a lot of moth wing sparklies inside the OTA, on the back of the corrector plate, generously covering the primary, and liberally sprinkled on the inside of the tube. I got a lot of corrosion on the tripod legs. Oh, and some cobwebs behind the mirror and inside of the baffle tube.
Pictures are (hopefully) attached, but not too many (yet).
Thanks to this site, I got the tripod leg corrosion cleaned up by a vigorous application of elbow grease and wadded up aluminum foil.
When I was inspecting the corrector plate, before cleaning it, I noticed that the secondary mirror assembly would spin freely inside its hole in the corrector plate. When I removed the corrector plate (noting orientation) one of its retaining screws was stripped. I unscrewed the secondary mounting assembly and set it aside. Using a 70% water, 30% isopropyl alcohol, 2 drops of dish soap mix I loosened most of the dirt from the corrector plate, rinsed, then let it soak for a few minutes in warm water, and set it aside to dry. After drying I made another indexing mark on the corrector and OTA. An irregular cloudiness that I'd noted before cleaning I determined to be the corrector plate coatings separating from the glass.
Questions Set 1:
1. Is the orientation of the secondary mirror assembly in the corrector plate important?
2. What, if anything, should I do about the coatings on the corrector plate?
3. Pics below, but secondary mirroring is 'spotting' and coming off of the secondary. Should I get it recoated? (pics below)
Using a lint-free cloth I dampened and scrubbed a bit on the inside of the OTA and finder to remove mud streaks. That cleaned up okay. I used various optical-type squeeze bulbs to blow the cobwebs out of the baffle and from behind the mirror.
Pre-cleaning inspection of the primary revealed 1, half-inch-ish scratch in the mirror near and tangent to the baffle. I cleaned the secondary using the same 70/30 mix as above and lots and lots of cotton wool, kleenex, and cotton pads. There were some oily deposits and some greasy deposits that have left a faint haze on the primary.
I put it all back together and took it out to collimate. I managed to get Jupiter with a low-power eyepiece and managed to get the de-focused donut roughly symmetrical from its start as tightly pinched on one side and wide on the other. However, when starting to collimate 1 of the three screws was fully tight and the other 2 pretty loose.
Today I tried focusing the scope with a 2-inch Celestron dielectric star diagonal and 25mm and 7mm eyepieces at the top of a wooden power pole about 1/2 mile away. The best focus I could get could be generously described as "soft" and ungenerously described as "poor."
Question Set 2:
4. How tight should the collimation screws be? Loose? All firmly tight?
5. How best to remove the "haze" left behind on the primary (haze pics below)?
6. Is 1/2 mile away sufficient to get a good, sharp focus with this scope and a 25mm eyepiece?
7. Is the current Meade Power Adapter, 12v 5A sufficient to run this scope?
8. Knowing that this is a Halley-era scope, should I stop with the spending already and be happy?
And, finally, if anybody spots anything that I should have asked but didn't, what is it?
P.S. I do plan to replace the capacitors in the LX5 and hand controller.
Pics below. The first is the before. The 2nd is the primary mirror haze. The 3rd is more primary mirror haze and you can see the spot on the secondary where the mirroring is gone.