Cleaning and Modifying the C11 Beast
By Joseph Guzmßn
This article is part 9 in the How-To series “C11 Cleaning & Modification”:
- Part 1: Removing the Corrector Plate
- Part 2: Installing a Rail Carry Handle
- Part 3: Removing the Primary Mirror
- Part 4: Flocking the Interior
- Part 5: More Grab and control handles
- Part 6: Installing side control rails
- Part 7: Cleaning the optical surfaces - Primary Mirror
- Part 8: Cleaning the Corrector Plate
- Part 9: Installing the Corrector Plate and Closing the Tube
Part 9: Installing the Corrector Plate and Closing the Tube
Seems I like to work best at night , as I had time early in the evening to continue with the project, but it felt wrong with the Sun being out. Starting at 11:30 pm, I prepped to return the Corrector Plate back on.
Looking at the collar, it's seen a lot of duty, nicked, scuffed and paint coming off… it really needs a fresh refinishing and paint job - but not for this project.
Perhaps in the fall - then I can blow out the inside of the tube.
I clean the front collar/cell… and it was quite dirty. The cork base still looked good and it slipped on nicely on the tube, with all the old and new holes aligning nicely…
All my screws and hardware were safely organized in my little vial case, but I was confused on why there were two different size bolts in the same vial 2nd to last in line… (more on this later).
I bolt back on the clips and single screws around the collar and permanently attach the side control rails now…
Nice, solid and now more confident in carrying and guiding the C11…
I like to note what I did and when on my projects. Throughout my home are dates and signatures behind window sills, drywall and subfloors. This project is no exception and I write behind my Astro business card the project, date and sig…
I place it under the front collar lip and covered with the mounting rail…
(More on those two different sized screws…
In a vial, I had four similar screws, but two were a bit shorter, but I did not know why. I installed the mounting rail on to the OTA, unsure why the discrepancy… but it was to be clear soon. Down by the Primary mirror side, I was screwing down one of the larger length screws for the mount rail, and noticed that the screw was heading for the lip of the mirror - with just a scant couple of millimeters to go before hitting it…!
And there was still some thread to go… dang!
I understand now. Shorter length screws Mirror side, larger ones up front.
Make a note kids…
Next is the re-installation of the Corrector Plate, but first… some more cleaning with tape…
… and some more…
It looks good, but I'm sure some debris will find it's way onto the mirror when I close up…
I remove the plate from the pizza box and give it a dusting. Still looks clean, but dust just settles everywhere… even a minute in the open, dust settles down. (Must learn not to shed skin cells so readily.)
I wanted to sign the Mirror before I returned it, but in all the excitement… I forgot. But, not this time, and I put my moniker along the edge of the plate…
I dig it.
I brush off the rear of the plate again, (can't away from the damned dust), and quickly seat it in the cell/collar. Following the marks I made before I took the plate out, It looks good and in a similar position. I place the cork spacers back in…
I clean off the ring holder and install…
Using just enough torque to have the screwdriver slip off the screw when tightened enough.
It's all put back together…
I examine the beast… and yep..I got some dust behind the Corrector Plate and on the mirror… but some things just can't be helped…
This took longer than I expected, but only because of the additional auxiliary enhancements. The actual cleaning was not as difficult as expected and the whole instrument is cleaner than it has been in years. I would like to have painted it, but I just wanted the project ended, as there are a host of other projects around the estate that needs my attention.
I'm hoping this scrubbing enhances the viewing, making good views great ones - and with all that haze and crud removed - just gotta be. There is a ever so slight haze on the primary mirror, but I will not attempt to remove that.
It's cloudy out now in Chicago, so a test run will have to wait… but glad it's over!…
Update on performance coming soon.
Now… some deserved sleep.
The initial shake out session of the cleaned and modified C11 has been completed and can be found here: http://astronomer.proboards.com/index.cgi?action=display&board=StarParty&thread=2766&page=1
Full narrative at the above link, but it needs serious collimation.
The newly installed handles and rails are great though…!