Cleaning SCT mirror on Meade LX200 with Internal wash bay
I needed to clean the primary mirror of the 12" LX200 but did not want to remove the primary mirror so I made this water proof internal wash bay for cleaning the mirror using a sheet by of 0.5mm thick plastic. It takes around 20 minutes to make and install the wash bay and 5 minutes to wash the primary mirror, it was easy and worked very well. (see the photos attached)
After very carefully marking the corrector position remove the corrector
1. Measure the circumference of the primary mirror using a strip of paper or cardboard and mark a point, you don't want it too tight to slide past the primary mirror so add 3mm to the length.
2. Measure the circumference of the inside of the corrector housing at the end of the front of the OTA tube using a strip of paper or cardboard and mark a point, you don't want it too tight to slide past the opening so remove 3mm from the length.
3. Measure the distance from the primary mirror edge and the corrector housing.
4. Due to the primary mirror being larger than the corrector housing you will need to mark the plastic sheet from a central line to form a slightly conical shape, then add 100mm to the front to allow water to flow out of the OTA and add 50mm to the back to allow the wash bay to slide past the primary mirror to the rear cell. Also add a 10mm tab down one side to allow the sheet to be attached together with gaffa tape.
5. Carefully slide the internal wash bay through the corrector assembly and past the primary mirror
6. Do a similar procedure to make a tube to cover the baffle tube and attach to baffle using gaffa tape.
7. Place the OTA in a slightly downward position with a bucket on the ground at the front and carefully use a large syringe to wash the mirror with cleaning solution or mild pure soapy water then with another large syringe carefully wash the mirror with pure water and allow to completely dry then carefully remove the internal wash bay and replace the corrector to its original position.
|