Saturday, February 17, 2007

My first telescope - Part II

Fast forward to 2005, the year I decided to pick up where I left off in 1987. The good old telescope was stored at my dad's house, at a nice little corner in a dark store room. I manage to drag the thing out, opened the optical tube and looked at the primary mirror. It's got some dust and fungus on it, the same goes for the secondary mirror. I dismantled the optical tube and mount and took it back to my house in Shah Alam. I spent a whole weekend cleaning it. The parts and screws had some rust on them and I must have used up half a can of WD40 cleaning them! The fibre glass tube is still in very good, sturdy condition despite sitting in the dark for close to 15 years! But outer coat of white lacquer had turned a bit yellowish.

The Meade Starfinder 826C, 8 inch f/6 with Rigel Finder.

Cleaning the primary mirror was the most crucial part. Having gone thru various web sites and consulted experts from all over the world in forums, I prepared the necessary – lots of distilled water, a bit of dish washing liquid, clean bucket and cotton, lots of it.

I removed the 8 inch primary mirror from the cell and immersed it in a bucket of distilled water, added 2 drops of dish liquid and used cotton to gently wipe or rather drag the cotton over the mirror surface three times while underwater. After that, rinse it with distilled water and leave it to dry. Worked like a charm – not a stain.

The secondary mirror was bad. After cleaning it the same way, the fungus was still there. So I sent it to Mr. Looi at Infinity Infocus to clean it using industrial grade ethanol. The result was much better but the damage was already done.

This the the view from the focuser, note the yellow stains on the secondary mirror.

After more than 15 years, the grease on the focuser was dirty and dry. I took the focuser apart to clean and put in a new layer of grease – Panef white lithium grease to be precise. It lasts longer and provider better lubrication that the regular yellow/brown color one. You can get it from Ace Hardware store. I also cleaned the finder scope and got rid of most of the fungal growth.

Next, fixing the clock drive ….

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