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There is very little activity since I made the plaster tool. I am such an enthusiastic guy!

The tool is fully cured and ready to be coated.
I bought Araldite from a local store and applied it on the back surface, just to test it. Kept it away for one day to cure. But I was not very much impressed. Maybe the epoxy didn't hold good enough to the disk because of the dust that I did not remove before applying it. So next day, I removed the epoxy layer completely and it was then that I was really amazed. The whole epoxy had made a strong layer on the surface. I had to literally peel the layer off and then I realised that this is a very good water proofing material. Actually I had earlier doubted that because all the shop vendors told me that Araldite would not stick to POP.
Next, I sand papered the back surface a bit to make it look smooth and then I filed it again and pressed it to make it a bit shiny. Now I am very much sure that there are no loose particles on the surface and I am ready to apply the coat again which I'll be doing tonight.
Meanwhile, let me document the websites that I referred during all my reading. Though the best website is Stellafane, I would also like to thank the following people for sharing their knowledge:

• The ATM's Workshop
• Making a Tile Tool By Roger Herzler
• Plans for building a Sidewalk Telescope By John Dobson
• How To Build A Telescope By Olle Eriksson
• NOTES FROM TELESCOPE MAKING WITH JOHN DOBSON
• Norm's 8" Dob
• Fraser Valley Astronomers Society (There are some very good resources here)
• Making A Reflecting Telescope By Kartik Patel
• Making a Tile Tool By Jason Hissong
• So you really want to build a Telescope Mirror By Bob May
• the ATM Site
• Making 8-inch Newtonian Reflector By Toshimi Taki
• Herb's Glass and an 8-inch mirror By Herb Johnson
• GRINDING AN ASTRONOMICAL TELESCOPE MIRROR By Larry Gilstrap
• Mark's Notes for the Amateur Telescope Maker By Mark T. VandeWettering
• Complete Plans for building a Dobsonian Telescope By Ray Cash
• NEWTONIAN TELESCOPE DESIGN PLANNER (v/IE1.3) By Jim Fly Very Nice
• Telescope Construction By Bob May
• Building a 12.5" Dobsonian Telescope By Dan Vint
• Amateur Telescope making By Berthold Hamburger
• My ATM Blog By Satish K Pagare
• 8" F6 Mirror Grinding By Dr Debug
• Very good videos by Francis J. O'reilly on Youtube
• Telescope Simulator
• ATM By Ben McIlwain
• BBC Sky At Night Magazine's Mirror Grinding Video

Making of Plaster tool

After reading a lot (I mean A LOT) about Telescope making, I finally made up my mind to build one for myself. My dad had bought me a telescope when I was about 13. That was about 19 years ago. It was (is, rather) really an astro-terrestrial scope and I really enjoyed watching the moon in it. Little did I realise that this small telescope is going to make a very big impression on my heart. Maybe someday I'll post a pic of my first scope.

Later I got myself a Binocular (pics later). This boosted my interest in astronomy to such an extent that I started tracking the skies on a daily basis.
Finally, I decided to have my own scope so that I don't have to wait in long queues to watch the Saturn rings.
Now I had to think about how much can I afford to spend on a decent scope. I was looking at an 8" reflector with Dobsonian mount. A decent one could easily go beyond 40K Rs. This is way beyond my budget as I have other projects lined up.
So I thought that with a little extra efforts, I can save money and also satisfy my intellect.

Yes, I decided to build my own telescope, right from making my own mirror. So I bought this 8" mirror making kit for around 3k. The kit gave me 2 glass blanks, some abrasives and the pitch.

This is the Blank measuring 200mm.

Now since I have read A LOT, I decided to save one glass blank and use a plaster tile too to do the grinding. So I bought POP and some other stuff from a local supplies shop and started with it. Created a Dam using ordinary cardboard. Applied vaseline on the glass surface as I don't want the plaster to stick to the glass. Insulated the glass with a transparent plastic paper.


The guy in the store told me that the POP would set in about 15 mins. But I learnt (the hard way) that it started setting in less than 5 mins. So I had to literally scrape the POP from the mixing container and pour into the dam. As I had expected, the disk was not even close to the mark and I had to throw it away.
Next I went out and bought another POP bag. This time I was determined to keep it in slurry form till I poured it in the dam.



This is the final product. I have kept it aside for curing. There won't be much activity here for the next couple of weeks till the disk is ready for waterproofing.