[ATM] Hoping to Grind a Mirror

[Kampala Uganda <kampalaliving@gmail.com>]

Hello all,
 I am hoping to make a 6" Dobsonian telescope, but I need some pointers and
advice. I have a photocopy of the relevant chapters from the Texereau book,
and I think I understand the (basic) steps required. However, I need to
improvise on the materials needed, and I don't know where to start. So here
we go:
 1. Glass: The thickest glass I can find here is 1.2cm [BTW I am in Uganda,
Africa, so life here requires improvisation]. The book suggests for 6inch
glass that I want to build, I need about 1 inch thickness. Is this
absolutely necessary? If so, what is the maximum diameter that I can have
with 1.2cm thickness?
 Furthermore, no one here can cut me a circle! However, I found on the
internet some procedure for cutting the glass using a rotating can with a
sharp edge, and lots of water with abrasives. Does this sound feasible?
 2. Abrasives: I cannot find the carborundum abrasives. Even the eyeglass
shops don't grind their lenses, they import them and just cut them to shape.
I was thinking for the rough grinding, I could use fine sand (ditto for the
cutting the circle above). Is this possible? For the fine grinding, I was
thinking of a paste that is used for smooth grinding car engine pistons
(when they have a carbon buildup). I have no idea what the size of the
particles in the paste would be, and how hard they would be.
 Is there any other sources of abrasives? There is a relatively well
developed automotive maintenance industry here. Also there are knife
sharpening stones, which may be carborundum. I will use them for bevelling
the edges, but I don't know if there is any way I can get powder from it
while controlling of the particle size (upto 2 micrometer?).
 3. Polishing: Are there more traditional methods to produce the polishing
agent: rouge? Its chemical composition is Fe2O3, but surely the size of the
particles also matters? The only place I have not investigated is jewellers
(I am sure there are some).
 There is an architectural glass shop here, but they said their cerium oxide
is solid blocks that their machine takes, they don't have powder cerium
oxide.
 4. After this I have to start worrying about the reflective coating and the
eyepiece, but to be frank, I will have my hands full figuring out (no pun
intended) items 1-3. From the little I have researched on the net, I will be
able to make the reflecting surface from silver nitride. However, with the
eyepiece, would I be able to make that using the same process as the two
mirrors?
 Buying/receiving from outside the country is almost impossible, as the
postal system is unreliable at best. In any case, it would be great if I can
make it with local materials.
 Thanks!
 K.
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