Re: ATM making a flat secondary for a newtonian

["Bill Prewitt" <bprewitt@neo.rr.com>]

This link may give some ideas
http://www.starlightoptical.com/diagonal.htm

You will need to polish on pitch, not pads.
Often you can find a good-enough flat by cutting several ellipses from plate
glass....then pick the best.
This can avoid a turned edge

           Good luck,
            Bill Prewitt
My webpage of telescope making and caving
http://home.neo.rr.com/imaging

> How do the pro's do it?
>
> It may seem easier to buy one, but here in South Africa it is difficult to
> get scope parts and extremely expensive if you are able to find someone.  I
> also have a good source of motors/metal to build grinders with.
>
> Garth
> (Poor science student in South Africa)
>
>
>