ATM How thin is too thin?

[macaddicted <daviddesign@mac.com>]

I asked this question within a previous thread. I am considering buying the
8"/16" blank set from Dan Cassaro. I have received opinions going both ways
on whether a 7/8" thick blank is too thin for a 16" mirror. I would like to
grind a reasonably fast (f/4.5-5.5) mirror. Dan has been well spoken of
here, and has been prompt in answering any questions I have.

I have been to Mel Bartel's thin mirror site, so I know a mirror in the
range I am thinking of is possible. However, I am not Mel Bartel.

I am planning to do the 8" first to learn proper technique and work out the
bugs (as I said in my other thread). I know that you have to take the time
to learn how the process works, and how to work the process. This is what
the 8" is for. Once it is finished I may turn it into a scope for my
nephew's future use (8 years old and already getting the astronomy bug- I
must be contagious). After I know I can do this smaller blank I will move on
to the larger one.

Any advice you can give is appreciated.

Thanks

Dave
macaddicted