Definitely enough to go off here to get started.
I've got some glass on the way - so I think I need to start preparing my scaled down fixed post turntable for that (I want to practise the procedure for the larger mirror).
Also like Gleb suggested, deflectometry against test patterns will definitely be my favoured method (especially as I have experience with computer vision with 3D geometry). I have some ideas here and will post methods, results and source code.
Concerning supports -
* Silicone - I'm planning to use silicone washers to mate the captive steel bolts to the glass (the bolt is captured by the back layer of glass in my glass sandwich)
* UV glue - this would only be for between layers of glass, not between the glass and external structure
* Astatic - very interesting! I've come across the constant force vs constant position problem on other projects also. I think the counterbalance system might be too complicated this time since we need to support multiple orientations. Again, might be something to think about or adapt later.
* 18 points - this is certainly possible. It looks like groups of 3 around each of the 0.6 R positions. I'll have a look into this later.
* Whiffle-tree - looks interesting and feasible. I'll have more of a look into this later when working on the external structure / stewart platform assembly
* Paul Yoder's book has a lot of relevant content (flipping through the contents on Amazon). His other book "Opto Mechanical Systems Design" is available in the national library here and also discussed mounting large mirrors. I'll try to spend some time with that.
So to summarise. The sections of work as I see it now are:
* Measurement (spherometer gauges, deflectometry with reflected patterns, if required : interferometry methods e.g. Fizeau)
* Glass assembly (FEM, water-jet cutting, glass suppliers, mounting points, UV glue)
* Grinding and polishing (fixed post turntable, grits, 3 flats method, pitch lap, wet room)
* Silvering (Angel Gilding kit, mounting and rotation jig)
* Backing structure (suspension points, whiffle-tree)