Re: [ATM] Polishing / Figuring Simulator

[Mark Holm <mdholm@telerama.com>]

Richard wrote:

> I am currently looking at finite element analysis of a fixed
> mirror with a lap resting on it at various radial positions.
> Looking at the surface stress the one striking thing that jumps
> out is how the stress soars at the very edge of the mirror as
> soon as the lap starts to overhang. The edge stress is 7 or more
> times higher than just an inch away on a 20 inch mirror.
> 
> Adding a chamfer actually raised the maximum stress but moved it
> to the chamfer face, with an overall lowering of maximum stress on
> the mirror surface. It was lowered still further by applying a
> radiused fillet to the edge rather than a chamfer.

Is that stress in the glass, or stress in the lap or pressure between.
All of the above might be interesting, but not necessarily equivalent.

-- 
Mark Holm
mdholm@telerama.com

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