Re: [ATM] Mirror cell for an 8" mirror

[Ross Sackett <rsackett00@yahoo.com>]

I think you should go with the simplest solution that
leads to a fully adequate result, which in this case
was your original idea of three points at 60%.  

While the worst-case error pointing at the zenith is a
little greater than the PLOPtimized cell at ~40%, the
mirror is much less likely to get hung up on your edge
supports as you collimate it, which is a common
problem with 3 point cells with the pads closer
together.  

If you really want to complexify it and toss in more
points, PLOP says 6 points will support it better than
9.  If you want to silicone the mirror to a plywood
carrier you could use the 40% radius and forget about
edge supports, but then you need to be concerned about
dimensional changes due to humidity (and more dabs of
silicone will only make the situation worse).

Ross

_______________________________________________
ATM mailing list http://www.atmlist.net/