Re: Schmidt Corrector Plates
Stephen Dillinger (fmicos!argus!dillinge@uunet.uu.net)
Mon, 10 Jul 95 11:21:16 MDT
> > I've got a general question about making corrector plates. I've always
> > wondered if it would be possible to bypass the vacuum fixture and instead
use
> > blocking pitch to attach a suspended weight from the center of the blank.
It
> > seems to me that it should come close to the correct deformation depending
on
> > where you support the glass. Anyone know if it would work?
>
> Unfortunately, the answer is NO. The plate deforms differently when
> pulled at the center from what happent when it is uniformly pressured
> by the atmosphere. Try any finite analysis program, and you'll see.
I was afraid of that, I know that a force applied at the center would be
different than a uniform force, but was hoping that the thickness and rigidity
of the glass might allow the center force to approximate the "real" thing.
How difficult is it to just grind in the appropriate curve without deforming
the glass at all? As you may be able to tell, I have a real aversion to
warping a large piece of glass (not to mention the expense of having the vacuum
pan made).
One of these days I'll get around to making one... after I'm retired. :)
Steve Dillinger