Re: ATM 3-Vane or 4-Vane Spiders

["Jim Miller" <jim@jtmiller.com>]

in the US try www.cstsales.com or
http://www.deltronix.com/public/acp/acp-cat.htm

i've been happy with purchases from both.  btw, tell them what the
application is and they both will spend some time with you going over
alternatives, suggestions for construction, adhesives, etc.

dark skies

jtm

----- Original Message -----
From: "Vegos" <astro@rvi.net>
To: <atm@shore.net>
Sent: Thursday, October 11, 2001 11:47 PM
Subject: Re: ATM 3-Vane or 4-Vane Spiders



I'd like to field a different question, mabye less interesting, I don't
know?

Bruce Sayre's new design for the 22" scope uses 3 vane spiders.  This is the
first time I've seen 3 vanes on a scope so large.

Personally I prefer 3 vanes to 4 and have been trying to figure out 1.) If 3
vanes will suspend the large 2.6", 3.1" etc. secondary without vibration and
movement problems, 2.) Where could I find carbon fiber sheet for vane
construction?

I intend to use 3 carbon fiber vanes on a 14.5" scope just to test 1. above.
If constructed light and tight, it should fly, eh?

Any thoughts, ideas appreciated.


Steve Vegos
http://www.rvi.net/~yovw


>
> Paul,
>
> >DIFFRACTION IS NOT AN EDGE EFFECT
> >DIFFRACTION IS NOT AN EDGE EFFECT
> >DIFFRACTION IS NOT AN EDGE EFFECT
>
> I beg to differ. Page 55 in Star Testing Astronomical Telescopes:
> D