Back to Home

ATM Forum Message

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button

Home | Discussion Forums | Amateur Telescope Making | Post

Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora
Bonding Glass

Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To
Posted by Jarvis Krumbein on February 2, 2002 00:09:06 UTC

Don't even think about bonding two pieces together except by the fusing method where the glass is actually fused together in a furnace and then re-annealed. Using any type of adhesive, epoxy etc., is doomed to failure because of the vast differences in expansion rates of the glass and the adhesive.

Your best bet is to wait for the 19mm glass although a number of mirrors have been successfully made, including the size you're doing, with glass as thin as 12mm. Extra care must be used when grinding and polishing to support the glass so that it is not distorted by the pressures needed. You would also need to be very careful with the cell design with such a thin mirror. The last point is to not try to make a "Fast mirror". You want to hold the depth of the center to as little as possible. This would probably mean an f-ratio of f8 although f6 is not out of the question if you're very careful.

Good luck,

Jarvis Krumbein,

Follow Ups:

    Login to Post
    Additional Information
    About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
    Unless otherwise specified, web site content Copyright 1994-2023 John Huggins All Rights Reserved
    Forum posts are Copyright their authors as specified in the heading above the post.
    "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
    are trademarks of John Huggins