66mm Secondary?

[Malcolm]

Hi, I'm looking for a 66mm secondary. Out of a 10" AOS telescope. I did send both the primary and the secondary to Palmway Optical for re-coating but the secondary has come back in much the same cloudy condition so maybe it wasn't possible to re-coat it. It must be an odd size and I don't really want to have to replace the holder and possibly the spider as well.

It might be possible to carefully remove the holder flange and have a slightly larger flange 3D printed and glued into place as the holder looks like some sort of plastic material. That way I could maybe use a slightly smaller sized secondary. Thoughts on this or where I could get the correct size without having to take out a second mortgage? T.I.A.

[billdan]

You can get a 68mm secondary with holder ready to install from Teleskop Express in Europe. The price shouldn't break the bank, 83Euro.

https://www.teleskop-express.de/shop/product_info.php/info/p10209_TS-Optics-Newtonian-Secondary-Mirror-D-68-mm---prepared-for-the-installation.html

Cheers
Bill

[astro744]

66mm is 2.6". This is a standard imperial size and is readily available from any U.S. source. What type of secondary holder do you have? Is it a proper holder or is it simply glued?

Try http://www.telescopes-astronomy.com.au/telescope_build_construction_help_p arts_accessories.htm

The 2.6" is not shown but could probably be ordered or he may have one.

[Malcolm]

Good one. T&A have a 65mm. Perfect. :-)