Anyone recognise this Reflector?

[torana68 (Roger)]

Hi all,
Picked up a old 8" and was wondering if anyone recognises it or its parts? thinking its home made........... has a Unitron focuser, mirror is 8" x 1.5", measures out roughly at F6.5 (distance from mirror to secondary plus from sec. to focuser?), secondary spider is three blade. The finder is nicely made from PVC sections then painted with wrinkle finish black . It has been repaired at least once, holes welded in the tube where a finder scope was and high quality paint applied.It wasnt a roughie..... I was thinking 60's???
Thanks
Roger
http://i83.photobucket.com/albums/j2...s/IMG_0792.jpg
http://i83.photobucket.com/albums/j2...s/IMG_0793.jpg
http://i83.photobucket.com/albums/j2...s/IMG_0794.jpg

[Satchmo]

Yes its circa late 60's tube built by what was then Amateur Astronomer's Supply Co which later bacame Astro-Optical Supplies in 1978. The 37 year heritage of telescope manufacture ended in 1995 I think when the business changed hands last.

[torana68 (Roger)]

thanks, cant find anything on their Reflectors, anyone have a link ? its nice to be able to put a name to the poor old thing.
Roger

[koputai (Jason)]

Looks like a lovely little Unitron 0.965 Ortho eyepiece in that finder, possibly a 12.5mm

Cheers,
Jason.

[Glenhuon (Bill)]

Certainly looks like an Astro optical assembly. My 10" has an identical design of mirror cell. the 10" is late 70's / early 80's I believe. If the mirror is of the same quality as mine (Pyrex) you have a nice scope there, well worth having the mirrors recoated. Astro Optical told me that they only make these mirrors to special order now as Pyrex is hard to find and not cheap.

Cheers
Bill

[spudrick]

Hi definately Astro optical assembly i also have a 10" version of this scope, it also has a Unitron finder. Note the substantial difference in thickness an weight of the steel tube compared to current GSO tubes.

[torana68 (Roger)]

Thanks guys, it came with a 40, 12.5 and 6mm Unitron eyepieces, heavy? its "oh my god" heavy.... very solidly built, even the mirror , being 1.5" thick is very heavy. Ill have to do a search on who to get to do the mirror, Im sure thats been a topic of interest before.
Roger

[Satchmo]

Originally Posted by Glenhuon

If the mirror is of the same quality as mine (Pyrex) you have a nice scope there, well worth having the mirrors recoated.

Definately worth having it recoated if the mirror star tests well.

If you are getting it redone, check that you are getting a Silicon monoxide or Slicon Dioxide overcoat. Don't accept anything less.

Originally Posted by Glenhuon

Astro Optical told me that they only make these mirrors to special order now as Pyrex is hard to find and not cheap.

Astro Optical sold off all there mirror making machinary long ago and shut their optical shop, so special order must mean contracting out the manufacture of a mirror to outside. AstrOptical produced thousands of Newtonian mirrors/ telescopes between 1958 and 1993. I personally manufactured some 350 telescope mirrors at their facility in Crows Nest from 1985-1988.

Re Pyrex availiblity there was a brief period of uncertainty when the Corning factory in UK supplying the world with 2" sheet Pyrex was closed down. Boules of quality borosilcate glass are now being produced to cover the gap by Schott in Germany and Ohara in Japan and sheet 2" will soon be available again for those companies that use sheet. I've always used moulded blanks and there has been no interupt in the supply of that. Its true that the USD $ cost of blanks has practically doubled though.

[torana68 (Roger)]

If you are getting it redone, check that you are getting a Silicon monoxide or Slicon Dioxide overcoat. Don't accept anything less.

thanks for the wise advise, if you have any suggestions on where to or not to go I would appreciate a PM.


Astro Optical sold off all there mirror making machinary long ago and shut their optical shop, so special order must mean contracting out the manufacture of a mirror to outside.

its a shame so much technical knowledge is slowly being lost....
thanks all, Roger

[Glenhuon (Bill)]

Thanks for the info Satchmo. You may have even made my 10" mirror as were not sure of the date of manufacture.
Astro optical recoated it for me with the overcoating and made a nice job of it. All up cost for the recoating of both mirrors was $290 including return postage if I remeber correctly

Cheers
Bill

[Satchmo]

Bill, Your mirror would have been made my time if you think it was made late '70's early 80's.

[Glenhuon (Bill)]

A friend found the complete 10" on a Dob mount in a rubbish tip and gave it to me. Mirror was loose in the tube and covered in dust, but no chips or scratches on the glass. So you made em to last

Bill