Fixing up a '60s 4.25 ES newtonian
Posted 07 July 2004 - 12:14 PM
I'm using an Edmund Scientific 4.25 Newtonian on an equatorial bought for $5 at a yard sale. After cleaning off the spider webs, and cleaning the primary mirror, it works.
I have only one eyepiece for it, and the secondary mirror is a bit scratched up. (The secondary is mounted on a single rod, rather than a spider, and the rod is bent). Can anyone offer me advice on how to proceed?
Thanks to all!
Posted 07 July 2004 - 01:03 PM
Congrats on that scope. I recently purchased a mid-80's 4" Celestron Cometron OTA in excellent condition for $65 from an Astromart seller. He'd rarely used it and to my surprise the mirrors were in perfect condition. I also bought a small EQ mount for $65 from another seller. I stripped the black lacquer off the wood legs and gave them a nice coat of stain & sealer. Man does it look classic now! I'll be giving it to my son in August for his 9th birthday. Bringing this scope back to life has been a blast. Hope you enjoy yours as much, and good luck with the restoration.
Posted 07 July 2004 - 04:02 PM
Posted 07 July 2004 - 04:39 PM
Posted 07 July 2004 - 05:08 PM
All About Telescopes has been called "the amateur astronomer's bible," our classic 200-page book is a highly-illustrated and easy-to-understand guide. Contents include: Getting Acquainted with the Telescope; Observing the Sky Show; Photography with your Telescope; Mirror Grinding and Testing; Telescopes you can Build; Telescope Mounts; Collimation and Adjustments; Telescope Optics.
Posted 07 July 2004 - 06:31 PM
It originally came with a 25mm Kellner, a 12mm Ramsden and a 6mm Ramsden eyepiece, a 2X-3X adjustable barlow, a planisphere and an owner's manual. It was an awesome scope. I had seen all the Messier objects by the end of the first summer I owned it. In those days, the Red Spot was crimson colored, so easily seen at low power.
My secondary mirror wasn't even a mirror--in those days, it was a prism mounted with the "V" away from the primary mirror so the bottom of the prism acted like a 45 degree mirror. I can't remember whether or not it was aluminized--it probably was.
The 1 to 1-1/8" diameter secondary mirror does not need a spider to support it--a single stalk is just fine. But collimating it is defintely not an easy job, because it entails bending the stalk. A spider would definitely be easier to deal with.
Wow!! What good old memories!
Posted 07 July 2004 - 06:42 PM
Posted 08 July 2004 - 12:24 AM
Thanks to all for the replies!
Posted 08 July 2004 - 12:41 PM
I remember when I could remember stuff. At least, I think I do...
Posted 19 July 2004 - 07:17 PM
When I purchased my Edmunds reflector in 1977 it was about 30 years old, making it a late 40s vintage scope.
Posted 20 July 2004 - 02:37 PM
Posted 25 July 2004 - 11:08 PM