Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

6" Tinsley Saturn Cassegrain Restore

  • Please log in to reply
369 replies to this topic

#1 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 23 March 2015 - 09:30 PM

Yes... Another Tinsley thread!  Rather than hijack the others, I'll use this one to pester y'all...

 

Parts and accessories are arriving. But that's the easy part. Here's the starting point:

 

 

Attached Thumbnails

  • 15CM-CC-P102CN - OTA Before Restoration.jpg

  • bob midiri, BarabinoSr, Jim Davenport and 10 others like this

#2 davidmcgo

davidmcgo

    Gemini

  • *****
  • Posts: 3,207
  • Joined: 09 Oct 2004
  • Loc: San Diego, CA

Posted 23 March 2015 - 09:46 PM

That is going to be a stunner when you are done Bob!  Can't wait to see your progress!

 

Dave


  • Geo31 likes this

#3 clamchip

clamchip

    Voyager 1

  • *****
  • Posts: 10,418
  • Joined: 09 Aug 2008
  • Loc: Seattle

Posted 23 March 2015 - 11:05 PM

Very neat!

 

Robert


  • mattyfatz likes this

#4 bob midiri

bob midiri

    Skylab

  • *****
  • Posts: 4,078
  • Joined: 17 Jun 2004
  • Loc: pa 19320

Posted 24 March 2015 - 06:38 AM

Looking forward to this thread!!!



#5 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 21,896
  • Joined: 29 May 2012
  • Loc: Under the Blue Moon of Kentucky

Posted 24 March 2015 - 07:04 AM

Cool! I bet you could make a nice brass finder for it that would look pretty close to the original. You might even be able to use a set of Unitron 40mm Finder rings painted the same blue-gray color as the tube.


  • mattyfatz and Bomber Bob like this

#6 Rich (RLTYS)

Rich (RLTYS)

    Fly Me to the Moon

  • *****
  • Posts: 7,105
  • Joined: 18 Dec 2004
  • Loc: Mayo (Maryland)

Posted 24 March 2015 - 08:15 AM

Interesting looking scope. Good luck on your new toy.  :waytogo:

 

Rich (RLTYS)


  • Bomber Bob likes this

#7 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 08:15 AM

I bet you could make a nice brass finder for it that would look pretty close to the original.

 

Terra The Mind Reader:  Actually, I got a small brass scope from Sean with vintage rings that'll be fancied-up.

 

This weekend is Brass Saturday.  I've been reading about using a vinegar & water soaking solution on brass, and I'm going to try that first.  Notice the long stain on the cell & focuser assembly -- I'm hoping this will help fade / remove it.

 

To be preceded by Tube Thursday.  Gonna check with some local body shops on smoothing and repainting the exterior - if they can match the original paint color.  Would y'all go with a glossy or a satin finish?


Edited by Bomber Bob, 24 March 2015 - 08:46 AM.

  • mattyfatz and bremms like this

#8 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 08:48 AM

While I'm thinking about it:  Does anyone have a catalog, ad, etc. showing the 6" Cass?  I'd like to try and nail down when this size was sold.


  • mattyfatz likes this

#9 Adam S

Adam S

    Vanguard

  • *****
  • Posts: 2,484
  • Joined: 21 Dec 2005
  • Loc: ABQ, NM

Posted 24 March 2015 - 09:20 AM

I missed this the first time you posted.  Great looking scope,  brass would really make it special.  It's too bad that there so little information about this company.  This'll be a fun one to watch.



#10 clamchip

clamchip

    Voyager 1

  • *****
  • Posts: 10,418
  • Joined: 09 Aug 2008
  • Loc: Seattle

Posted 24 March 2015 - 10:19 AM

Take a look in Robert's site here:

http://geogdata.csun...taire/classics/

scroll down to "1930's Tinsley catalog" and

the Cassegrain's appear to start at 10 inch aperture but the same style as your 6.

Thats old!

 

Robert


  • mattyfatz likes this

#11 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 10:46 AM

Yeah, I got a copy of that 1930s catalog; and, I've scoured the Internet for old ads & such, but I can't find anything from Tinsley about the 6"...

 

Makes me wonder:  Was it more of a custom order?  Or, a size they tried briefly, and it didn't sell?  Wish I knew more about the company...

 

It has the 30s-40s style (and lots of brass!), and is well made.  I'll enjoy using it, for sure.  And though I'm gonna fuss & cuss, I'll enjoy the restoration, too.

 

The GEM & pedestal are not as old as the OTA.  But for now, I'll take functionality over authenticity!


  • mattyfatz and bremms like this

#12 Geo31

Geo31

    Voyager 1

  • *****
  • Posts: 11,594
  • Joined: 28 Jan 2013
  • Loc: Willis, TX

Posted 24 March 2015 - 11:28 AM

May have been a guide scope?



#13 Geo31

Geo31

    Voyager 1

  • *****
  • Posts: 11,594
  • Joined: 28 Jan 2013
  • Loc: Willis, TX

Posted 24 March 2015 - 11:31 AM

JW, if you don't have any engraving on the brass, get some silver tarnish remover.  It's lighly abrasive and worked wonders on the nearly black stained brass draw tubes of my RV6 rescue scope.  Follow up with a little Nevr Dull (also very lighly abrasive) and it should turn out looking fantastic.

 

If you have engraving, you want to avoid any abrasives if you can because edges will become less sharp.


  • Bomber Bob likes this

#14 bremms

bremms

    Fly Me to the Moon

  • *****
  • Posts: 5,251
  • Joined: 31 Aug 2012
  • Loc: SC

Posted 24 March 2015 - 12:06 PM

Wondering if it was a guide scope or secondary scope for the bigger cassegrains. I looked too and found nothing on the 6" Cass from that era. George's recommendations for the brass are very good. Sure has been some Tinsley love the past couple weeks. Maybe we can start some kind of Tinsley database. ATS forum members may have some info, I have a source here that may know a little bit.

Yeah, I got a copy of that 1930s catalog; and, I've scoured the Internet for old ads & such, but I can't find anything from Tinsley about the 6"...

 

Makes me wonder:  Was it more of a custom order?  Or, a size they tried briefly, and it didn't sell?  Wish I knew more about the company...

 

It has the 30s-40s style (and lots of brass!), and is well made.  I'll enjoy using it, for sure.  And though I'm gonna fuss & cuss, I'll enjoy the restoration, too.

 

The GEM & pedestal are not as old as the OTA.  But for now, I'll take functionality over authenticity!



#15 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 12:44 PM

It sure could be a big guidescope on an even larger reflector -- I actually hadn't thought of it.  That would explain the lack of info.  Maybe these were custom-made for institutional use.  Otherwise, I would think the 6" would have been popular among amateurs for cost & logistical reasons -- if Tinsley could have sold them for a profit.

 

The tube has holes for finderscope mounts, but those may not be original.


  • mattyfatz likes this

#16 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 21,896
  • Joined: 29 May 2012
  • Loc: Under the Blue Moon of Kentucky

Posted 24 March 2015 - 02:03 PM

Is it a Gregorian? Around F20 to F25? How big is the secondary? It could have been a specialized solar scope?
  • mattyfatz likes this

#17 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 02:38 PM

Terra, it was listed as F20; the secondary is exactly 2" diameter.  The mirror set is a mystery -- not a Tinsley, unfortunately.  It's the one I posted about with the Delta-Lambda label from a recoating... probably in the early to mid 70s.


  • mattyfatz likes this

#18 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 21,896
  • Joined: 29 May 2012
  • Loc: Under the Blue Moon of Kentucky

Posted 24 March 2015 - 02:43 PM

I wonder what the specs were on the original. The tube looks much longer proportionally to the diameter than Steve's old/Marc's new Tinsley DK that's is also running in a current thread. It looks like your mirror set at F20 should match the tube dimensions pretty well. That is why I was wondering if it was a Gregory-Cass. If it goes back to the 1930s that would make sense too as GCTs were more popular then. Is the secondary concave?

Edited by terraclarke, 24 March 2015 - 02:45 PM.


#19 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 02:48 PM

The first time I saw Bob Midiri's photos of it, I thought it looked 1930s -- and Art Deco.  Don't know when Tinsley changed the OTA style, but I suspect toward the end of the 1940s.  In any event, my restoration will be Art Deco in style & color.  I should know by COB Thursday if any of the local body shops I trust can replicate the paint job.  Once that's set, the GEM & pedestal will follow.



#20 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 21,896
  • Joined: 29 May 2012
  • Loc: Under the Blue Moon of Kentucky

Posted 24 March 2015 - 03:04 PM

You have the Tinsley mount and pedestal that went with it or are you making one?

#21 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 04:32 PM

No Tinsley mount - dang it!!  I'm using the GEM from a Meade MTS series scope.  It can carry the load, and it has the big RA circle and conical polar axis, so it'll look complementary.  The pedestal & its base are the surprise Art Deco element.

 

That is why I was wondering if it was a Gregory-Cass.

 

Me, too.  The only mirror testing has been on the bench.  But my rough measurements are compatible with the Tinsley OTA.  I shouldn't have to move the secondary cage or drill new holes.  I'll know for sure after I get the mirror cell modified.  The D/L is much thicker than the original... BUT, the secondary is exactly the same size... I may confirm your GCT idea in the next few weeks.



#22 Terra Nova

Terra Nova

    ISS

  • *****
  • Posts: 21,896
  • Joined: 29 May 2012
  • Loc: Under the Blue Moon of Kentucky

Posted 24 March 2015 - 06:04 PM

You can tell by looking at your secondary. If its concave its the Gregorian design, if its convex its likely a Dall-Kirkham.

So you are going to put it on a fork mount. That is interesting. How are you going to mate the tube to the fork? I would assume you will create a large clamshell to hold the tube? Balance will be an issue so you may also want a sliding weight balance system. These old long casses were generally on GEMs.

Check out the lower picture of the 1940's Tinsley advertisement. It's a cass on an GEM and it looks an awful lot like your tube.

http://www.philharri...net/tinsley.jpg

Edited by terraclarke, 24 March 2015 - 06:14 PM.

  • Geo31 likes this

#23 clamchip

clamchip

    Voyager 1

  • *****
  • Posts: 10,418
  • Joined: 09 Aug 2008
  • Loc: Seattle

Posted 24 March 2015 - 06:37 PM

I have a 1949 Tinsley catalog on its way that may shed some light on your 6 inch.

Its coming from Canada and expected to be delivered around April 11th.

 

Robert


  • Terra Nova and Bomber Bob like this

#24 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 24 March 2015 - 06:49 PM

Now that I look at it, the Meade GEM was the later one used with the reflectors -- not the first version, and not the MTS-SN series scopes.  Both axis housings are conical.  It also has the battery-powered RA drive.

 

The secondary mirror is concave.  As I've mentioned before, the primary is thicker than the Tinsley would've been.  In fact, I think it's thicker than the 8" one I ground years ago.  Also, it doesn't look like Pyrex to me -- the glass seems denser.  Wish I knew more about their history!!

 

Yeah, my Tinsley looks like the one in the ad.  It doesn't have holes from a counterweight system, but it does have them for a finder at the same relative placement as the larger versions.  I have a set of felt-lined aluminum rings that fit the tube snugly.

 

The old Jaegers finder rings fit the existing holes - no drilling required.  She'll have two finders:  A small brass one for show against the OTA paint.  And a vintage achromatic with an old SPI-looking focuser mounted to the tube rings.


Edited by Bomber Bob, 24 March 2015 - 06:57 PM.

  • BarabinoSr and Vesper818 like this

#25 Bomber Bob

Bomber Bob

    Hubble

  • *****
  • topic starter
  • Posts: 16,841
  • Joined: 09 Jul 2013
  • Loc: The Swamp, USA

Posted 25 March 2015 - 06:15 PM

Thanks to Sean & Brian, the two finder scopes are here.  The mounting rings are suitable for the time period, and I'll use brass hardware.  Setting out first thing tomorrow to find a tube painter.  I may go ahead and try the vinegar soak as well, but I will track down the silver tarnish remover & Never Dull.  I only have two large brass pieces, and neither has any engraving, so the abrasives shouldn't do any harm.

 

I was going to paint the finder rings gloss black, but it sounds like the older Tinsley's used crinkle finish.  I'll do some more research before rattling the cans.

 

The brass unit has a CA of 24mm.  The painted one is an old 50mm spotting scope (has holes on the bottom for a 1/4-20 bracket).  It's built like a tank, has a nice R&P, and Brian included a 60s RAO KE22 that's black versus the lime green that came with my 6336.

Attached Thumbnails

  • Finderscopes - BEFORE Restore CN1.jpg

Edited by Bomber Bob, 26 March 2015 - 08:19 AM.

  • mattyfatz and Terra Nova like this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics