81 replies to this topic

[Kasmos]

Refractor focuser easily the most Stone-Age effort I've seen.  Truly an afterthought, i guess because the refractor was a guidescope?

I was interested in the 3” refractor as a classic standalone scope. It needs more restoration than Im capable. I’m very curious about in the actual make .
Glad to see it in good hands.

It's a Edmund and that's an original Edmund focuser.

[Kitfox]

As I said in an earlier post, I did get the rings from Joe Nastasi at Parallax this past week. And along with them, I had to make a decision about the future of this scope-leave a complete restoration as a possibility, or to make it a living, working scope returned to like “new”,  but with modern functionality.

 

The latter is the decision I committed to over the last 48 hours. In order to get the rings on and as far back to the cell as possible, the mount pylon, finder stalk and guidescope rings had to go. Basically had to strip her down to the bare optical tube. 
 

The rings for the guidescope and the finder stalk were easy. And led to the discovery that the tube is DOUBLE wall aluminum.  This is new construction methodology to me, but it allowed attachment of accessories to the outer wall without violating the integrity of the inner wall of the OTA. Not sure how the walls are spaced to maintain concentricity, but it sure seemed like a solid wall until I got the rings off. 

 

And it really became clear when I FINALLY got the mount pylon off. Which was a nightmare. The pylon was held to the outer shell with four bolts, but it was then filled with that hard poly foam like is used for home insulation. Those who are familiar with this stuff know it becomes part of an engineered structure, adding significant strength as well as insulating the buildings.  Well, it made the pylon almost a permanent part of the optical tube.  However, after several hours chipping away at the foam, more than one drop of blood spilled, and a hopeful astronomer nearing total exhaustion, a sudden “POP” and off it came. Hallelujah. All downhill from there, the rail for holding balance weights was also held in place with the same foam fill, along with 4 pairs of dome head screws, but it was easily removed. 
 

Now I have a tube fully bare on the outside, ready for the rings. And I now see how the double walls are stabilized. The space between the walls is filled with this foam. Nice!  At least I now know the structure is stable!

 

Mr. Nastasi’s ring set fits perfectly, and I am really close to setting this monster atop the Losmandy Titan and pointing it towards a planet or two. But the observatory is a few weeks away from being ready. Would anyone short of Andre The Giant consider this thing portable and set it up in their yard?  Hmmmmm 

Edited by Kitfox, 14 September 2024 - 05:43 PM.

[jragsdale]

More pics!! 

[Scott in NC]

More pics!! 

Definitely! This is a cool enough project that many of us would be interested in seeing photographic documentation of the restoration project step-by-step.

[Kitfox]

More pics!! 

I’ll take some tomorrow, subsequent to installing the dovetail you so kindly sent my way!  Gotta clean up the pile of foam bits first; so embarrassing the mess I made!  

[Kitfox]

It is almost manageable now.  ALMOST.  Scott in NC and his son came over Sunday and we discussed what we would each be taking to the Staunton River Star Party (CHAOS) in a few weeks and one option was the Losmandy Titan and this scope.  It sounded like a good idea at the time.  I think I was temporarily delusional!

 

 

 

Edited by Kitfox, 17 September 2024 - 05:27 PM.

[CHASLX200]

Can you even lift it up on a mount?

[Scott in NC]

My son and I tried to lift it and about a foot or two above the ground was high enough for us.

[Kitfox]

Can you even lift it up on a mount?

 

My son and I tried to lift it and about a foot or two above the ground was high enough for us.

 

It is not something I want to do more that once, Chas!

Edited by Kitfox, 17 September 2024 - 06:41 PM.

[CHASLX200]

It is not something I want to do more that once, Chas!

Once you go past 10" things get heavy fast.  I would be scared as i hate D plates and the holders as you never know if they are locked down and the OTA can flop out sideways.  Trying to hike up something high and that big and bulky can be very tricky. At least with open rings it would be much more easy.

[Kitfox]

Once you go past 10" things get heavy fast.  I would be scared as i hate D plates and the holders as you never know if they are locked down and the OTA can flop out sideways.  Trying to hike up something high and that big and bulky can be very tricky. At least with open rings it would be much more easy.

 

That is an option, the Parallax rings are quite stout.

[Scott in NC]

I think the best way to mount this will be to mount the plate first with rings attached, then have two people lift the scope and place it into the rings. Then one person can hold the scope still while the other one closes the rings around the scope. But Steve, don’t try this until you get your observatory set up. And I can come help you if you and your son can’t safely do it together.

[deSitter]

My son and I tried to lift it and about a foot or two above the ground was high enough for us.

Anything that heavy you can drop a few inches

 

-drl

[tim53]

When I put my 12.5" f/23 Cass on my Em-500 mount at Cosmic Acres, i took the primary and cell out of the tube to reduce the weight, since the saddle is at around 6 feet above the floor.  Then, I put the mirror back in the tube and collimated it.

 

-Tim.

[Kitfox]

I think the best way to mount this will be to mount the plate first with rings attached, then have two people lift the scope and place it into the rings. Then one person can hold the scope still while the other one closes the rings around the scope. But Steve, don’t try this until you get your observatory set up. And I can come help you if you and your son can’t safely do it together.

 

Making it a three man job will be nice.  The Titan has a very substantial, but slide in, not tilt in, dovetail saddle anyway, so I can't imagine doing it in one step...

 

...as I have said before, this thing is just going up onto a mount for a few months to evaluate it, condition as-is (which is not too bad for a scope closing in on 60 years old).  Then it either comes down for a cosmetic overhaul and recoating, or it goes out to pasture with our 32 year old Tennessee Walker (take that figuratively or literally, your choice!).  I hope this thing is at the start of another 60 years in it's new home at Kitfox Acres!

[CHASLX200]

I think the best way to mount this will be to mount the plate first with rings attached, then have two people lift the scope and place it into the rings. Then one person can hold the scope still while the other one closes the rings around the scope. But Steve, don’t try this until you get your observatory set up. And I can come help you if you and your son can’t safely do it together.

Best way by far. Even my low mounted C11 is a pain as you can't see over the OTA while mounting it. Never lost a OTA by it sliding down but had them flop out to the side 5 times thinking they were locked in. Lucky never any damage.  Maybe i am doing it wrong with these D plates. I slide the dovetail into the holder by pushing it in sideways not sliding it from the top.

Attached Thumbnails

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Edited by CHASLX200, 17 September 2024 - 06:56 PM.

[Kitfox]

When I put my 12.5" f/23 Cass on my Em-500 mount at Cosmic Acres, i took the primary and cell out of the tube to reduce the weight, since the saddle is at around 6 feet above the floor.  Then, I put the mirror back in the tube and collimated it.

 

-Tim.

 

I have hijacked this thread more than once, so another time won't matter!  That f/23 is gorgeous, Tim.  And it sure seems optically excellent...please post some pics here for those who haven't seen it and tell us a little about the history.   I think no one here will question its status as a classic, even if in design alone.  And, after all, this thread is vested in 12" Cassegrains, anyway!

 

I have a couple of EM400's, and lust after a 500, as well. 

Edited by Kitfox, 17 September 2024 - 07:17 PM.

[deSitter]

When I put my 12.5" f/23 Cass on my Em-500 mount at Cosmic Acres, i took the primary and cell out of the tube to reduce the weight, since the saddle is at around 6 feet above the floor.  Then, I put the mirror back in the tube and collimated it.

 

-Tim.

f/23!!!! Wow!

 

7300mm!

 

400x with an 18mm eyepiece!

 

-drl

[tim53]

Here's an old picture from when I had it mounted on my 8"'s Springfield mount.  Picture by the late Fred Ley.

 

 

I have an old thread where I talk about the build, from several years back, but I can't find it!

 

Optics were made by Ed Beck around 1990.  Tube is Teak plywood with poplar corners (so I could get it all in one 4x8 sheet).

 

I am toying with the idea of putting it back on a Springfield mount with wheels under the tripod so I can roll it in and out of my shop fully assembled.  I've had this Springfield mount head for a long time now, purchased on Ebay around 2010.  The bearing surfaces are 11 inches across, IIRC, ( the laptop is a 17", so not as small as it seems), so almost twice as big as the mount in the above picture.  If I do put it on the springfield, I'd like to rig it so I can remove the tertiary mirror out the back, and put a focuser in there for only 2 reflections for planetary imaging.  I might also poke a hole in the top of the tube and mount, say, a 6" APO on it with a diagonal mirror directing the light cone to the Springfield focuser.  That too could be set up so the refractor could do the imaging while I view through the Cassegrain.

 

Edited by tim53, 17 September 2024 - 10:20 PM.

[Bomber Bob]

My Tinsley 6 is the only scope where I bolt the hinged rings to the mount plate -- no dovetail.  I take off the front ring & bolt it down, then swing it open.  I lift the OTA by the back ring & tail piece, lay the front third in the ring, and use my left had to keep it from sliding off while I close & tighten the front ring.  Finally, I slide the rear ring to its hole, and bolt it down.  But it's a lighter OTA; and, the Tinsley EQ's saddle is about 5 ft off the ground.  Even so, feels like a work-out!

Edited by Bomber Bob, 18 September 2024 - 08:34 AM.

[Kitfox]

I am keeping the mount pylon for the 12 for one sole reason...that you may sell me that mount one day!!!

[Bomber Bob]

Years ago, I came close to wheeling the 240# Tinsley EQ out to the street for the garbage guys.  Glad I didn't, because after that, I found a local guy who wanted it...  but... he figured-out it was too heavy for his observatory's plywood floor!  So, I did some restore work on it, and rolled it into our living room... this hardwood floor has solid concrete block piers in the crawlspace -- even extra ones because of the real brick fireplace.  Even that wasn't enough support for it.  I cleared-out some mounts & tripods, and made a new spot for it in the shed.  But, we're gonna be leaving The Swamp...

 

When that time comes, I'll shoot you a PM.  Better yet, with my limited short-term memory, shoot me a PM when I start posting about leaving this place...

[Kitfox]

Years ago, I came close to wheeling the 240# Tinsley EQ out to the street for the garbage guys.  Glad I didn't, because after that, I found a local guy who wanted it...  but... he figured-out it was too heavy for his observatory's plywood floor!  So, I did some restore work on it, and rolled it into our living room... this hardwood floor has solid concrete block piers in the crawlspace -- even extra ones because of the real brick fireplace.  Even that wasn't enough support for it.  I cleared-out some mounts & tripods, and made a new spot for it in the shed.  But, we're gonna be leaving The Swamp...

 

When that time comes, I'll shoot you a PM.  Better yet, with my limited short-term memory, shoot me a PM when I start posting about leaving this place...

 

I'll have my eye on you...my observatory has an engineered 5" concrete pad floor.  Should be fine...

[Kitfox]

Question for the group…the focuser on this Tinsley has a 2.75” opening, same as the smaller PlaneWaves. I have gotten into PlaneWave’s odd quote system to buy a 2.75” male to 2” female adaptor to get to standard dimensions.  But I have no idea if or when I will hear back from them.

 

Anyone have any idea what another source would be for this adaptor, or is this going to be a PreciseParts purchase? 

[jragsdale]

Question for the group…the focuser on this Tinsley has a 2.75” opening, same as the smaller PlaneWaves. I have gotten into PlaneWave’s odd quote system to buy a 2.75” male to 2” female adaptor to get to standard dimensions.  But I have no idea if or when I will hear back from them.

 

Anyone have any idea what another source would be for this adaptor, or is this going to be a PreciseParts purchase? 

Is it threaded? What's the size you need?