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View Full Version here: : Grand old Dame revealed - planetary paradise or money pit?


Robert_T
22-06-2006, 07:57 PM
Hi All, I promised some pic's of my old home-made 12.5in F6.7 newtonian and custom built EQ mount from eon's ago. This has been collecting dust under my house for near on 15 years now...

The mount is truly massive and was machined by someone I'd call as much an artist as a tradesman (not me obviously) :D. It's shown here with my eq5 pier mount C9.25 in the background. Note especially the twin 16inch brass and aluminium machined drive wheels on Both axis. A close up of the declination shows how a stepper feeds a wormwheel then a larger stainless steel worm that feeds the main drive wheel (WD40 can for scale).

THe OTA is more in my style (you've got to remember I'm the sort of person who makes an observatory dome out of paper mache). Anyway, rough compressed cardboard tubing (2.2m long!!!) painted with mirror mounts made from ply, hacksaw blades and whatever else came to hand. The spring-loaded primary mirror cell surprisingly still seems very smooth for collimating. For that extra quirky touch the back of the mirrorblank was signed by Sir Patrick Moore when he was out in the late 80's.

Anyway, there she be. Crying out for love and begging me to resurrect her. Hmmm an F6.7 newtonian with a miniscule secondary might make quite a nice planetary scope with a little work - now if only I could remember how to do things with my hands :D

cheers,

davidpretorius
22-06-2006, 08:02 PM
this looks like a great project, I thing you will enjoy it very much!!

wow, what a beauty!

Robert_T
22-06-2006, 08:48 PM
I would, of course, have to overcome my chronic laziness... but it'd sure be nice to make it all shiny again:)

asimov
22-06-2006, 09:02 PM
Oh yeah!! I'd love to get my mits on that baby! Not to own, but for the pleasure of just working on telescopes! :thumbsup:

I'm about to strip mine down & repaint it again just for something to do :D

ChrisG
22-06-2006, 09:02 PM
SWEET!!!

That is a goreous setup and yes that would be a planet killer.

Thanks for sharing.

leon
22-06-2006, 09:11 PM
At least the dog wouldn't knock that mount over in the dark, if you don't want to work on it send it to me, i'm looking for another project.

Leon

ballaratdragons
22-06-2006, 09:33 PM
Yeah Robert!!!!

A Man I can relate to. Art from old bits and junk!

Ya gotta do the right thing and restore the old beast into a working masterpiece, shiny brass, polished aluminium and all!!!!

Oooo, it warms my heart. Please keep us up to date with each step of the restoration. Pics would be nice too.

netwolf
22-06-2006, 10:34 PM
wow well i am just wondering how you polar align that beast. It looks loked in to a particular lat to me. Shure are beautiful and its definetly worth the time restoring them.

Regards

Robert_T
23-06-2006, 03:50 AM
Hey wolfy, it is setupfor SE QLD latitude, but it does have some sizable stainless threaded rod that allows for adjustment in the range ~25-32deg lat. It has around 5 deg of long adjustment possible in much the same way once the base is bolted down:)

Robert_T
23-06-2006, 03:59 AM
Thanks Guys,

Don't worry Ken, if I do anything to the beast I'll be plastering it in here too ;)

And Leon, reckon you're right, it's pretty stable. Most of the mount is made for 1inch plate steel:eyepop: I don't know the weight, but I couldn't even shift it a centimeter by myself to take these photos. From memory I had 3 helpers to carry it when I "rescued" it from the old observatory.

cheers,

[1ponders]
23-06-2006, 08:10 AM
:lol: That is awesome Robert. :lol: What a fantastic looking mount. IF you are not going to do anything with it, I'll put in the first bid. You could tie the Titanic up to that thing. And you're right, it really is a work of art. :)

iceman
23-06-2006, 08:23 AM
Wow what a beast!

You gotta get that thing working again. I reckon if you put a call out for helpers in SEQLD you'd get some willing bodies to help bring her back to life.

That would be a planet killer.

sheeny
23-06-2006, 11:33 AM
That's quite impressive Robert!

But not as impressive as this:


Man! I am just imagining the head spins from blowing up the balloon!:rofl:

Al.

ving
23-06-2006, 12:48 PM
if you ever decide you dont wantit.... ;)

thats quite a beast robert! :)

Robert_T
23-06-2006, 12:50 PM
you should of heard it when I popped it at the end:D

[1ponders]
23-06-2006, 01:17 PM
Rob, how old is the mount and scope? If it's old enough you might be able to apply for a heritage grant from the gov to do it up :evil:

Robert_T
23-06-2006, 01:33 PM
I like your thinking... but despite the obvious historical significance of the Cabbage Tree Creek observatory it ain't THAT old:D

asimov
23-06-2006, 03:10 PM
I'm interested in a close up shot of the DEC shaft Robert. From what I can make out in the photograph, the counter weights are not attached to the DEC shaft at all. Is this correct or am I seeing things?

Robert_T
23-06-2006, 03:22 PM
what sharp eyes you have their Asi-meister. you are correct, the declination shaft (2inch solid mild steel) runs beween two large bearings which are fixed to plate which has the counterweights attached. Don't ask me why, but there was a reason at the time:shrug:

asimov
23-06-2006, 03:46 PM
Yep. It's so when you move it in DEC the counter weights don't turn as well. It eliminates the potential out of balance issues sometimes encountered if for example the weight/DEC shaft is slightly bent or the counter weights are slightly off centre in relation to the shaft. Brilliant yet simple. My compliments to the craftsman that designed & built it.