20"Obsession + Argo Navis + Servo Cat = GOTO BLISS !!!!

I'd officially like to congratulate Dave for buying me...er..I..mean..
for buying himself the Argo Navis and servo Cat!


Lads,
This thing is awesome.
The ultimate scope!

I am so totally buying the same.
(maybe even a few inches more )

Many happy years observing with it Dave!

Wow, Dave, she's lookin' good! Can't wait to see it (again) in person!

In a fit of uncharacteristic enthusiasm (i.e. if I don't do it now, I never will!) I stripped down my field de-rotator and gave it the old Page 3 treatment (expose everything!) Hope the photos are clear enough to give you an idea of what is involved:


Above: Field de-rotator installed in new top-cage


Above: Inside the field de-rotator with the back removed


Above: Close-up of the Oldham coupling


Above: Worm Drive with rotating hub


Above: Worm drive shaft, with rotating hub removed


Above: Bearing support pillar


Above: DIY Nylon gear on rotating hub (blurred!)
The worm drive is just a short length of M6 stainless steel threaded rod driving the main gear on the circumfrence of the centre hub. This gear is made simply by trapping two lengths of Nylon M6 threaded rod in grooves cut into the inner faces of the hub. The threads mesh together to form a remarkably good gear.

You can see larger versions of these photos at: www.flickr.com/photos/7362801@N08/

Phil.

Phil,
Thanks for the explaination and pics on the de-rotator.
I have about a million things to get done before I could venture into doing that.

Just as an update, we went up to the hill on Friday night and boy was it cold especially when the wind blew.
I did the 2 star alignment procedure (including the mount zenith reference) and the gotos worked bang on the money, most times it placed the object fairly center of the 26mm eyepiece and tracked the objects pretty well.
I'm going to make up a laptop holder for the scope, its just a pain having it on a separate table.
This guy is charging 265$ for his,
www.marklessastronomics.com/#podium
that is alot for it really, anyone know where I can get this multi multi layer baltic birch wood or something equivalent?, I'll make this myself for a fraction of the cost.

The dew heater in the Argo Navis kept the screen and most of the controller dew free while everything else get dewed and in some placed it froze solid, it was that cold.

anyone know where I can get this multi multi layer baltic birch wood or something equivalent?, I'll make this myself for a fraction of the cost.

Yip.
If you give me drawings of exactly what you need I can get
whatever you want cut out in oak, walnut or cherry.
Cherry would be the best choice there as it's the hardest.
Looks wise it's very close to the finish on the Obsession.

Email me plans and I'll get you a price.
(may be for nothing as the company I order this kind of
timber from owe me a favor or two!
)

Hi Dave,

What can I say fantastic. May you have all the luck with your new toy. Frank may you be even happier using Dave's Scope I'm looking forward to seeing some deep sky objects from you two Well done.

Will you be bring the scope to Galway? I might bring my camera,s