Worm and wheels in Oz??

[Merlin66 (Ken)]

I'm seriously looking at building a Coelostat when I return....
I think I can now find the necessary front surface mirrors (at a price!!!) but I still need to consider the mirror drives....
A couple of 360:1 worm and wheels, probably 150 to 200mm diameter would do the job.
Are there any known suppliers in Oz??
(or do I rush around at the last minute, as usual!, here in Europe to find some in the next week or so)

[Poita (Peter)]

Have you considered doing a friction drive instead?

As for worms and wheels, in my experience you will have more luck in Europe than here.

How much are the mirrors, I have been contemplating the same project for a long time now.

Are you making a type 3 like the Swedish 1-m jobby? http://www.solarphysics.kva.se/Natur...scope_eng.html

[Merlin66 (Ken)]

Peter,
Yeah...something like that!
The mirrors will be full thickness 6" diameter, so I think the worm/ wheel stepper motor is the way to go.....

[koputai (Jason)]

I know I'm digging up a really old thread here, and Ken, you've probably given up on the
coelostat idea, but:

What about using a normal EQ mount, like EQ6, HEQ5, or whatever, and mounting your
mirror on a linkage that halves the rotation?

You could take the reticle scope cover off as shown in the picture attached, and mount
the mirror on a bearing or bush attached to the end of the polar scope (I've never used
mine, and probably never will) and have a 2:1 linkage that mounts to the top of the pier
or some other convenient spot. The mount could then drive at its normal sidereal rate,
but the 2:1 linkage would halve the rotation of the mirror.

The second attachment shows the general placement. I've not gone in to much investigation
on this as yet. The good thing about this, is that your normal solar scopes can stay tracking
the sun, as shown, and the coelostat mirror can run on the same drive at the same time.

Cheers,
Jason.