10 inch Travelscope

[Rod]

I have been working on this 10 inch Travelscope to take on a 6 week holiday to the Northern Territory. The mirrror is home made - plate glass F6 and used to live in a heavy cardboard tube and plywood mount.

This design is based on Greg Babcock's 12 inch described here:

http://synrgistic.com/astro/telescopes/traveler.htm

I used Albert Highe's idea of a connecting ring so the poles could be halved in size.

The scope is nearly finished. I used it last night for the first time and was generally happy with it. It is very light and easy to set up and take down. In use I add a sheet of plastic to the upper ring for baffling.

I need to add some detachable legs to the ground board as it tips occasionally due to the small footing.

I had a lot of help with this. Bruceaust CNC routed the plywood for me. Members of the Instrument Making section of the ASV offered lots of suggestions and Ken Beard (section director) tidied up the poles on his lathe for me so they fit together better.

We leave next Saturday so will need to have everything completed by then. Any suggestions for improvement though are very welcome.

Rod.

[mercedes_sl1970]

Wow - what a terrific scope.

Curious to know how much it weighs. And, how do you find the stiffness of the polls re upper cage movement.

Andrew

[Rod]

Thanks Andrew,

I don't know the actual weight. I just pulled it down to epoxy in a few loose inserts. I'll weigh it next time I re-assemble it. I can easily carry it with one arm. The poles are surprisingly stiff. I think the connecting ring in the middle adds some stiffness. The upper ring is very stiff when attached at the top. There are recesses for each pole to fit into. The upper ring is quite flimsy when it is detached from the scope.

After building this and a 6 tube truss (for a 12 inch) I would seriously consider a 3 pole design for any moderate sized scope. I can't see any loss in rigidity and the design becomes so much simpler.

Rod.

[mercedes_sl1970]

Rod

Thanks for the info. I'll keep your design in mind if I build another scope...

Andrew

[Rod]

For Andrew and anyone else interested the scope weighs 12kg.

Attached is a photo of the carry on section. Inside is the main mirror secondary cage and connecting ring. The ground board is the lid and the case itself is the mirror box. Altitude fins, rocker and truss tubes go with my luggage. The truss tubes break in half for storage. I leave tomorrow. If there is any interest, I'll give a report on its performance.

Rod.

[Bruceaust]

The scope looks great Rod.
I hope it performs well.

Bruce