Ad Astra Observatory

Trixie definitely needs to be rebuilt. The 3-strut system is not working.

So I am going to rebuild and try to fix two main problems.
1) flexure — replace strings with struts
2) balance — move the mounting plate forward

In order to keep the labor to a minimum, I am going to try to salvage as much of the scope as possible. So, I am going to reuse the rings, and cut the current tubes to fit the new design.

One thing that I have discovered while trying to work up the new design is that it’s easier to do a 6-truss design if you have the triangular rings set opposing each other.

Here are 3 mockups of the design, demonstrating what I mean:

and a Google SketchUp of the same:

To move the mounting plate forward, I will need to add a fourth ring, so some cutting will be involved (and I may decide to redo the rings entirely, although that seems unlikely).

So I will have 3 sets of struts (for the UTA, for the mounting area, for the mirror box). If I use Moonlite connectors for those, that’s 18 sets of the two-ball-and-socket adapters, $27ea, call it $500 with shipping. More like $375 if I can pull off a dealer discount.

I can get most of the raw material for the needed struts from the current struts and the leftovers I have lying around, but I will probably need another pole or two.

Knowing now what I didn’t know then, I should be able to get this done in 2 weekends. One weekend to cut and varnish the new ring, and one weekend to install all the new hardware.

I’d like to see Trixie go into operation at some point. The new design still leaves open the option of conversion to a Dob mount.