Telescope Conversion from Tube to Split to Truss

I wanted to start a new thread about this, as I could make my prior thread go on forever, but it is really finished.

I am considering converting my 12.5 dob to either a Truss or a Split tube design. My main goal is portability to be able to take it to the NC mountains, at my in-laws house, where seeing is incredible!

I was originally thinking Truss, but then I saw how easy to convert to a Split tube it was, and so I changed my mind.

Now Jon ( http://www.astromart.com/forums/viewpost.asp?forum_post_id=675797 ) has got me thinking Truss again, so that may be the "end goal" with a Split tube in the short term (since I can do that in a matter of hours) for using on trips.

I am a "builder" so the idea of the Truss sounds fun. Whats the most difficult part in this design, would you say? Would it be the just the precise cutting of the circles, or something else?

Thanks!

I'm a little bit ahead of you, having converted my 14" solid tube to a split and then later to a truss. Each design has its advantages. The split tube is easy to build and very fast to assemble. The truss is ultra-compact and light weight. The light weight is an advantage not only for transport, but also has a nicer "feel" when pushing the tube and doesn't cause as much vibration in the mount.

One important advantage of a solid tube is that it tends to keep the secondary mirror free of dew/frost. I never had problems with my secondary dewing over with a solid tube, but have had considerable problems with the open truss (maybe I need to use a shroud).

In summary I would say that if the size and weight are not a problem, then go with a split tube; otherwise consider a truss.

I think the most difficult part of the design is getting the balance right. There are procedures published to let you get the work down step by step and end up with a smootly working assembly.

dan