Smaller telescopes tend to use tubes and larger telescopes trusses - we shall look at each in turn. The truss is a triangle, the triangle is inherently rigid and the result is completely stable optical tube assembly -- but with all the benefits of the ultra-lite design. Example is the telescope tube: optics on both ends held with cylinder; cut away portions of the cylinder keeping only those portions that transmit load, leaving a truss or bay pattern. Telescopes: Truss Telescopes: Ultra-Light Conversions: Scopes and Testimonials: Parts and kits: Components for the ATM: The "ETT" (Easy Transport Telescope) Telescopes for sale: Links: Contact Us: Pricing: Payments Paypal and Credit Cards . We've got the perfect solution - Orion's SkyQuest XX12i IntelliScope Truss Tube Dobsonian Telescope. The tube or trusses of a telescope must perform the task of holding the optical components at the correct separation and at the correct relative alignment, regardless of the orientation of the telescope on the sky. Complete Telescopes Now Available! A large single cylinder can be replaced with numbers of smaller cylinders. One of his recent project is a 10.5 inches F2.7 dobsonian telescope. The trusses are also designed to flex equally, keeping the optics in collimation regardless of the position of the telescope. tubes Integrating the truss mounting holes in the wooden mirror box corners permits Meade 12" LightBridge Truss-Tube Dobsonian Telescope - 1205-05-02 . It really is a very good source of information and advice for anyone building fast telescopes. Shifts in focus due to temperature changes are minimized because of this design. Orion SkyQuest XX12i IntelliScope Truss-Tube Dob If the idea of a big-aperture telescope appeals to you, but the portability issue has kept you on the fence, you can hop off it now. I really liked the hexagonal design of the tube and I started to look for other geometric wooden telescope. Homemade 12.5 Inch Dobsonian Telescope: How to build a 12.5 inch closed tube Dobsonian telescope. Truss tube placement and truss connector styles are very difficult choices. Kriege & Berry like the trusses mounted on the outside of the mirror box for added stability, but that interferes with clean lines and design possibilities. Lightbridge (or any dobsonian rockerbox) upgrades: Click here for info. This Instructable describe the planning, design, and par… Carbon Fiber Truss Tube Design: Lightweight yet strong carbon fiber truss tubes have low thermal expansion characteristics. In this design, Jon uses 1/4" threaded rod, a "eye bolt" in the top of the mirror box and a turn buckle. I began building it in the spring of 2008, but the bulk of the work was done in July of 2008 with first light occurring on July 25.