Secondary mirror cage
I didn’t deviate much from the classical Kriege design (see Dave Kriege en Richard Berry: “The Dobsonian Telescope”). I still like two rings better than a single one. With a single ring the secondary mirror is always very exposed and vulnerable. Also, with a heavy secondary mirror (>500 grams), a Feathertouch focuser and heavy eyepieces (Televue, plus Paracorr), a single ring is not sturdy enough in my opinion. In addition, with two rings, the secondary mirror is protected. And when kept together with four small trusses and Kydex, the cage is extremely rigid. The focuser is equipped with a Moonlite filter slide to change filters. The secondary mirror is heated by a devise from Astrosystems, driven by a 12 volt battery. The spider is from Astrosystems too.

Trusses
I use an eight, not a six-truss system, for once because an eight-truss system is most effective to support a light shroud. This I consider important for three reasons. First, as the name says, it keeps light out, which is crucial in my hometown Amersfoort, a heavily light-polluted city. Secondly, it protects against circulating warmed air in the lightpath that is produced by body heat. Finally, it catches a lot of humidity that instead would be everywhere else in the telescope and optics.

All eight trusses are at both ends connected to each other to keep them together. How they are connected at the tops end I copied from Jan van Gastel (Jan van Gastel's ATM pages). In short, the ends are attached to each other with an aluminum angle. A bolt through this angle goes through the lower ring of the secondary cage. This bolt (and the trusses) is then secured with ebonite knobs (see an example in the picture above). The advantage of this system is that the secondary cage/ truss assembly is very easy to break down, and that it is also very rigid.

At the bottom end, two trusses are held together by screwing them to another(below, left), small truss that slips in a hard wooden profile. This profile can be opened (below, middle) and closed (below, right) with a quick-release fastener that is used to support bicycle seats. Also this attachment is very simple and effective. The fasteners are located underneath a thin wooden frame that is painted black underneath (to prevent stray light). This wooden frame is attached to the mirror box with four, easy to remove large ebony knobs.

So I have the secondary cage, the trusses and the wooden frame together as one piece, which I can remove from the mirror box within half a minute. I just store this assembly as one part in the garage. Now I can assemble and disassemble the telescope very quickly in three easy to handle large parts: the above described secondary cage/truss/frame combination, the mirror box and the rocker box.

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