The truss assembly

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The secondary cage and the mirrorbox are kept at the right distance from each other by means of the truss assembly. I have studied many solutions to attach the trusses to the secondary cage and mirrorbox and I have choosen to go for Kurt Maurers system, as shown in the picture. The trusses are made of 1.2 inch outside diameter, 0.059 inch wall thickness aluminium tubing, just like the struts of the secondary cage. They are, at both ends, attached to each other with 1.2 inch wide, 0.12 inch thickness aluminium angle. This aluminium angle also has the function to attach the truss assembly to the mirrorbox and the secondary cage. To attach the truss assembly to the secondary cage, I copied Kurt's system, as shown in this picture. The bolts on top of the aluminium angle are attached to the lower ring of the secondary cage with wingnuts.

To attach the truss assembly to the mirrorbox I used a variation on Kurt's system. The trusses are bolted to the aluminium angle. The aluminium angle is fastened in the corners of the mirrorbox with a big knob. The blocks pressing the angle in the corners a skewed off, pressing the the aluminium angle firmly against the walls of the mirrorbox. In these four pictures is shown how things are done.

The system works perfect! It takes no longer then 10 minutes to assemble the telescope and a bit less to disassemble. If I work accurately, I do hardly (if at all) need to recollimate the telescope after setting it up.

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Email: Jan vanGastel