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5/28/2007 - The Point of No Return!!!! - The Mirror Box is cut to size.

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So after I weighed the completed Secondary Cage, Tailgate/18-Point Flotation Cell, Primary Mirror and completed the focal length test it was time to determine the Mirror Box depth using simple torque equations and a spreadsheet. Although the equations were simple, the amount of "stuff" (like determining that 5/16" Baltic Birch plywood weighs 2 lbs per square foot) that is used in those equations was a little tedious. After all the math I determined that my mirror box would need to be 21.75 inches deep. This depth will allow it to apply the same amount of torque as the truss tube and Secondary Cage on the other end. Combined with the perfect coefficient of friction on the bearing surfaces, this balance is what will make the scope "buttery smooth". Once the mirror box was cut however, I had reached a "point of no return" in the sense that if it's wrong and the scope doesn't balance, it will take $50 of wood and 3 days worth of work to make another one!

ENTRY PICTURES

My brother and I shoot a buoy and lighthouse 3 miles down Narragansett Bay from Latham Park in Barrington, RI. These objects were far enough away to confirm the mirror's focal length of 99.5 inches. Now, where is that lighthouse? Bet my brother wished he had some shoulder straps for that drum. My father (left) and brother looking sophisticated.....uh, yeah. The mirror box has been cut to size (eek!) and the lower front corner rounded. This rounding allows more clearance between the mirror box and rocker box thus allowing for a rocker with very SHORT sides which are more RIGID.

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