Thursday, May 6, 2010
The telescope started out as a two-strut design (the picture shows an early stage with the struts not cut to size). The struts are 1" square poplar, and attach inside the mirror box with carriage bolts and knobs (unfortunately, one has to be careful not to bump the carriage bolts against the primary--space is tight). However, I removed one strut and found that it was basically just as stable with only one, so in the end there was only one.
I then cut the strut in half, with a diagonal cut, so it would easily fit in a small suitcase. Four machine screws hold the halves together, and it is just as solid as if it were a single piece. I used JB Weld (yes, again) to capture the nuts for the machine screws, and to reinforce the thin edges of the wedges. In general, I don't like dealing with nuts flopping around, so I like to JB Weld them.
By the way, I finish wood with a mix of Titebond II and water (about 1:1, but I am not very precise) and when I want to paint it with somewhat glossy paint, I replace some or most or all of the water with DecoArt Crafter's Acrylic paint. So, that's the black paint on the strut. It's a cheap and easy finish. It doesn't look great, but I am all for cheap, easy and functional. And, as a bonus, it's a low VOC paint. Inside the mirror box, I then went over with the acrylic paint again to get a flatter layer.