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I made a dew/light shield out of long sheets of craft foam and stiffened sticky felt. The sticky felt to act like flocking, and I chose the stiffened version to help support the rather large quantity of less than super sturdy foam. The stiffened felt has the nice side effect of being significantly easier to apply than the stretchier standard felt.

I used strong double-sided tape to join the sheets of craft foam together. I needed a few more inches than two sheets would provide, so there are three seams, one of which has the velcro.

To apply the felt I cut it into 4.5″ wide x 9″ long strips (cut the sheet in half lengthwise). I applied a strip of velcro on each end of the shield so as to be able to tighten the shield if necessary and also allow it to fold flat for travel.

With a little rolling up to curve the felt and release the flat tension a little, I now have a nicely round and sturdy light shield for about $7.

You’ll notice the rectangular cutout, that’s for the knob that suddenly became necessary.

Here you see both the main light shield and the miniature one for the finder scope. They’re constructed in relatively the same manner, except for the finder I made used much narrower strips so as to avoid making it too stiff.

I found this knob for next to nothing at Lowe’s. It’s made of ceramic and relatively light weight. I found really nice similarly sized metal knobs, but aside from the cold factor, they were seriously heavy. This knob is threaded for #8 screws.

I attached it using a 3/4″ long #8 screw through one of the holes that holds the ring onto the front of the scope. The metric threading for those screws isn’t quite the same as the #8, but it’s close enough that it can be made to fit with a bit more oomph using the screwdriver. I figured this was a good way of going, it’s in the right place and I didn’t need to drill a new hole in the OTA.

You’ll notice there’s a little gap because the knob is larger than the space available; I took up the gap with a pair of rubber washers, it’s nice and tight now and won’t scratch the finish of the tube. The white ring is a reflective tape I added to the front and back of the tube, helps notice where the scope is better in the dark.

I tried to use the clevis/cotter pin mod, but couldn’t find one long enough to work well with the magic (vs. super) sliders. I found that a 2.5″ hex bolt with a mix of nylon & steel washers, topped off with a lock nut, has been as close to perfect thus far. It’ll keep the ground board from falling off, eliminates wild wobbling, but provides no downward tension to effect azimuth motion. There is probably just a hair more than 1/32″ of an inch spacing, one more 1/16″ washer would fit, but then it’d be tight.

I superglued 3 1/16″ nylon washers together to go between the two bottom “plates” around the center bolt. It sort of acts like a slightly more sophisticated version of either the milk jug washers or the cdrom washers (which I had used before). I’m going to be on the look out for UHMW washers, or something similar that is slightly more slick.