Astrozap Truss Dobsonian Shroud and Soft Cover

My 16″ Zhumell reflector required a specialized shroud. It has three struts rather than the typical 8-truss structure. The lack of trusses means that normal light shrouds would dip into the light path when the telescope is pointed at anything other than zenith. As Light Bridge reflectors are very similar to Zhumells, I ordered the Astrozap shroud for a 16″ Light Bridge telescope from Scopestuff.com. Scopestuff is nearby and have been reliable with fast service. I also threw in an order for a soft cover to fit over the secondary cage. The costs were $89 and $21 respectively.

Within a few days, both arrived via Priority Mail and were in individual plastic bags.
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They were made of an opaque cotton and nylon blend black cloth. The dust cover had an elasticated edge to snugly fit over the secondary cage. The shroud had drawstrings at both ends to keep it in place as well as two stiffening bands to keep the shroud from sagging into the light path. Also included were instructions.
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Shroud assembly couldn’t have been more straight forward. I removed the secondary cage and slipped the shroud over the three struts and then reassembled the scope.

I pulled the shroud up and over the strut bolts at both ends and tightened the drawstrings. The dust cover was secured in place.

After several uses, I’ve determined that the design could be improved by adding a third stiffening band in the center of the shroud (labelled “A”). Although the sagging was minimal, it could have been prevented with the extra band. If I were to attach two lightweight bungee straps (one on either outer side) to the bottom of the shroud and telescope, it would pull the shroud taut to eliminate the sagging (labelled “B”). During periods of wind while observing, the upper drawstring is loosened to slip the shroud to the base of the struts.

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Overall, I’m very pleased with my Astrozap shroud, and it works very well for the three-strut design. The only improvement I would like to see is the addition of a third stiffening band.

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~ by Erika Rix on June 15, 2013.

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