Adding a few hardware items can enhance a tripod's utility for an astronomer operating in the field. They can help keep control of telescope eyepieces and other support equipment. The accompanying photos show additions made to the author's tripod for an 11" telescope. The additions make it easy to keep ancillary equipment handy.

Two L-brackets were attached to the upper leg support ring using sheet metal screws. One supports a shelving arrangement (the apron), and the other carries a 12 volt D.C. power supply. The L-brackets were fashioned from standard hardware store products.

Several shelves of 1 x 4 inch pine were attached to a backplane made of a trapezoidal piece of ¼ inch plywood. The shelves were pre-drilled with holes that can accommodate various sizes of eyepieces, hex keys, screwdrivers, extenders, a dew gun, and other ancillaries. A slot at the top of the backplane slips over one of the L-brackets, suspending it against the legs, something like an apron. The slot is reinforced with some hardwood pieces. The apron is stabilized by a ¾ x ¾ inch wood crossbars attached to the rear side, behind each shelf. The crossbars fit between the legs. The shelves and the crossbars are attached with long wood screws, allowing for easy removal and modifications. The slope of the shelves keeps things from rolling off the front of the apron. A wooden block with a curved slot in it extends from the back of the apron. It is located high enough to allow the corrector-plate cover to be hung out-of-the-way during viewing operations. A dew cover for the whole apron was shaped and sewn out of a piece of vinyl upholstering fabric. It attaches to the apron with clothing snaps.

The handle of the 12 volt power supply slides over the second L-bracket. This 12 volt gel-cell supply hangs near the top of the tripod, facilitating power connections. Three extra power output connectors were mounted (with individual fuses) on the power module in parallel with the existing connectors. Thus, each powered application has its own access port, minimizing tangles and adapters.

A plastic pocket on the front of the apron contains a printed card bearing information about the magnifications and field widths obtained with different eyepieces. The wood parts should be coated with some waterproofing material. (Varnish, polyurethane- user’s choice).

The apron concept described and pictured in the attached photos is much handier than the flat circular tripod tables in common use today. Small parts are less likely to be lost by rolling off the table. (Once in the grass- lost forever!). The geometry and dimensions of other tripods will vary, of course. However, the reader can apply the ideas suggested, and with a little imagination he can fashion similar additions adapted to his own tripod. Careful planning of the shelf layouts will assure that there is a place for everything, but the flexibility of the design allows for later changes. More shelves or even a second apron could be added. The apron was featured in an article in Sky and Telescope, March 2000, page 133.

These innovations are dedicated to the St. Petersburg Astronomy Club, as "SPAC Tripod Tooling".
 
 

André S. Medvedeff

August 15, 2002