Progress

 

Page 1

(May 29-Jun 19, 2004)

Page 2

(Jul 3-Jul 23, 2004)

Page 3

(Jul 29-Sep 4, 2004)

Page 4

(Nov 11, 2004-June 23, 2005)

Page 5

(July 28, 2008-present)

 

July 28, 2008.  The observatory continues to be in regular use and has stood the test of time very well.  The shelter has continued to be weather- and windproof, sustaining driving rain, snow, and hurricane force winds without a problem.

But one issue continued to plague the design: varmints!  Being surrounded by fields has its advantages and its disadvantages.  In the latter category are field mice.  They would like nothing better than turn the observatory into a mouse house, and in fact, have been somewhat successful on several occasions.

To better guard against unwanted companions, 1/2"-thick exterior-grade plywood "skirts"  have replaced the flexible rubber mats used in the original design (see the photo taken on September 4, 2004).  The photos here show the modifications.

The skirts along the back side of the shelter fit so tightly to the track (note the cut-out around the track's profile) that they are hinged to swing out of the way prior to rolling the shelter off the telescope.  A small knob added to each panel makes opening easier.  A bungee cord hooked between the knob and a small hook in the shelter frame, not shown, hold the panel open.  Adhesive-backed weather stripping fills the gap between the skirt panel and shelter created by the hinges.

 

Not shown are the two skirts along the sides of the shelter, which are simply screwed permanently in place.

 

The door skirts are held in place by two pairs of thumb knobs, which you see here closed (left) and with one opened (right).  

These could not be hinged as because they would have hit the track whenever the two doors were opened.

 

November 1, 2008.  My neighborhood has recently increased by two houses.  Unfortunately, one of them is on the (formerly) empty lot right next to my observatory.  As a result, localized light pollution is about to go through the roof, once my new neighbors move in.  Although that hasn't happened yet, and while I am sure we can come to an amicable solution regarding their outdoor lighting, the fact is that the house also has several windows that open right onto the observatory.  Therefore, I need to create removable light shields to block their indoor lighting when I am out observing.

To do that, I have made three shields from 1-inch diameter PVC piping from Home Depot and/or Lowes, and tarps from McMaster-Carr, a great hardware supplier. Taking a look at their huge inventory, I found part #87995T41, an 11-mil black/silver tarp measuring 6'x8' under the heading "General Purpose Polyethylene Tarps" about 2/3s of the way down catalog page 2066.  The tarps are affixed to the frames with self-threading screws through each of the reinforced grommets.

The entire shield is attached to the observatory's wall using 3/8-16 thumb knobs, also from McMaster-Carr.  The knobs thread into threaded inserts  installed in the wall's frame.  Fork-shaped hangers (in red) serve as guides for the pipe frame.

When in use, the shields are rotated vertically; when stowed, they are placed horizontally against the wall and held in place using another thumb knob.

So far, so good.  The only problem I foresee is if it is windy.  That could make erecting the shields, or for that matter keeping them in place, difficult.  Time will tell.

 

Below: Reverse side showing PVC frame construction (parts: four 90 elbows, two Tees, and pipe cut to suit).

Above: Panel set up (see the new house at right?)

Below: Shield attached to the wall.  Note the thumb knobs going into the top wall beam and the red hanger on the center wall beam.

Below: Shield in stowed position.

 

 

 

Page 1

(May 29-Jun 19, 2004)

Page 2

(Jul 3-Jul 23, 2004)

Page 3

(Jul 29-Sep 4, 2004)

Page 4

(Nov 11, 2004-June 23, 2005)

Page 5

(July 28, 2008-present)

 

Questions?  Comments?