Update: May 20, 2012
The official Telescope & Sky (that was the original name
of my website) observatory is complete! First light for the entire
setup was May 19, 2012. An alignment of the equatorial was performed,
and then a GoTo alignment was done. The result was pretty good,
but it's been better. I will need to take time to do a really precise
alignment of both. It was a clear night in Erie, with a few high,
wispy clouds. There was a lot of atmospheric unsteadiness, so image
quality varied considerably. The JMI electric focuser is extremely
nice; not having to touch the telescope during focusing makes a
world of difference in how well the NexImage camera can be focused,
especially under conditions where the image is being randomly distorted
by the unsteady air. Maneuvering inside the shed is a bit tricky,
but it is possible to get a comfortable viewing position for everything
so far - with some position more comfortable than others. Total
investment including telescope, building, and accessories (not including
computer) is around $2,500 - it ain't cheap, and that is with fairly
low-end equipment and buying used (eBay) where possible.
In the picture (below) of the observatory, you will see a piece
of plastic about 9" down from the top of the pier. I needed to pour
an extension to clear the top of the shed enough to have a good
view to the east. The plastic is a separator so that it is
removable in case I get a new mount or
new telescope someday and need a different overall pier height.
1/4-20 all-thread bolts run from the original base, up through paper
tubes, so that the entire extension can be lifted off. It took exactly
one 80-lb bag of concrete to fill the 12"-diameter form.

Official Telescope &
Sky Observatory First Light on May 19, 2012
Voila! Here is the completed Telescope & Sky Observatory.
Total investment: ~$2,500.
After a year of using my Celestron 8SE telescope on its tripod,
and in alt-az mode, I decided it was time to commit to a location
in my back yard and build an observatory. My yard sits on a unobstructed
north-facing ridge in Erie, Pennsylvania, which looks directly over
Lake Erie and into Canada. Although there is a fair amount of city
lighting to the north
(I'm about 2 miles from the lake) and especially to the east,
the southern and westerns skies are not too bad
(for a city, that is). I bought a used Celestron equatorial wedge
- the heavy duty one made for the C-11- and I bought a used JMI
electric focuser on eBay
(both excellent condition, saved ~$250 over buying new).
I was planning to design and build a minimally-sized observatory
structure with a rolling top, and then Melanie handed me a sales
flyer from Sears that had this Rubbermaid® Resin Slide Lid Shed
on sale. It seemed like it might fit my needs exactly. The dimensions
even seemed to be perfect for the height of the pier that I had
just poured. A search on the Internet showed that I was not the
first to decide to convert one of these slide lid sheds into an
observatory. Among the nice features are an integral floor to keep
it dry inside, the resin construction is strong and UV resistant,
it goes together very easily in a short time, and it is not that
much more expensive than building a decent one from scratch. I have
built a lot of sheds and other structures in my lifetime, so being
able to take the easy way out on this one is a welcome change from
the cutting, screwing, nailing, priming, and painting.
As
of this writing I have not had a clear night to do the precision
alignment on the equatorial wedge - it's supposed to be clear tonight,
though. After that, the next order of business will be creating
an organized "office" space to provide a table and low-level light
source for setting up the computer and notebook, plus a storage
area for the accessories. The OTA (optical tube assembly) will be
stored in the house, but everything else will remain in the observatory
These construction photos are posted in reverse chronological
order. To start at the beginning, please go to the
bottom of the page and work you way back
up.
If you are interested in seeing the guts of a
Celestron NexStar 8SE, please read my teardown report on it.
I also did a teardown report on the Celestron
NexImage telescope camera.


Removable 9"-High Extension
1-mil plastic sheet was placed on top of original pier in order
to make the extension removable. Three layers of notebook paper
were wrapped around a 1/2" wooden dowel to form tubes to place around
the 1/4-20 all-thread bolt extensions to allow concrete extension
to be lifted off if necessary. A 1/4" plywood template was made
to locate the tops of the mounting bolts for the equatorial wedge.
The 12"-diameter Quik-Tube form was a snug fit over the original
pier, which is what is desired. Duct tape held the tube in place
after using a straight edge to ensure that the tube was parallel
to the original pier. An 80-pound bag of Quikrete fills 0.6 ft3.
The Volume of a 12" diameter cylinder, 9" high is about 0.59 ft3.
The single bag just barely filled the mold (actually about 1/8"
low), so Quikrete is over-stating its capacity, especially since
subtracting the Volume of the three bolt clearance tube makes the
actual Volume even less.


Rubbermaid Slide-Lid Shed Assembly - Door installation
and completed shed!
Total assembly time: Around 3 hours
The final step was installing the two doors. A bar on the sliding
roof with a hole in it for a lock pokes through a slot in the overlapping
doors. I don't store the telescope or eyepieces outside, so there's
nothing for a thief to gain after breaking in. The west side of
Erie is a very safe area (the welfare crowd is on the east side)
so I'm not too worried anyway.


Rubbermaid Slide-Lid Shed Assembly - Sliding
roof section assembly and installation


Rubbermaid Slide-Lid Shed Assembly - Wall and
fixed roof section assembly


Rubbermaid Slide-Lid Shed Assembly - concrete
pad preparation and floor assembly
A clearance hole was cut in the floor panel to make way for the
12" pier. Concrete screws were used to secure the floor to the pad.


Wooden frame for concrete pad w/rebar framework
(3½" min to 5½" max).
The pier was wrapped in 4 layers of corrugated cardboard for isolation
from concrete pad. After the concrete hardened, the cardboard was
removed and sidewalk crack caulking was applied between the pad
and the pier. 120 vac weatherproof GFIC receptacle box was installed
along with an underground feeder inside 1/2" PVC pipe.

12" diameter Quik-Tube for for the pier post
(note rebar inside)

Concrete poured.


Digging the pit for the pier footer post.
A 24" wide square hole was dug 32" deep for the concrete pier
footer and column. 3/8" rebar was bent and wired to ensure maximum
strength and resistance from cracking due to the ground freezing
and thawing.
Posted April 21, 2012
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