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The history of Oak Hills Observatory is a short one and the enjoyment I get out of CCD Imaging and Star Gazing is well worth the efforts I have put into this project. I began my journey in the year 2000 with the purchase of a 3” dobsonian which was just the teaser. There was no GoTo feature for the scope and although I have always enjoyed the stars I have always been lacking in the science.  I soon learned that I needed a goto scope to satisfy my lack of the science and love for star gazing. Within a few months I purchased my second scope, a  5” dobsonian with full goto features, I was now a happy camper viewing all the wonders provided by our universe. It did not take long for the visual aspect of viewing the sky with a 5” dobsonian to becoming boring to me and I needed more. With my five inch dobsonian I could see things that I had never seen with my own eyes before but I had visions of color and clarity which neither of the dobsonian scopes provided. In May of 2002 I purchased a Meade 10” LX200GPS f/10 which has given me more of what I want in a scope and for now it will have to sustain me. I have been infected with a very expensive illness more commonly know as “Aperturedeliritas” I just can’t seem to be satisfied with what I can afford. It will take some time before there is a cure but I am sure, eventually, I will have my dream scope, which at this point is anything 20” or larger, but that is part of the illness, those who are infected cannot be satisfied with the normality’s of life.

 

 

The following are pictures and processes that went into building my roll off roof Observatory.

I first began my mission with the Meade while it was mounted on the tripod, that came with the scope, and after buying many things that I didn’t need I did find the real need for a wedge.

 

Here is my LX200GPS 10” f/10 mounted on a modified traffic signal pole. The pole was acquired through my previous contacts in the traffic signal industry and it was graciously given to me with the ½” metal plate welded on top to accept the wedge mount.

 

  

Since then I have built a roll off roof shed that I can now call an Observatory…

  

This is the first step in providing my equipment a safe and comforting home.

I laid out 20 1' x 1' concrete pavers for the footing of the shed. I placed the pavers around the perimeter where the shed is going to be and I leveled each paver and from one paver to another all the way around to make sure that the shed would be level.

 
After setting the pavers I began setting down the lumber for the flooring. I made sure the lay-out was exactly 8’ by 12’ from edge to edge to allow for the 4’ x 8’ x ¾” floor sheeting I am using. I then placed 2 x 4 joists spaced 12” on center for stability and strength of the flooring. If you notice I also framed around the base of the pier for easy access to the bolts holding the pier down and also to secure the floor sheeting around the area without touching the pier.

 

I added more pavers to the center field of the flooring structure area to help keep the floor from bowing in the center of the floor. I then began sheeting the floor with ¾” floor sheeting. Using the sheeting as a guide to make things square I started nailing of the flooring and again after making sure the sub framing was square with the sheeting.  The sheeting is nailed off to the flooring frame with an 8d nail every 4 to 6 inches apart. I cut out a square area around the pier and will use the cutouts for final covers with the shed is done.

 

The walls were probably the easiest part of the construction. The walls are pretty much a straight forward design with 16” on center spacing for the studs. I determined the height of the shed walls by pointing the scope in all directions and determining what height would be best for the area around the shed. To the South is the house and the peak of the roof of the house was about the highest obstacle to clear. I determined that 75” was the maximum high needed for the walls to make sure that shed walls were not more of an obstacle then the roof of the house.

 

 

After the walls and the door were built it was time to start sheeting the outside of the shed. I used a pressed wood composite sheeting that was already primer painted on one side, the siding resembles what is considered T-111 siding which is normally a ¾” plywood sheeting but the standard T-111 would have been too heavy for my construction needs. The walls are not nailed together they are screwed together at the corners and screwed to the floor. I built this shed as a temporary Observatory so I needed to make sure it can be disassembled later and moved to another location.

 

The sheeting has what they call ship-lap edges, which allows you to over lap the edges and because of these edges the paneling goes on with an almost un-noticeable seam. The sheets needed to be cut down from the original 8’ heights to fit the actual height of the shed and I kept the trimmed off pieces for later trim out which will be explained later. I used a full sheet of paneling for around the door area  and I cut out the center of the panel to accomedate the size of the door and then the sheet was placed on the wall. The door was made from a 2 x 4 frame and the cutout from the panel was used to skin the door. I used 1 x 3 pine for the border trim around the door. The hinges and hasp were added to make sure the door would work before continuing the sheeting.

  

The paneling/siding went on fairly easily. I started nailing the paneling on with a nail gun using 8d nails and realized that the nail heads were too large for my liking.  The first sheet of siding has 16 of those ugly 8d nails driven into it, I will have to patch and paint 8 of the nail heads to cover my mistake. I continued nailing off the paneling with a brad nailer which shoots a thin 1” long nail and the resulting holes are not seen as easily. I spaced the brad nails about every 4”. I know that most people do not have an air compressor and nail guns available to them but the same thing can be done by hand with a good old fashioned hammer,  I am lazy and like doing things the easy way.

 

Here is a picture of the shed with the door open with the scope, mount, and pier safer than they have been in over a year. You can see the cutouts on the floor next to the pier which I will use later for the future covers for the pier bottom.

 

Here are the (2) 24’ long 1 x 2  ($120.00) channels that I use for the rollers. I have drilled them and counter sunk the holes for the screws that will hold the rails to the top of the shed walls. The rails will be placed from one end of the shed and over hang the other side by 12’ to hold the roof while it is open.

 

 

 

 Here are two photos of the prototype rollers and rail that I used on the shed. This was the first prototype and the rollers cost about $100 for a set of 25. This was not the rollers that I used in the final product but the concept is there. The rollers fit very well within the walls of the channel but there were other concerns that caused me to change these rollers out for another type. I placed the rails as close as possible to the outside edge on the upper shed walls so that the final trim will be easier to install and make the shed walls look normal from the outside. I originally used ten rollers on each side and it all seemed to work quite well.

 

 

At the ends of the rails I installed stops so that the roof cannot roll past the end of the rails. I drilled ½” holes then placed a ½”  bolt with a ½” galvanized pipe as a sleeve, I also used a washer and lock washer then covered the bolt and pipe with foam pipe insulation, the stops are strong and sturdy and will more than easily work to stop the roof from rolling off the ends of the rails.

 

 

  

A 22.5 degree angle was cut at the top end of each of the trusses then the ends were screwed together and nailed with a block to help maintain the angle and to give the truss some stability. The truss tails were left long so that they can be trim cut to the proper length when the fascia is ready to be placed on the front and back edge of the roof.

 

The roof was constructed of 2 x 3 lumber instead of the traditional 2 x 4 for the sole purpose of eliminating weight, but then I put the trusses at 16” centers instead of 24” and gained the weight I save by the lumber size. These are some of the trusses that I built from the 2 x 3 lumber.

  

Here is a view of the framed roof with the trusses in place. The 1 x 2 metal rails are screwed to the shed walls and temporarily supported at the open end to test the roof roll. The lower roof frame is made of  two (12’ x  2” x  4”) lumber nailed one on top of another, one set for each side. I spaced (4) (2” x  4’ x  8’) studs from one end of the roof to the other for lateral support and started putting the trusses in place.   After careful measuring and aligning of each truss to make sure that the overhang was the same on both front and back they were nailed into place and a block was nailed between each truss and to the top of the shed walls. At this point the rollers are working beautifully, the roof rolls from one end to the other when pushed by hand.

 

The eve for the two ends of the roof were constructed using 2 x 3 stock they were notched into the last truss and nailed to the next truss back for support. This gives strength to the over hanging eve so that the weight of the roofing material can be supported.

 

Here are two pictures showing the notching for the eve overhang. These are samples of the cuts and how they fit together.

 

Now the tails of the trusses were cut in preparation of the fascia. Each truss was marked by using a chalk line or string. The string is tied off at one end of the shed on the overhanging truss and then the other end is measured the same distance from the shed walls and the line is marked. After making sure the line is straight and marked I started marking the cut line diagonally across the side of each of the trusses with a square . The cuts were made and the resulting tails were all cut with the same angle and at the same length.

 

The fascia goes on next. While there are a couple 45 degree cuts involved in getting the ends of the fascia boards to match it is quite easy to do. Put the fascia in place by tack nailing the board, with one board in place and making sure it is long enough to reach across the extended eve overhang, place the next board in place and mark where they intersect. That is where you will cut the 45 degree angle. It may take a couple of tries to get it right so you may need to practice on some scrap lumber till you are sure you understand how the cuts will align.

  

After the fascia is in place the roof sheeting goes on. I used ½” plywood sheeting. Line up the edge of the sheeting with one corner of where the fascia meets at one end of the shed and keep it in line and straight, (with either the front and side or the back and side) you need to keep the two edges straight and inline while nailing off the sheeting. In this photo I started on the other end of both sides and the remaining plywood is left overhanging until I have all of the sheeting on the roof and nailed off. Make sure you nail off the sheeting as you go.

 

When you do the roof sheeting it is important not to put the joints of the sheeting on the same truss as you work your way up to the peak of the roof. With this picture as reference I started the next row of sheeting from this end so the joints of the next layer of sheeting would not line up on the same truss. You also will be putting metal trim around the edges of the roof. It is a thin angled metal that will be nailed along the edge of the overhanging eve and touch the fascia. It is a barrier between the roofing material and the wood structure of the roof. 

 

 

 

 

After the trusses, fascia, roof sheeting I put the roofing material on. Roofing is a boring and hot process, especially if the sun is out and the temperature is climbing. The first thing to do is lay the some thick felt paper on the roof and nail it off to hold it in place. I used a special nail that comes with a plastic ring to help seal the paper after the nail has punched through it. It is also a good idea to get the nails in just the right length so that it does not protrude too far into the shed. I used ¾” nails and placed them in line with the trusses so they cannot be seen from inside the shed. 

 

I did not take pictures while the roof was being installed, it was too hot and I did not want to have to climb up and down the ladder to get the camera once I started. But the installation is pretty much straight forward.

 

The first thing you have to do is lay out a line of shingles/tiles all the way around the edge with the tabs pointing to the top or away from the edge of the roof. This first layer ensures the edges are completely covered by the material. I leave about ¼” overhang all the way around to make sure that the rain drips off the tile and onto the metal trim and does not find its way under the tile.

 

There are lines on the felt paper that you first laid on the roof and there are lines on the roofing material, I used composition shingles and they are pre-notched for alignment. For the most part you just have to start at the lower corner of the roof and start placing the shingles down and if you have never done this before try laying out a few rows and see how they line up, check your house roof and see how they did it. Again, the nails are important, I used ½” roofing nails for the tiles, they are long enough to hold the tiles but not too long that they can be seen from inside the shed, I also tried to make sure to nail into the trusses.

 

After the roof was on and prior to trimming out the shed I attempted to roll the roof from one end to the other and to my surprise the rollers were binding. The entire shed roof was stuck. I tried grease on the rails, I tried grease on the rollers and I even jacked up the roof and doubled up on the rollers ( 20 on each side ) thinking that the more the better but nothing seemed to help. Since I was able to jack the roof up to add additional rollers it was not much harder to replace them. I went down to our local Harbor Freight store picked up 25  2” rubber wheels for about $22.00, I put ten on each side and have five for spares . They were a lot cheaper than the rollers I used at first and they worked a lot better. If I had been able to find the kind of wheels with ball or needle bearings I am sure the roof would roll by itself.

 

 

 

Here is a picture of the new wheels that were installed after the roof was completed. Just on the other side of the wheels is the back side of the panels (from the scrap) that was placed to cover the outside lower part of the roof assembly.

It was not too difficult to change out the rollers, I just jacked up the roof by placing a board across the lower part of three of the trusses and used a floor jack to get the entire roof up high enough to take off the other rollers and install the the wheels.

The roof rolls off with some effort now and I can see where it would benefit having it motorized, like I said I am too lazy to be pushing it off and on by hand.

 

 The shed here is almost complete. I have trimmed all around the edges with 1 x 3 pine and made sure all the trim was screwed to the shed so that it can later be removed and the shed dismantled when the time comes. I have added the sheeting to the roof ends and sides and trimmed them also with weather proof strips. I also removed the temporary supports at the end of the rails and installed 4 x 4 posts. The posts are set into the ground with concrete, these are temporary so there is only enough concrete to make them secure.

 

The upper image shows the end caps and trim, the horizontal 1 x 3 moves out with the roof and when closed it looks as one solid wall.

 

The middle image shows the brass and rubber weather stripping, that's the point where this end of the shed meets the roof.. I had to make this end of the shed roof higher to clear the scope while in the park mode. I lost about 6" at this end because I wanted to make sure there was more than enough clearance for the roof to miss the scope. I now wish I would have not raised it because I now have over 7" of clearance.

 

The lower image shows the trimmed out front of the shed. The horizontal 1 x 3 is nailed to the shed and the sheeting above it is nailed to the roof. The sheeting that is nailed to the roof slides behind the 1 x 3. I also notched the back side of the 1 x 3 with my planer to give the sheet more room to slide.

 

There is a lot of preparation to do before I can paint the shed. I need to calk all around the edges of the sheeting and fill all the gaps because I want to make this OBSRVATORY as dust proof as I can, then again I live in the desert what else is there but dust.

 

To strengthen the rails I added three 2 x 4 x 12’ lengths of lumber to each rail, two on top of each other and one on the side to tie the other two together and the rails are secured to the lumber with screws. In the upper left image you can see where the support for the rails butt up to the shed, they are not attached to the shed only the rails are continued over the upper walls of the shed. In the upper right image you can see the rails and horizontal supports extended out past the vertical supports.

In the lower image you can see two of the three horizontal supports for the rails, the third support is on the back side from this image and laid flat on the edges of the other two (hope that made sense) the entire horizontal support is nailed with 16d nails doubled (side by side) and placed every 6' to make the support at strong as possible and to eliminate sag in the long span between the shed and the vertical supports. I could have used a steel I beam but this is, after all, only a temporary structure. The 2 x 4 in the back ground with black pain is for horizontal stability at the end of the rails.

 

 

Here is the roof rolled back and ready for use. I have some more trim to do and I will be painting the entire shed, inside and out but I will wait until close to the end of summer when I know it is all dried out and there are no other modifications I want to make to it. There will be some indoor outdoor carpet installed and shelving for all the equipment. I have a ways to go before it is complete but for now it is fully functional. Now I don't have to drag all my equipment out every time I want to use the scope.

 

I have just ordered a Mountain Instruments MI-250 mount which will be here around September which is about the time I will need to paint the shed.

 

I will soon have a wooden sign mounted on the shed which will read:

 

OAK HILLS OBSERVATORY

 

The entire project took just over two weeks and cost around $750.00 and well worth the time and money.

 

05-18-05

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