Shadow of the Mountain Observatory

Shadow of the Mountain Observatory - The Build

May 20-22, 2011: Gantry

5/21/11: My first task this weekend was to get those 3 remaining siding panels in place. Done. Now time to go start digging holes for the gantry...

5/21/11: My buddies showed up and we took the opportunity to drop the pier onto the footer. As seen here it is sitting on 2x4 blocks. Later we removed these and leveled it up with some shims and got her bolted down nice and snug. Getting that heavy pier down in that hole was an interesting problem. Basically, we stacked up 2x4 scraps and rolled it on. Then by rocking one way and the other, we removed one block on one side at a time and "walked" it down onto the bolts. I breathed a sigh of relief when it dropped onto the bolts with no issues. Fill it with sand, throw on the mount and scope and we are operational baby!

5/22/11: The gantry is the frame that holds the roof in the rolled off position. For this to work properly the top rails have to be perfectly flush, level and aligned with the top of the east and west walls. Further, the posts have to be placed at the correct distance from the building and in alignment with the walls as well. And of course everything has to be plumb and level at the same time. Thanks to Steve and Don for helping on this step...it was very tedious and took a number of iterations to get right. In this pic the first two posts have been set and are held in place with a couple bracing boards. My hands are blistered from digging those holes...lots of rock!

5/22/11: After getting the other posts placed, braced and squared up we deciding it was a real good idea to pour the concrete. Each hole has at least two bags of 80 lb. ready mix concrete and topped off with dirt. We let this set up for a few hours...had some lunch and went over to Steve's property to help get his foundation started...

5/22/11: Later that same day we marked and cut the tops of the posts off. Again precision is important here. Cut in the wrong place and the rails will not be level causing roof movement to be more difficult than it needs to be. Two of the timbers are notched to fit into the walls (you can see these notched holes in previous pics). With a little bit of fussing, squaring of ends, and some more creative notching we got everything lined up perfectly. I couldn't be more pleased with the result. Thunder storms are on the way and its getting on the late side, so we quickly installed a couple of collars to keep things squared up. Just to be on the safe side, I decided to leave the bracing boards on until I can get more permanent bracing in place. When I return next time I will add some more diagnol bracing to support the rails at the midway points.

5/22/11: Another view looking south.

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Shadow of the Mountain Observatory - The Build

May 20-22, 2011: Gantry

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