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| The pier was constructed manually. A 5 foot deep hole, 25" diameter, was dug and filled with 20 bags of quick setting concrete. A template holding three large J-bolts was sunk into the wet concrete and allowed to cure before setting the Astro-Pier in place. Northern alignment had to be done carefully, as the Losmandy equatorial head was going to be attached to the pier. It allows for a +/-6 degree variance, so we had to be careful. To get alignment while the concrete was wet, I placed the Losmandy tripod over the hole and centered it with a plumb-line. The mount was then rotated over the hole until Polaris was centered in the scope. Marks were then made where the tripod legs had been, and these were used to align the bolt template. |
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For those interested in doing this themselves: Any hole deeper than 2 feet
become exponentially more difficult to dig the deeper it gets! For every
inch deeper, the work increases many-fold. Rocks in New England are notorious.
We hit several stones large enough to make us ponder digging another hole
some place else. If you can rent an auger or borrow a backhoe, then do so.
Our site is very difficult to get a truck into for concrete or digging, so we
did the work manually over many days. Every night, either me or my spouse would
remove another inch of dirt from the bottom of the hole. We also got very creative
in methods of stone removal. Two feet into the dig, we hit a large stone (visible in the photos) that was a real heartbreaker. I rigged up a pair of old electrical cables around the rock and "bench pressed" it out of the hole. That was an accomplishment. Sue was so enthusiastic that she dug the last foot of the hole, and even went 6" deeper that we even needed! |
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| For safety purposes, we kept the hole covered when not being worked on. There are many animals in our area, ranging from domestic cats and dogs to deer, bear, racoon, porcupine, skunk, and coyote. We didn't want any of them in the hole, and we didn't want anybody in the hole either! |
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| Half way through the dig, we hung up some Buddhist prayer flags to support world peace. There's my political statement for this webpage ;-) |
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| A frame was constructed of 2x4 to contain the edge of the poured concrete. This gives a more professional look and feel to the completed project. Note the yellow "tags" in a triangular formation around the hole. These are squares of "Construction Warning Tape" which were nailed into the ground at the exact spot where my Losmandy Tripod legs had been. These were used for polar alignment when setting the bolt template into place. The template can be seen in the left background of the image, preassembled, and ready to use. |
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| This is Greg, an invaluable help in purchasing, hauling, lifting and mixing the cement. He's even still smiling in this image. Thanks!!! |
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| That's me, looking as silly as possible. The project seemed larger and harder than it actually was. In fact the hardest part was digging the hole. Mixing many bags of concrete was not too bad. It took about an hour overall to mix and pour. We worked in well-choreographed shifts of hauling bags with the wheelbarrow, mixing, two at a time, pouring, repeat... |
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| The completed pour. Note that in normal installations one wouldn't have the pier in place just yet. In this image, the wooden bolt template is still intact while everything settled. We happened to use Quickrete, a brand of fast-acting concrete used for post holes. It hardens to an unworkable state in under 40 minutes, so we had to work fast for the last few bagfulls. Getting the template and J-bolts into the concrete proved quite the challenge. We pushed, and pushed, and even danced on top of the template to sink it down into the hole! During all this, one of the bolts went in at an angle, so we had to verify that the pier would still fit onto the bolts. We got it on, so we left it there as added weight to settle the bolts into place. It pretty much levelled itself as well. We covered the top of the wet concrete with plastic bags and wetted it down a bit to enhance curing. |
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| Greg looking happy and holding his favorite implement of destruction. |
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| That's me looking satisfied. Now all I have to worry about is making sure polar alignment can be achieved. |
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| Here is the finished project. On the pier is the Losmandy G-11 equatorial head whch bolts perfectly onto the Astropier. This image shows the system with the Takahashi FSQ-106n refractor in place, but my other scopes also fit onto the mount with the Losmandy dovetail system. |
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| The equatorial head has been attached along with a scope. This is a shot taken on the night of First Light for this pier. The moon was visible at First Quarter and made a fine show in the Takahashi. With the scope is Susan, my loving spouse, without whom this project would not have been possible. |
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| One satisfied customer! That's me with the finished project. We tested the northern alignment and discovered that the pier was 3° off from true north. That is well within the +/-6° azimuth adustments that the G-11 is capable of. Needlesss to say, I was ecstactic! |
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| Here is the newer C8 ready for an evening of imaging. Note the shelf unit on the pier. This was made by bolting two short 1x6 pieces to each other on alternate sides of the pier. A piece of 1" thick board acts as the shelf and has a 6" diameter hole cut in its center to fit over the pier. The shelf can be raised or lowered on the pier by lossening the bolts holding the 2x6's. The shelf can also be freely rotated about the pier to make observing more enjoyable. |
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