Sunday, August 3, 2014

Pier has least parts.

Yesterday we went over to Pacific Industrial Supply in Seattle to find something to use as a pier for the scope.   I found pretty much what i was looking for.  The metal tube is 8x8 inches, 1/4 inch thick, 4 feet long, and weighs 130lbs.
I got a 25x12 inch slab of metal also that will be cut into two 12x12 inch plates to weld onto the pier for the bottom and top supports.
The old mounting plates
The other photo shown is my old mounting plates from the old observatory.  The plate with 3 holes was mounted on the top of the cement pier, and the one with multiple holes was the top plate the telescope was mounted to. Reviewing polar alignment I did remember that it doesn't have to be perfectly level since all you are doing is pointing the axis of the rotating mount toward the North celestial pole.  So with that fact, I'm thinking I'll do away with the double plate mount I used on the old one.  Sure, I'll get the pier as level as possible, but it's not critical unless you are using an Alt/Az mounting  - which would be foolish for imaging anyway!  The observatory will be pretty much perfectly aligned with true north, so the pier will be mounted nice an symmetrical on the floor.
Traci has a coworker at her doughnut machine factory who is an expert welder and is willing to help with welding, cutting and drilling, so we are in good shape with that.
Total cost so far (before welder friend's labor) is $160 for pier parts.   Commercial piers of this size are easily $800+.
Now back to working on the power trench....

Won't even jiggle in a 6.8 earthquake!

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