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Mounting the dome
As your telescope slews and tracks it's way about the stars, you need the ability to move the dome slot with it without excessive effort. At first you can do this by hand, just pushing the dome around as the telescope moves. If the your telescope is motor-driven, then later you can fit a motor drive to the dome and synchronize the two. Your imagination has no limits.
This is a task that requires patience, a lot of tinkering and fine tuning. At this stage the dome is getting a bit too cumbersome for one person to maneuver so be careful of your fingers and your back. Its a good idea to get the top ring of the walls fitted with rollers and adjusted while it is still on the ground. This would be extremely difficult to attempt on top of the walls.
Make sure you get sturdy wheels for this. I got mine from a hardware store pretty cheap. I had to make up my own mounts for some of them. Use your own initiative here and try a few ideas.
To stop the dome from rolling off to one side, the guide wheels need something to guide. On the inside edge of the dome support ring, I screwed a two-part band made of a long strip of particle board and strips of 5mm grey plastic sheet. A bit like Perspex only softer.
A wise fellow named Steve Quirk who owns Frog Rock Observatory at Mudgee, NSW (http://www.hwy.com.au/~sjquirk/index.html) gave me some good advice. "Make sure you secure the dome from being lifted by high winds". To that effect, I welded up some brackets out of, (strangely enough), more brackets. These are bolted onto the support ring and overhang the guide band of the dome. Leave some clearance so the dome does not get caught on them. I used four which I think is plenty. The damage done to the dome would be one thing if the wind got hold of it, but can you imagine what may happen to your precious telescope and camera equipment?
*AFTERNOTE* Once the dome was insulated and coated in fibreglass, it got so heavy that these were not neccessary. The theory of them is still sound though.
Lifting and Positioning of the dome on top of the building was done utilising my father's backhoe. There is nothing that man can't do, bless him! This trial lift and position is just to check for fit and adjust before the final fibreglassing is done. Once satisfied that it all fit, we lowered the dome to the ground again before coating it in fibreglass. I installed four "U" bolts around the perimeter of the dome to tie on some ropes for lifting. Make sure you tie on some rope to use as a "tag line" so you have a little more reach and control while remaining at a safe distance from the machinery and suspended load. If you are going to leave it on for more than a day, make sure you tarp it or the wood will spoil if it gets wet through rain or even nightly dew.
*AFTERNOTE* I found that the rollers I have used are too stiff and great effort is exerted to rotate the dome by hand. This will only get worse as I add the weight of the fibreglass on top. Therefore, I have come up with the idea of using a metal ring, (band) and a few specialist rollers on bearings to free it up a bit. See the update on Support Ring page. Take a look at this movie of the dome rotating:
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