Anchor bolts for Skyshed POD
Posted 21 November 2012 - 10:55 PM
Posted 22 November 2012 - 02:30 AM
Posted 22 November 2012 - 12:10 PM
Don't place any anchors in the concrete before you finish your POD installation. As you do your POD installation you'll need to move the base around a little bit (to get the top of the walls circular so the dome rotates really smoothly) but sometimes the base of the walls won't be exactly circular and the bolt holes may not line up with what you've already installed in the concrete.
You will be much better off to use a common hammer/drill and a concrete bit to drill a few holes where the POD mounting points finally end up. No you won't need to do all 12 ... 6 will be very sufficient.
1/2" x 3-4" long lag bolts work very well when attaching to a wooden deck surface but for concrete you can get away with smaller diameter bolts. Once you drill a suitable hole you can add metal insert and then use something like 1/4" diameter bolts to hold the POD down. The size (diameter) of the holes will depend on what type of concrete inserts you can get locally.
Using some drilled holes with soft metal concrete inserts will also allow you to move the POD's position in the future once you figure out what type of pier offset will be most appropriate for your setup.
Yes an offset position for the pier is usually a good idea. It appears that the most popular amount of offset is around 16" (this is from some research and my questions to a number of POD owners a few years ago as I was planning my POD installation). Much more than 16" and you will seriously reduce your ability to move between the mount/pier and the wall on the side of the offset. The final amount is dependent on the type of mount/scope you have, how much room you need to have inside the POD, and to some extent your local viewing conditions (latitude, any obstructions, etc.).
I offset my pier a small amount (about 6") and used it for about a year like that before I then added a PZT to remove any zenith access issues.
Posted 22 November 2012 - 06:02 PM
I have an XL3 & have moved it around a fair amount to get the "perfect" spot. I still haven't quite found it & it's been 2 yrs.
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