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This completes the permanent pier project, a mounting custom built to hold the Meade Ultrawedge and the 12" LX90 GPS. This is my own design but borrows from others I have seen on the Internet. The big decision was wood versus steel (or aluminum). I finally chose wood as it has better vibration-dampening characteristics than steel. These are solid 1 1/2 inch thick pieces of oak plywood, glued and pressed together to form a top and a bottom plate. It is adjustable for leveling and there are adjustments to allow the Ultrawedge to be moved as well. This still uses a shortened version of the center bolt with the knob and Meade compass. The yellow bubble level I set in place on the front reads ... perfectly level. :)
Here, the 12" Meade LX90 sits atop the permanent pier, on a mount built specifically for this pier and for the Meade Ultrawedge. A power receptacle will allow the telescope, computers and other accessories to be plugged in without having wires crossing the floor of the observatory.
HOLY COW! I put the level to the pier and it registered level. I figured I'd screw something up, you know, being an author and all, not one to get his hands dirty in concrete and better with words that conceptual engineering stuff ... but it came out LEVEL! This only means one thing ... if I can do it, you can. So far, my total cost of the pier is a LOT less than $100. This will be updated as I continue on to mating the telescope to the pier...as Tom Petty says ... the mating is the hardest part ... LOL!
The next challenge is designing and building an adapter system that will accomodate levelling and polar alignment corrections with a minimum of flexing and superb performance in vibration dampening. I'm considering steel, wood or aluminum. Once I make up my mind, I will design a custom solution and it will be included on this blog. Thoughts? Experience? Weigh in ... I'm sure a lot of people can benefit from your wisdom .. myself included. Thank you!
If all goes well, and you follow these VERY simple steps, you'll have a beautiful pier just like this one! I can't believe how easy it was, though it took half a day and several beers.
In several astronomy-related Yahoo groups I dabble in, the subject of rebar has come up over and over agian. Some insist on it, some don't. I think it's application-specific, though many of my esteemed online associates disagree. The pier is already encased in 3/4 inch polymer tubing ... the concrete is not going anywhere, it seems silly to me to reinforce it with rebar, especially if the concrete is mixed and poured correctly. But yes, I did throw in some rebar just to keep the pier-hippies happy.
I mentioned earlier that the most important part of all this is keeping it level. Here, I screw wood pieces into the floor to hold the pipe in place. Of course, if you're doing it RIGHT and building the pier first, you'll have to come up with a different method since there will be no floor (yet.) But it makes for a boring blog. This, I think, is unique. And works very well. :)
I can do this all day but if I forget to put in a picture of the concrete, I'll hear plenty back from those who want to see the concrete. Trust me, I've done this before. I mixed 13 bags of concrete, one bag at a time, in a wheelbarrow. Use 1 gallon plus 1.5 cups of water per 85 pounds of concrete. Mix well. Take a picture. Get a blog. It's that easy!
Perhaps most important of all is keeping your pier as level as possible. Of course, I'll be able to make levelling adjustments later at the plate level but the "more leveller" ... the better! Here is the bubble level I used to level my tripod-mounted wedge ... I'm using it here and it works like a charm!
Looking down into the empty sewer pipe as it is fixed in place, ready for rebar and concrete.
The 8 foot polymer sewer pipe is massive and hard to handle alone - but I did manage to get it upright and slide it into the hole. It was a tight fit and it knocked some crud down from around the rim, but I had dug deeply enough to make sure it would seat properly anyway. Wow, that sounded weird.
Reminds me of the old joke: I've been better legs on a piano bench. Anyway, here is yours truly cutting the notches out of the bottom of the pipe. A good Sawzall makes short work of it ...
Here is the hole, prepped and ready. Remember, it is a teardrop shape ... larger at the bottom than at the top. This will allow concrete to expand and form a heavy keel.
When deciding to build a permanent pier for my large telescope, I decided to just put on my engineering hat and figure out a way to do it ... without a lot of outside influence. I'm using a 14 inch sewer pipe (3/4 inch thick polymer, heavy!!!), filling it with concrete and going from there. As I dig the hole in a teardrop shape, I have to cut large notches in the bottom of the pipe so that concrete can freely flow from the pipe to the ground cavity.
Let me give you a tip. 13 bags of concrete handily fills an 8 foot pipe with barely any slop. But don't try to load them all into your new Saturn. I can't believe I saw someone trying such a feat. Make several trips. Or get a Dodge 2500 Cummins Turbo Diesel and THEN you can do it in one trip. :)
As I've already confessed, I'm putting in my permanent pier bass-ackwards. The observatory has already been built, so now I'm cutting out part of the floor and digging a 4 1/2 foot deep hole. I bought a really neat pair of scissor-action post hole diggers that made it possible to go down three feet in about 30 minutes. But then .. I hit water. That's what happens here in the Pacific Northwest. I'll keep at it and pretty soon, I'll be able to place an 8 foot pipe into the ground with rebar and cement and all the trimmings. (The pipe you see to the left is the actual pipe that will go down into the ground.)
It's backwards to build a pier into an existing observatory but I have little other choice. Here, the heavy black 8-foot sewer pipe is delivered - this will be set deep into the ground and filled with concrete. An adapter plate will then be built to permanently mount the 12" Meade LX90 GPS to the pier.
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