Telescope Reviews: Re: It Begins

Hi Doug,

I have been looking many many times on the pier you are building and allow me to give you some points of view from my side.

I do not want to take the wind out of your sails but I see some trouble coming up with the design of your pier.

Judging from the image you posted I can see that you did not go very deep into the ground with your base. The shape of that hole is also problematic as you have a narrower bottom then the top.

¿ Why do I say that it looks like trouble ? You have a 6 feet tall concrete post with a weight of maybe 350 pounds and the center of gravity is at about 6 feet high from the bottom. Now you will put on top of it how much more weight ? in equipment and suddenly your center of gravity goes up by maybe 1 or 2 feet maybe more depending of your equipment and your whole pier construction becomes unstable.

Judging from the image the diameter of the base at the top is maybe 32" but rapidly getting smaller the deeper you digged. So maybe you have there only a base with a size of 12" diameter and 12 inches deep ? That is a base weight of roughly 130pounds. Also I assume you went with the cardboard tube nearly down to the ground. The cardboard will start to rotten and then the concrete around will be of no help. If we add the weight of your base to the pier then maybe the center of gravity slips down by 2 feet.

The single rebar ? you put in there is not a big help for the concrete. Normally you have to put in at least 3 pieces tied together with some rings. Another possible problem is that you sticked the rebar directly into you soil which can be a future problem that you rebar will start rusting inside the concrete pillar. Water creeps up by capilaritybetween the boundaries of the iron rebar and concrete. From what I have seen rebar should never be driven directly into the soil.

From your equipment desciption I deduct that you are a visual observers which implies another problem that you will be movong the scopes and you personally could be leaning on the pier and ahving such a little base in the ground you pier can easily be moved by you and become unstable.

Apologies for beeing the first one to write about possible future problems ...

Just my 2 cents to your project.

You are still on time in order to stiffen the big 6 feet pier by adding a broader concrete base especially because you wrote that the deck will be 20" above the ground.

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regards Rainer

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