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Pier for 1100GTO #Guiding
Hi Len,toggle quoted message Show quoted text
That is a very nice pier. What you say makes a lot of sense. It looks like the sides were rolled to produce the shape.
On Saturday, March 20, 2021, Len Fulham <lfulham@...> wrote:
Embedded or bolt attached pipe piers are commonly and successfully used, but they have an inherent tendency to resonate vibration. Filling with sand or concrete changes the frequency and maybe amplitude without necessarily improving damping as might be expected.
"It looks like the sides were rolled to produce the shape."
Don, yes/no. I had a boiler-maker make it but there was no roller. A press was used to progressively make small bends to form the shape. I made a cardboard template with bends every 4" for him to work to. I do like the pier that results. On a different scope I replaced a pipe pier (8" dia, 60" long) with a similar tapered pier with great improvement. That one had a 16" base tapering to 6", 60" high but was asymmetric - the Nth side was flat so the equipment C.O.G. was kept over the pier foot.
Made of steel these piers are quite heavy, but not intended for portability! Could be made of aluminium of course.
As mentioned a straight sided tall pyramid pier would probably be just as stable but has greater bulk higher up where it might affect a long scope.
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