In article , qedude
wrote:

I'm hoping someone can help me with a problem I am having. I have a telescope
mounted on a 54 inch tall, 3/16 inch wall, 8x8 square aluminum tube with 1.25
inch plates welded to the top and bottom and bolted to 2/3 of a yard of
concrete. The problem is I am getting a little too much movement out of the
tube and I need to increase the stiffness of the tube. The ideal situation
would be to replace the tube with something larger but that's just not
possible
at this point in time. I don't need a radical increase in stiffness either so
I
think there is something I could do to for a slight increase in stiffness. I
need to kill low frequency vibrations so please don't suggest sand or
concrete,
beside concrete and alumimun don't get along with each other. Any ideas ?
Would
putting the tube under tension help ?


Scott Hogsten



Anchor forged eye-bolts to the 4 corners of your concrete pad and
connect steel cables from the eye-bolts to the top flange of your tube.
Use turnbuckles to adjust tension.