I have a tripod mounted on a concrete block and an old 6 in. X 6 in. by three ft; conctrete slab the previous owner left here. The tripod holds up an aluminum pipe with an anemometer and a universal antenna. Since the area is shielded by trees about 100 ft. away, the anemometer does not give a very accurate estimate of wind speed or direction.
My fireplace chimney has a 4 in. thick slab, not reinforced, cap on the top. I am coonsidering moving the tripod to the top of the chimney cap but wonder how close to the edge would be safe to drill for the tapcon screws to hold the tripod down against the wind. We had a tornado, small one but big enough to tear the neighbors roof off and uproot some trees about 14 in. in diameter, go between my house an my neighbor's house (not the one that lost the roof). This would lift the anemometer up into \"clean\" air and make it much more accurate. The anemometer radios the speed and direction to my recording station and is powered by solar so I wouldn't have to change batteries very often. I figure 4 in. from the edge for the 1/4 X 2-3/4 in. tapcon screws. If three and a half would be OK, I could spread the tripod legs a little further apart which might be better for stability. What do you think?
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