I can't help with ques #1, but for question #2> Throwaway the aluminum
mast. Don't use it. The only aluminum on a tower should be the
antennas and associated mounting plates but, no masts. Especially such a
l o n g one. Long masts need strength and aluminum can't hack it, even
6061-T6. Get yourself a 24 ft chromally mast. You ought to see my
118,000# yield strength, 18 ft chromolly mast, bearing at 134 ft, with
25 sqft of antenna moves in the 60-70 mph winds we get twice/year. Then
answer your question mathematically. Don't even think about aluminum.
Many many horror stories can be re-told about such masts. There will be
others on this reflector who will tell you how long their aluminum masts
have been up. Others will tell you how long their aluminum towers have
been up. I for one need to be able to sleep at night. (I even have
galvanized steel inserts in the aluminum booms of some of my antennas!
So do some of my friends!!)
Visit my web site: http://www.erols.com/n3rr
Bill, N3RR
donald.s.tucker@exgate.tek.com wrote:
>
> Hi,
>
> Just subscribed and seeking some help.
>
> Question 1. I have acquired a like new Triex T-51 3-section motor driven
> crankup. I built the base and poured the cement according to Tri-ex
> instructions and even made it a little deeper and wider, both ways. I
> included and installed in the base a 20 foot 4x4 steel tube which I had and
> will use it as the tilt-over support and a wire antenna leg. What I am
> looking for is a 2-way locking hand winch that I can use to tilt the tower
> over on its hinge and pull back up knowing that I am doing so without the
> possibility of losing everything. All I can find is a 1-way hand winch such
> as used for boat trailers. Would appreciate any suggestions or pointers as
> to where I can locate such an animal or a work-around and the size and
> strength of steel cable to use.
>
> Question 2. I have a 2 inch 6061-T6 1/4 wall 24 foot piece of tubing which
> I acquired to use as a mast in the above tower. Want to mount my TH7DXX, my
> KLM 40M monopole, and a 12 ele 2M beam. My intention was to place a plate
> with a bearing where the original rotator goes, and put a new rotator plate
> further down the tower, to take any stress off the rotator. My concern is
> how much mast I could (should) leave out with the antennas noted and if I
> could sneak in a small 12/17M beam.
>
> Don W7WLL
>
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