[TowerTalk] Homebrew Crank-up

[jimlux]

>> that could beused for about 75 feet of 55G or 65G that would
>> telescope into about the
same length of larger tower (33 inch face, 3 inch legs), probably using
an extra large prop pitch to raise and lower for 48 hours a few times a
year dependent on good weather :-) ?
>> 
> As for the prop pitch motor, some of the older ones properly geared 
> certainly could do the job, but regardless of what you use I'd want
> some thing with readily available parts, or a spare unit on hand that
> could easily and quickly be interchanged with the other. One thought
> is a winch like they use on the front of 4 wheelers when "mudding".
> 
> Good luck in what ever use you put it.
> 

Those winches don't have very good duty cycle behavior.  This is going 
to be BIG and HEAVY.  I'd get a real AC motor with a suitable gear box. 
   Say it weighs 1000 pounds and you want to push it up 60 feet. A 1 HP 
motor will push that up in about 2 minutes, with no loss (1 HP =550 
ftlb/sec).  Obviously, there will be a fair amount of loss.  Either 
you're geared so it's like 10-15 minutes to crank up, or you're looking 
at a 5 HP motor. (counterweighting might be reasonable.. The lower 
section is going to have beaucoup compressive strength, so carrying 
twice the mass of the upper section won't be a problem.