Thanks David,
The plan is to have a 10' tall mast, and attach the cable 10' from the bottom
of the tower, giving a circa 45 degree pull when the tower is horizontal.
Do you know a formula a non-engineer could use to calculate the pull? The ones
I find are all based on Newtons, And not the one I know, Fig.
Mike NF4L
On Feb 3, 2014, at 8:59 AM, David Robbins <k1ttt@verizon.net> wrote:
> yes, the pull on the cable goes up quickly as the tower tilts... it can be
> way more than the weight of the tower, especially if not connected at the top
> of the tower and if it doesn't have enough height.
>
> also, think about the pulley system again.. if you go to 2 or 3 to one
> advantage you also have to handle 2 or 3 times as much cable on the drum...
> AND have to run the winch for 2 or 3 times longer to wind or unwind that
> cable. getting that advantage does come with a cost!
>
>
>
> Feb 3, 2014 08:54:30 AM, john@kk9a.com wrote:
>
> I am not a mechanical engineer, wouldn't the pull on the cable be
> significantly more than the weight of the tower when tilting it? Then you
> plan on running a 55 amp motor with a 20 amp power supply?
>
> John KK9A
>
>
> To: towertalk reflector
> Subject: [TowerTalk] HF winch
> From: Mike Reublin NF4L
> Date: Mon, 3 Feb 2014 07:46:27 -0500
>
> I picked up a 2500 lb. rated 12V. winch from Harbor Freight intending to
> use it
> for tilting my HG-70HD tower. Weight with antennae and rotor etc. is between
> 1200 and 1300 lbs. I was hoping to run it from a 20A power supply.
>
> I plan on a pulley arrangement that will give me a 2:1 advantage. I could
> go to
> 3:1.
>
> If I read the specs right, the winch draws 55 amps when the load is 1000 lbs.
> The duty cycle is 45 seconds on, 14 MINUTES off. Mounting is 2 bolts,
> M8-1.25x35 mm.
>
> Seems a tad sketchy. Your opinion?
>
> 73, Mike NF4L
>
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