About five years ago I bought an inexpensive Harbor Freight hand-crank
worm gear winch for use in a simple homebrew mast raising fixture. The
mast plus antenna weighed less than 250 pounds and the winch was rated
at 2,000 pounds. It sounded fine on paper but almost created a
disaster. The worm gear was hard steel but the toothed gear was
apparently made from mild steel because after only a few feet of lifting
I could tell that teeth were being ground away. I literally had to
apply fresh lithium grease to the teeth every revolution of the toothed
gear and after about 10 feet of lifting there was less than 50% of the
metal left on each tooth.
I also once bought a Harbor Freight crowbar ... the beefy kind (maybe
5/8 inch diameter) that you normally use for pulling large nails. I was
using it to pry something apart and I literally put a large permanent
bend in it just with my own arm strength.
There is no way I would trust anything of value to Harbor Freight steel,
and in the case of NF4L's tiltover tower there are so many things that
are far beyond good engineering guardbands (the probability of bad
steel, the >REAL< winch rating versus the load, the ridiculously
undersized motor as revealed by the duty cycle rating, the lack of a
brake, etc) that if he hadn't decided on his own not to use that HF
winch we should have staged some kind of intervention or something.
73,
Dave AB7E
On 2/3/2014 10:57 AM, Les Listwa wrote:
Hi,
Just want to share my experience with a " cheap" 2500lb Electric Winch.
Tried to use one ( actually even tried a second one) to lift a Hazer type
device up 40 feet of 45G. My load was about 300 lbs total. What I found,
is that before I had a chance to even try to lock the Hazer device in
place, the winch would begin to creep down, once I took my finger off the
up button. A winch is not designed to lift.
Also, 2500lb of torque is a powerful beast and I learned that if
something goes wrong, in a split second that 2500lbs of torque can rip
apart cables and aluminum, before you even realize there is a problem,
because there is no feedback. I learned that the hard way.
Based on the advice of John, W2GD, Antenna and Tower Installer
extraordinaire, I switched to a Fulton K1550 manual winch and had a local
welder make a custom mount for the tower. I have complete control and can
stop it on a dime. My recommend is to go with a Fulton Manual Winch.
By the way, to power my electric winch, I used a Sear car 12V battery
boosters (500 peak amps/400 cranking amp) , just left it trickle charging
until I wanted to raise or lower the antenna.
73
Les
W2LPL
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