Dave,
I shudder at you story, and because of it, I won't have to shudder at mine.
Thanks.
Interventions rock!
Mike NF4L
On Feb 3, 2014, at 1:54 PM, David Gilbert <xdavid@cis-broadband.com> wrote:
>
> 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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