[TowerTalk] Maasdam "Powr Pull"

[Grant Saviers]

Not 8 tons load while I'm standing next to it!  Think of the energy 
stored in the cable as it stretches and what happens if something 
breaks.  Chain falls and chain lever units are much safer, since very 
little energy is stored in chain under load.

Check out what an 8T rated sling hook costs (about $30 not lift rated 
and $50 lift rated) and its size (1/2" pin)  as a calibration of the 
spec nonsense in these units.  Also, long before you get to the rated 
load, the handle bends sideways on the small Chinese units.  Done this 
several times.  The larger units with reinforced handles, moving single 
block, and double ratchet wheels/pawls work ok if not abused.   My guess 
is about 1.5 to 2T is the practical force limit.  The best ones I have 
are branded Alltrade, are rated 3T and have single piece (not stacked 
stamped) double ratchet wheels.  Also, the cable override on the spool 
at high loads tends to be a problem and a serious hazard to unsnarl.

They are fine for fence stretching, loading stuff on tilt trailers, 
moving stuck vehicles, etc. but not safe for lifting.  Probably ok for 
temporary guy tensioning up to a few hundred pounds (the good ones).

Grant KZ1W

On 9/23/2011 7:50 PM, k6xt wrote:
> 8 tons. Wow. If this unit has your typical 18 inch handle, Rick, I'd be
> inclined to think the unit will withstand 8 tons before it flies apart,
> but the user is not about to apply 8 tons with the little handle.
>
> Unless maybe it has a series of pulleys?
>
> Caveat emptor!
>
> 73 Art
>
> On 9/23/2011 5:48 PM, Rick Karlquist wrote:
>> A question for you come along experts.
>>
>> I saw some come alongs at the Chinese tool store (you know the one)
>> that claimed to pull some huge weight like 8 tons.  Assuming
>> the user applies 40 lbs, this is a 400:1 mechanical advantage,
>> not counting friction.  This is hard to believe.  Is this
>> true of these or even the American equivalents?  Or is this
>> specsmanship where it moves an 8 ton boat onto a trailer
>> or something like that?
>>
>> Rick N6RK
>>
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