Figuring loads / block & tackle theory
The same thing applies to a sailboat rigging. The more pulleys on the boom,
the more vertical lines and the less force you had to apply to hang on to
the main sheet. I has a small boat that had two pulleys, four vertical
lines on the main sheet. If there was only one pulley the force of the sail
would have pulled me right out of the boat.
MLD
"The Other Harry" wrote in message
...
[On Fri, 12 Mar 2004 19:36:49 GMT, "Michael Daly"
wrote:]
snip
Plug in different values of a for the angle of the line
running to the cleat and you'll see that the vertical
force on the top support only drops to equal the
weight of the load if the line running to the cleat
is horizontal. That also creates the maximum
horizontal load on the support.
Just so I understand this...
What I think you are saying (without trying to put words
in your mouth), is that if I want to reduce the tension on
the eye hook, the way to do that would be to hang the
cleat so that the angle of the line from the eye hook to
the cleat is above the horizontal. Less than 90 degrees.
If I place the cleat lower than 90 degrees, I will be
actually be increasing the load on the eye hook. The
closer to vertically down I get with the cleat, the more
the load on the hook will be. Up to double the original
weight of the pot.
Sound right?
Now then, what about the block & tackle gear between the
pot and the hook. Forget about the cleat for now.
Would it make any difference if there were more turns in
the line?
It's not that tough - I learned this stuff when I was 12.
Oh, hell no. It's just mind boggling.
--
Harry
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