let's if I understand you correctly. *your* midsheet boom has the very same
load put on the vang from a weight hung off booms end as the same load pulled
upwards on the boom about 1/3 of the way outward from the mast??

Gee, that is interesting. *you* boom does not form a lever. my, my, my. how
did you get *you* boom to ignore the laws of physics?


From: Nav
Date: 8/24/2004 10:25 PM Eastern Daylight Time
Message-id:

Not on my boom it doesn't. The forces appear at the clew...

Cheers

JAXAshby wrote:

right conclusion, wrong reasoning.

hint: the net resultant load on a boom from a load at the end *is* at the
end,
which gives a long lever arm. the net resultant load on a boom from the
_same_
load on a sail is at the center or effort on the sail, roughly where the
vang
attaches, which gives a short lever arm.





From: Nav
Date: 8/24/2004 7:23 PM Eastern Daylight Time
Message-id:


FYI:

Now this may come as a surprise, but the boom is more likely to buckle
if a rigid vang is used to lift a weight at the boom end than if the
same load is upward (as applied by a sail).

In the upward case the boom wall is being pulled out by the vang -an
effect opposed by tension in the boom surface due to the bending moment.
In the weight lifting case, the lower surface is in compression and is
being pushed in by the vang so that wall buckling is far more likely.

Cheers