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gonefishiing
 
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refresh my memory:
i'm looking for the section modulus for a boom section to understand
allowable bending stress.
sx= bd(squared) ?
but this is for rectangular sections right?
how do you calculate this for an oval section?
gf.

"DSK" wrote in message
.. .
Nav wrote:
Ad_hominem?


Yep. Couldn't happen to a nicer guy, too.

After the way you have acted, to get all nose-in-the-air about my poking
fun at your obsessive behavior is rather funny.


Are you sure? The geometry _is_ defined.


You're right. Lesson 1- always look the problem over thoroughly.


For the record, the compression on the boom would be the weight
multiplied by the cosine of the angle.


Are you saying it is not 118 lbs in the topping lift case?


Are you saying it's not the cosine of the angle formed by the topping
lift? Tell you what, go down the hall and ask one of the engineering
profs... if any will speak to you...

I gather that you have never heard of a "Free Body Diagram"? Freshman
engineering stuff. That is the way to solve such problems. If you
don't believe me, ask Scout.



But I'm not asking Scout. I'm asking _you_ to solve this freshman
problem -if you can.


Well, it is only a few minutes to draw up a free body diagram. I did a
rough one earlier, but it will take longer to do it on the comuter and
post it. Another job for tomorrow....

I wonder why the boom vang situation bothers you so much, or why you are
*so* sure that a solid vang cannot lift a heavy weight. I've seen it
done several times on several different boats, so obviously it can.

Hey, I got an idea... let's have a little wager on it... no wait, you
don't pay up when you lose...

Fresh Breezes- Doug King