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Nav
 
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Lot's of excitement but none for you -sorry I'm taken. Losing interest
in CM are you?

Cheers

Lady Pilot wrote:

Have you ever had a girlfriend, Nav?

You are incredibly smart...but incredibly boring at the same time.

Any excitement in your life?

LP (curious minds want to know)


"Nav" wrote in message
...

Just for fun why not do a simple engineering calculation for us Doug?

For simplicity let's say the rig has mast without any stays.

Mast 20' vertical Boom 10' horizontal. Gooseneck 3' from base of mast
Vang attched to point 3' from goosneck. 200 lbs to be lifted.

What is the bending moment on the boom at the vang if the load is held
by the vang?
What is the shear stress on the boom the load is held by the vang?
What is the compression force of the boom at the vang attachment?

Now let me quickly solve for the topping lift case:

If a topping lift is used, the bending moment at the vang is 0.
If a topping lift is used, the shear stress is 0
If a topping lift is used, the boom compression is 200 x 10 /17 = 118 lbs.

What is the maximum stress at the vang attachment point in each case?

Cheers