"DSK" wrote in message
| You said that the shrouds "disperse" the load, which is crazy. Shrouds
| keep the mast from falling over, at the cost of placing the mast under
| compression. A side load on the mast increases tension on the shroud,
| which increases compression on the mast. So, the compression on the mast
| will *always* be greater than the weight load placed on it... and that's
| not taking into account the static tension on the rig (pre-load).

Okay I can agree with the premise that the shrouds provide stability [via
tension].... but the fact that they are attached to the mast indicates
that a transmission of stress is allocated to the shrouds.


|
| The difference between a boom holding a heavy weight, supported by a
| topping lift; and one supported by a solid vang is this:
|
| The topping lift will transfer the weight to the masthead, increasing
| compression on the mast. The shrouds keep the mast from falling towards
| the weight, increasing compression on the mast. The boom is in
| compression, keeping the weight from swinging in towards the mast. The
| compression on the mast & tension on the shrouds place a torsion load on
| the hull.

I concur.. that seems to be a logical dispersion of forces.

|
| The solid boom vang will be in compression. The boom will be in torsion
| between the weight pulling down and the vang pushing up. The mast will
| have a torsion load on it from the gooseneck to the lower boom vang
| swivel fitting.

Again I concur...

|
| Last but not least, booms supported by solid vangs will (if properly
| engineered) hold up weights at least as heavy as a medium size adult.
| Ask me how I know this for a fact!

Although I agree with this... my argument was regarding the actual load
capacity between the vang and the topping lift. My point is the topping lift
is able to handle much greater loads than the vang ever could. On this
aspect I stand my ground.... the topping lift has the mechanical advantage
over the vang.

CM


|
| Fresh Breezes- Doug King
|