Thanks for the clarifications. Also, your previous response
"Shake rattle and roll, I love them all" was helpful in setting a
congenial tone.
<<Trying to win his argument on deception vs truth. >>
A worthy goal.
You're right that the teeter-totter doesn't get much heavier based
upon which side the load is on. However, transmitting the fore/aft
loads from the shorter ww hull of an atlantic proa requires
substantial torsion forces in the beams to get the loads to the
longer lw hull. Keeping the rig in the lw hull substantially
reduces these forces.
I think the only way to resolve the lighter-beams argument is to
have an engineer design for the stresses. Does "substantially lower
torsion and racking forces" translate into less structure and
lighter beams? If so, by how much? The only way to answer that is
with finite element analysis.
I believe this has been done on the harry's, visionarry's, and the
upcoming solitarry. I'm not aware of anyone having paid to do the
analysis with the same setup on a windward rig (everything identical
except for rig location and structure required to deal with it).
That would be interesting. Not interesting enough for me to fund
it, but definitely enough to applaud someone for having it done.
- Mike
On 11/15/2010 1:25 PM, tsstproa wrote:
Retort in reverse to Robs post.
When I usually ask for help I usually get a very general or vague answer.I stopped asking for help along time ago. I agree the beam thing is complicated but in theory my general statement still stands and you have yet to prove it wrong.
I said I don;t see how or why Robs beams would be any lighter than a pacific or a Atlantic. I would add that even if they where the significance would be nominal over what Robs Lends it to be. Tetter- totter ever play on one? The balanced beam weight plays very little roll It just needs to be strong enough to support weight at each end.
Luck had everything to do with it. Good thing more bulkheads didn't pop or worse yet have the hull tear when the bulk head popped.
Read your own post and for an example the latest one by another poster. Misrepresentation in communication turns into who can win an argument vs truth. Chess game really.
>Nothing has been said here making holy grail claims; only that a >weight-to-windward proa with a lee sail is a way of creating lower >stresses than most other designs. Don't agree? Fine.
Nothing against you Mike. But Holey grail was a In reference to Robs holding back on beam wall thickness tapering due to his assumption of my knowledge again. What he thinks I don't know! Trying to win his argument on deception vs truth.
If Rob you are referencing that your beams are lighter due to your boat having the middle platform that also is a support structure between hulls making your conventional beams lighter than need be. I'd agree, possibly.