[Public-List] RE Sail Track Fastening..... main sail trim.

[Don Campbell]

    There are a couple of other comments on the sail track for the boom. 
The first is that the original rigging was designed to be used with 
cotton, canvas or early dacron sails. We have much stiffer sail material 
now even if the first sails were dacron. The improvements in these 
synthetics have been major over the last 40 years. The second point is 
that we are now adding new technology to these boats and so multi-line 
rigging is used for downhauls, vangs and outhauls. The biggest strain on 
the gooseneck occurs with vangs. With the price of Garhauer solid vangs 
as low as it is  and the vang design as strong as it is, it is not 
difficult to pull this track off the mast with vang tension (usually 
applied when the boom is at 65 or 70 degrees off the boat centreline so 
shearing the bolts rather than compressing the bolts.).
    It is also not difficult to put a 12:1 ratio on the outhaul for 
adjustment anytime under any wind strength with the currently available 
stock of strong small blocks that will fit easily into the boom. The 
original sails would not last with that force on them.
     These things are still a compromise and it is necessary to estimate 
the forces generated and the weakest points in the system. Then there 
must be understanding applied when things are tightened down to sail.
Don

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