It seems the construction/manufacturing tolerance is why the sailors have found masts with different stiffnesses. Skiffness of the mast is a function of dimensional properties and physical properties.
Aluminum dimensional properties will vary
http://www.almag.com/tolerances.htmYes, you can reject masts, but at what cost?
In the manufacturing world no one likes their product to be rejected.
What dimensional tolerance are the sailors willing to pay for?
For aluminum physical properties, to my expensive/suprise I have found the Modulus of Elasticity (Young's Modulus) for one sample of aluminum alloy 6063-T6 to be 9 msi, when it is supposed to be 10 msi (10 percent difference) How is this possible?
For carbon dimension properties what if someone misses a layup?
How are dimensional properties of carbon mast going to be checked?
For carbon YM I have found it can vary from 30 msi to 100 msi.
Someone could accidentally ship 40 msi carbon fibre.
How is carbon YM going to be monitored?
Rather than the TRADITIONAL quality control of the dimensional and physical properties of each mast to decide weather to accept or reject it; use the RESULTS OF the above properties AND field measure the deflection/stiffness by placing a weight. (I don't think to many extuders would be happy doing this, but you get what you pay for)
Some type of mast rating system could be used; ie, this could be based upon tip or midspan deflection in both major and minor axis.
Again, measuring the RESULTS OF the manufacturing process, after all the sailors are interested in the results/stiffness not the thickness or YM. (provided of course is it properly designed for bending and shear)
The resulting measure of mast stiffness could then be catalogued to crew weight (but how many catagories is another thread)
