Tuning Rig

[dvhartley]

Good Ole Boat did a story about tuning your rig, and how to do it. Does anyone know what or where the specs. for the 27 are located?

[thedavo]

Mr. Hartley, I have recently purchased a device called a Loos Gauge. It is a tension gauge that basically gives you a number that converts into pounds of pressure. The instructions pretty much said that manufacturers of sailboats choose the diameter of their rigging to match the amount of load they design into the attachment points. Without the gauge, the numbers are of little use to you but if I recall correctly, the pressure for the upper and lower shrouds were somewhere in the neighborhood of 525 pounds. I have an adjustable backstay so the pressure on the fore and back stays are nearly zero when I am at the dock and tension it under sail to desired sail shapes. The unit is available at West Marine and probably elsewhere as well for roughly 65 dollars. I recently had a new set of North Sails made and they were designed to have a straight mast for the most part without any prebend induced while the boat is at rest. I would expect that is the norm for most other sailmakers as well. Hope this helps. Dave.

[thedavo]

One other thought came to mind that I forgot to mention in my earlier post. To confirm that  your masthead is centered over boat, hoisting a metal tape measure up on the main halyard to the top of the mast and measuring to the base of both of the upper shrouds is probably more accurate than using just the mainhalyard alone as the halyard will stretch far more than the metal tape measure.
I seem to recall that the main halyard rides on one of two sheaves which means it is not set absolutely center in the masthead. But, I decided that the effect on the vertical distance measured was negligible. Especially since we do not exactly have world-class racing vessels. Dave.