If you measure the way Tony says you are missing something in my opinion.
Different combinations of spreader arm length and angle can result in a same distance from chord to mast.
Therefor I would suggest to measure:
- Spreader arm length (from mast to wire)
- Distance from chord to mast
- tension on diamond wires
- prebend in the mast (result of the above)
(and ofcourse windspeed and crewweight).
For easy comparison Spreader arm width is also handy.
Any one interested in a comparison?
Send it to me and I'll gather the info in an excell file.
(The Capricorn has only a couple of lines on diamond settings but very understandable and interesting ones).
Gill
It's true you could have the same rake measurement for different length spreaders at different angles but I have never seen this setup on a cat, only on dinghy shrouds. Most cats have either one fixed and one adjustable spreader tube per side, or a rigid blade type (fixed or angle adjustable - not length). Do any cats 'tune' with different length spreaders?
The principles of setting up a prebend rig are explained here
http://www.hurricane59.com/rigging_sailing.html (sec 1-4) and can be applied to other cats. Obviously the settings will be different from class to class, but also within a class/formula if different sections are used or if there is a distinct variance in mast stiffness. However the tuning principles should be the same.
Cheshirecatman
