How much tension for rigging.

[Marc]

I am rigging my oday 22 and I have use of a standing rig tension gauge. Does anyone know how many lbs. my 1/8 in. cable rig should be for the shrouds and stays.I have heard that the shrouds are prone to pulling out the chainplates. I have 'beefed up' my chainplates by extending the steel down the interior bulkhaeds with additional bolts, looks real shippy too.Any thoughts would be greatly appreciated.Marc.

 

[Don Evans]

Rig Tension

Following conservative tensions, the breaking strength of 1/8" is about 2100 lbs. For the cap/uppers 15% would give 315 lbs. For lowers 12% would be 252 lbs. Aim for these values and adjust up or down depending on personal preference and type of sailing. Excellent decision to beef up chainplate attachment points. Something we should all be conscious of.Don

 

[Sergio]

Tension

Hi Marc, I have a 22 also and I read somewhere that the shrouds should be just taught and the fore & aft stays should be tight. All adjustments should be done by hand only.Bear in mind, that for every pound of "pull" the wire has, is also a pound of "push" the mast exerts through your ceiling and cabin deck.Hope this helps

 

[Dave]

Not exactly -vector components

The vertical force on the mast is the vector component of the sum of the assorted shrouds and stays. A cable can be loaded only in tension so the load in the cable is along it's axis. The force exerted downward by the mast is the force in the cable times the cosine of the angle between the cable and the mast. Now summ all the forces for the total force exerted by the mast on the deck step or keel step.dave

 

[Ex-math wizard]

KISS means: Keep It Simple Stupid...

Just remember, the right angle (at the mast step) , the hypotenuse (shroud), the cosine angle (at chainplates) and the adjoining side (tumblehome) are all distorted with too much tension. Wait,... what I like about sailing is its simplicity. Colgate's Basic Sailing book defines shrouds as: "wires that keep the mast from falling over the side."We tested the cable tension on aircraft control cables. For everything to work right, we followed recommended tension readings.My O'Day shrouds and stays seem to work fine with the tension recommendations simular to Sergio's suggestions.KISS works for me. Note: (I'm the stupid one here, not anyone else.)