[C320-list] Standing Rigging-Winter Layup

[Chris Nichols]

This sounds very plausible as the coefficient of thermal linear expansion for Aluminium is 22 versus 16 for stainless.
This is in units of 10 to the minus 6 meters per degree Celsius per meter

If the change in temperature is say 60 c at most then the mast shortens 1.3mm per meter versus the rigging shortening 0.96mm per meter.
I reckon that means the rig is about 4mm slacker at 30 below zero if the hull were the same shape as when in the water. 

Of course it is not. 
The debate continues!

Chris

On 25 Sep 2015, at 14:09, Scott Thompson <surprise at thompson87.com> wrote:

I was told by an experienced rigger once that the rig loosens on its own in the winter because the aluminum mast shrinks more in the cold than the stainless rigging. He said that you should not loosen the rigging. Of course the rigger at the C320 rendezvous in Annapolis a few years back gave opposite advice but didn't give a good reason in my view. Personally I can't think of a good reason to de-tune the mast. A loose rig may promote failure of parts from vibration. 

Scott Thompson
Surprise 653



> On Sep 25, 2015, at 12:12 AM, Kaare Wold <sailor3952 at charter.net> wrote:
> 
> Skippers-Here in Wisconsin we haul out, winterize, cover, and store outdoors with mast up.  Is it advisable to loosen each turnbuckle a couple of turns or is it ok to leave the rig tensioned as is?  Thanks for your comments and advice on this debated subject.
> Kaare Wold. Sheet Music #945
> 
> Sent from my iPad