Standard rigging- DeTension or leave alon

[Ian McGain]

Most boats in the North-East are now up on jack stands. In previous lay-ups, I have de-tensioned my standing rigging. Last season I read a post that your aluminum mast will shrink in the cold weather greater than your stainless steel standing rigging.This season I did not de-tension. I now am having second thoughts about this part of my standard winterization process. I do not want to visit my boat to find two concave dents in the freeboard. Any thoughts before its to late?Ians/v Meant to Be'79 Hunter 30

 

[Don]

No problem

IanIt is true that the coefficient of expansion differs between aluminum and steel such that your rigging will contract less than the mast - effectively de-tensioning the rigging for you. It's also true that a lose rigging will allow the mast to move creating additional stress on the boat as the wind blows all winter. In combination, the conventional wisdom is that you could create more problems by opening the turnbuckles. You might want to check the archives for more discussion.Don

 

[Warren Milberg]

Rigging in Winter

I've done it both ways with my current and previous boats, i.e, some winters I've loosened the standing rigging and other winters I've just left the rigging alone. I've never noticed any difference in terms of damage, etc., one way or the other. The only "benefit" I see to loosening the rig in winter is that if forces you to lube or otherwise maintain the lugs and turnbuckles so that they won't gall -- and that is a good thing. If you do that anyway (and many do not), I wouldn't bother loosening your rig unless you keep it banjo-string tight during the season.

 

[Paul Akers]

I Don't Think the Boat Yards Loosen It

That should answer the question. Otherwise, we'd see a lot of banana-looking boats floating on the bay in summertime.

 

[Bill O'Donovan]

Downside

Loosening would compromise whatever fine-tuning you had in place, unless of course you count the turns and record it.

 

[Doud]

Seldan Manual says to loosen it.

I read the manual from Seldan mast maker for my Hunter and many other boats. They say very clearly to loosen tension if you are storing with mast up. They designed it,so I believe them.

 

[Alan]

Seldan Manual says to loosen it.

I wrote the archive about the difference in coefficient of linear expansion between SS and aluminum. It doesn't matter what any manufacturer says, the laws of physics don't change. The colder temps automatically detune ANY rig, provided the mast is aluminum. If you want to decrease the rig tension beyond what mother nature is doing, then you will need to include the natural decrease in your calculations. I would ask any manufacturer if the recommended decrease that they are talking about includes the dercease created by the temp change.

 

[Jim]

Standard Rigging

I am with Don and Alan. Let it alone and it will slack itself. Loosen too much and you risk your mast to a big blow. It's not a guitar neck , it's a mast. My two cents. Regards, Jim

 

[Capt Ron;-)]

Learning Boating Never Ends

Ian, Good post, I knew nothing about this...learning all the time...

 

[Jeff Costa]

Rig Tension

I am unsure if you need to de-tension your rig, but I have a 1980 O'day 28 w/tall rig. When I bought the boat there were two indents one port and one starboard, just above the boot stripe and forward of the chain plates. It seems that the previous owner had tension on the rig grater than normal specs, to cause this I am assuming. As I stated the indents are just forward of the outer-most shroud, if you hear anything else please let me know.Jeff Costa

 

[Jeff Costa]

Rig De-Tension

I am unsure if you need to de-tension your rig, but I have a 1980 O'day 28 w/tall rig. When I bought the boat there were two indents one port and one starboard, just above the boot stripe and forward of the chain plates. It seems that the previous owner had tension on the rig grater than normal specs, to cause this I am assuming. As I stated the indents are just forward of the outer-most shroud, if you hear anything else please let me know.Jeff CostaS/V SALT SHAKEr1980 O'Day 28

 

[David11054]

We leave it

There is no "wear" involved in leaving the rig tensioned. And a tighter rig _decreases_ the wear and tear compared to a loose rig that lets the wind move the mast around through the winter.Given that the differential response to cold does loosen the rig a little, we leave ours at the same tension through the winter. We still carefully check tension on recommissioning, however.DavidLady Lillie

 

[higgs]

Never have done it

I have have been storing my boats in WI winters for 30 years - probably 20 of those with the mast up, have never detuned and have never had any problems.How much does the mast and rigging actually shrink? It seems to me that unless your rig is really tight, it can't be that much.

 

[Alan]

The coefficient of linear expansion for aluminum is about twice that of SS. To give a rough idea of the change in length, a mast(aluminum) will shrink about .75" if it is 50' long and the temp change is 50* (70*-20*). The shrouds will shrink about 1/2 that amount or .375". This will mean that the relative change in shroud tension would be the same as a .375 loosening of the shrouds or 3/8". This will reduce the tension in the rig by about 25%.

 

[higgs]

shrinkage

I am surprised that a mast will shrink 3/4 of an inch.

 

[Matt]

something else???

Maybe the indentions are from trailer storage (or stands) rather than the compression from the mast/stays. We have a donated club boat (san jaun 24) that had a couple of indentions in a similar spot that were the result of being stored for many years on a trailer with the keel plate lowered. The indentions were from the bunk rollers on the trailer. Fortunately they "popped" into original condition after being in the water again.

 

[Alan]

shrinkage

If you don't believe my math, do it yourself. The coefficient for aluminum is 24 X 10 to the -6. SS is 12 X 10 to the -6. All you need to do is plug in the temp change in your area and the length of your mast.