Reducing Mainsail Size Foot or Luff?

savageseadog

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We've been thinking of reducing our mainsail size to reduce our IRC rating. The problem we have is the reduced crew number means we can handle less power so above 12-15 knots we aren't using the area we're rated for. What opinions do we have regarding the idea and should we lose the area on the foot or the hoist?
 

olly_love

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We've been thinking of reducing our mainsail size to reduce our IRC rating. The problem we have is the reduced crew number means we can handle less power so above 12-15 knots we aren't using the area we're rated for. What opinions do we have regarding the idea and should we lose the area on the foot or the hoist?

For half the price of your IRC you can get a trial Certificate. if the reduction only gives you a few points then may not be worth it ,

the main things to do first to get it down are have the boat weighed and measured as most are over weight.

reduce SPL

Reduce LP or HSA
 

flaming

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Mainsail area normally has a big effect on rating. We once dropped 2 points just by remeasuring an existing sail and discovering it had shrunk a bit.

I'd talk to your sailmaker, but I'd expect reduction in foot length to be a better option.
 

savageseadog

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Mainsail area normally has a big effect on rating. We once dropped 2 points just by remeasuring an existing sail and discovering it had shrunk a bit.

I'd talk to your sailmaker, but I'd expect reduction in foot length to be a better option.

I was pretty sure a reduction in foot length was the way to go.
 
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Either raise the tack, thus lowering the clew or if you cant do that then cut the head down into a fatter head. Both quite easy to do and much less work than shortening the foot.

Ill find some photos in the morning of a few I have done to give you an idea
 

flaming

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Either raise the tack, thus lowering the clew or if you cant do that then cut the head down into a fatter head. Both quite easy to do and much less work than shortening the foot.

Ill find some photos in the morning of a few I have done to give you an idea

To be honest I assumed he was talking about ordering a new main with different dimensions, rather than cutting down an existing sail.
 

savageseadog

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To be honest I assumed he was talking about ordering a new main with different dimensions, rather than cutting down an existing sail.

Yes. I might try a second hand sail of the approximately the right dimensions first. I wouldn't go for a cut down.
 

Birdseye

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I always thought that most of the drive in a sail was in the first few feet of the luff. Thats why wingsails work well.
 

Beelzebub

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Whilst reducing the foot of the main undoubtedly has rating benefits, light wind performance does suffer. Having sailed on two boats that went down this route, one did OK and the other just became stuck in anything under force 3.
 
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