New furling jib

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SeaHawk215 SeaHawk215
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New furling jib

Hi

I have been given a furling jib with a nearly new sail but it is too long. Has anybody raised the forestry higher up the mast, it looks like there is another fitting at the top of the mast but have not lowered the mast to have a look.

Thanks

Ben
Perry Perry
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Re: New furling jib

Ben

I’d avoid that for a couple of reasons. First off the strength of the mast relies on the tension between the lower shrouds and the forestay. If you move where it’s connected then the mast bend changes and you weaken the mast strength. Might be fine, but might break.

Also, a larger foresail puts way more pressure on the bows, and will lead to much greater leaning when you are closehauled.

If I were you, I’d get a bit trimmed off the curling job foil and a bit trimmed off the bottom of the sail. Any decent sailmaker should be able to do that for not too much money, and then you have the right size sail!!

Let us know how things go

Perry
GregSeaHawk GregSeaHawk
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Re: New furling jib

In reply to this post by SeaHawk215
Hi Ben,

Judging from the photo on your Introduce yourself post, your mast is the standard SSS mast and unless there some customisation has been (your photo doesn't show the top of the mast) it will be the same as that shown here:

SSS Spars top of mast
The reason I took the photo from the rear is because there are no fittings on the front of the mast.

I'd agree with Perry's comments on the necessary support of the mast. Checkout the other pictures of the SSS mast at:
https://www.seahawk17.org.uk/boat-description-rigging.php#reedcraft

I'd also back Perry's advice and have the sail trimmed to fit. If you're thinking of converting to a masthead rig then you really do need a mast designed for it. There are one or two owners who have done that, most probably because they had a mast catastrophe and cannibalised one from another boat. Here's one example:
https://www.seahawk17.org.uk/boat-gallery-eu-german.php
Greg Chapman
GregAfloat - My Boating Biography
hardbob hardbob
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Re: New furling jib

Hi Greg, Perry and Ben

I am also considering to add a jib furling system to my rig. It is a Nemo Wonderfurl TR model (if I can get the last missing pieces, i.e. 4.5 meters foil). It will entail a few modifications. I will have to replace the forstay since it has to be a minimum of 4 mm wire for that furling system. This change I imagine will be fine for the rig. A stronger forstay and one that I can tighten more than the current, will also mean that the other wires can be become more tight. Furhermore, to ensure a suitable angle from halyard to the top swivel, a halyard block is to be added approxitmately 15 cm below the point where the forstay is fixed to the mast. On a fractional rig like the Seahawk, I guess this angle could also be ensured by adding a new fixing point for the forstay approximately 15 cm above the current internal halyardblock on the SSS mast?

Going back to the input from Perry against modifying the fixing point for the forstay, does that also include a minor modification as the one considered here? I guess the new fixing point would be about 10 cm above the current one. I was thinking that a slight increase on the forestay (+ the furling jib system) could be at benefit in terms of the sails that can be fitted. Reading Perry's input, I am now considering if adding a halyard block 10 cm below the current internal block will be a better choice. This is how the right angle from halyard to topswivel is typically ensured.

Best regards, Thomas
Perry Perry
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Re: New furling jib

Hi all

Okay, so minor modifications are less likely to be a problem than major ones. The aim of the combination of forestay and jib are to bend the mast slightly forward at its centre section so as to give some ‘belly’ to the mainsail.

However, I would point out that with a jib the size of the Seahawk, the main point of furling is to put it away, not to reduce sail. It’s so small that you are v unlikely to use a half rolled jib to reduce sail, so don’t need a foil to keep the luff in shape.

As such, I’m not sure I’d even bother with a foil. You can just use a furler and a wire foresail luff, and that will furl no problem. Then you are just using the forestay to support the mast, not even to hoist the jib on. Look at boats like dart 16 catamarans to see what I mean. Holt and rolston both sell furlers to do that job.

Happy to provide more info if you need

Thanks

Perry
SeaHawk215 SeaHawk215
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Re: New furling jib

Thanks for all your replies, after looking i think you are right in having the sail adjusted to fit.

http://www.bartonmarine.com/tech-info-jib-furling-fitting-instructions.asp

You may also be right in just a top and bottom swivel as the link above as i assume you mean as the foil may be too big, i also assume you need a wire between top and bottom swivel?
Perry Perry
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Re: New furling jib

Spot on! A foil is a flat tube that the sail can wrap around but is only needed to keep the leading edge shape if you are furling to reef.

And yes you need a wire, but it’s usually built into the leading edge (luff) of the sail already. You can use that.
Marsh Marigold Marsh Marigold
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Re: New furling jib

In reply to this post by hardbob


We have a very simple furling system and it works well.  I could post some close ups but am not sure if I can post more than one picture at a time (Greg?)
SeaHawk215 SeaHawk215
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Re: New furling jib

Great thanks, do you have a picture of it unfurled?
GregSeaHawk GregSeaHawk
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Re: New furling jib

In reply to this post by Marsh Marigold
You can add as many pictures as you like in a single post.

I recommend leaving a blank line between each picture. You can always check the appearance by using the "Preview Message" but to check how things appear before clicking on "Post Message"

In most cases it is best to centre the image and not try to have the forum adjust the size. There's much more on images in the FAQs Section.
Greg Chapman
GregAfloat - My Boating Biography
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