Quick release - regulable forestay

[J.Teixeira]

Quick release - regulable forestay

I just posted in Mac Mods this mod

This is a very standard mod...

To make it easy to remove and insert the furller pin wen lowering and rising the mast i inserted a bar between the normal support and the bow roller.

But when using it i did found out another interesting utility.

Bi moving the position of the furller pin along the pierced bar (i don't know the name in English)

It makes possible to move forward and backward the head sail.

That helped a lot when tuning the sails balance.

Making possible to control almost perfectly problems like weather helm



Is this crazy?

Or a good idea ?

Best regards

JT

http://www.macgregorsailors.com/modt/in ... ?view=1106

PS: Please check mi english on the mods page

[Nautek]

Not a silly idea however I would have doubts about the strength of the fitting as they are not made to be used in that position
It would also make it difficult to carry an anchor on and use your bow roller for the anchor. I carry my anchor there permanently.

Has anyone used the stay adjuster in the link below on the backstay rather than the forestay??
Installation would be easier and you would not be pushing the furler further up the forestay.

http://www.kellyhansonmarine.com/apps/w ... how/115896

Allan

[J.Teixeira]

Hi

I have a Harken system in the back stay.

But it serves a different purpose.

Bends the mast and controls the bag (curve) of the main sail.

Low wind - release the back stay = more bag

High wind - push the back stay = less bag (flat sail)

Mi picture is horizontal only but the system does not interfere with the anchor roller. (i reduced a bit the size of the rubber roller.)

About strength i used 2 U shape bars one facing up and one facing down. One inside the other...

A force big enough to brake them... I think that first everything would come out from the GRP...

About your suggestion the problem with that system that you show is that in mi boat is that it would rise the sail to high and it is already to near the limit at the mast. (It is a UK Sails high quality 130 genoa)

But i maybe wrong... But i don't think that it is a good idea to move sails up in a Mac.

Mi doubts are more about moving the sail forward to control weather helm problems wen tacking...

JT

[craiglaforce]

I had the same thought that the lifeline adjusters will not be strong enough, but I guess you will find out by trial. They bend rather easily.
Sail trim is usually accomplished by reducing the mast rake angle. (tightening the forestay turnbuckle and loosening the shrouds a bit if needed.

[ALX357]

this mod was described in great detail somewhere previously but my quick search could not find the threads, ....

the adjuster serves as an adjustable extender, and a leveraged tensioner for the furler or forestay. It is actually as strong as the original attachment, because it uses a the second tang hole addtionally, vis. back-up attachment, and the adjuster plates are doubled, one interleaved in the other, with added pins. I have sailed with this set-up for 4 years now, never any problems, no bending or twisting.

[Indulgence]

Y'know what drives me nuts?
You see these really nice doubled up stainless steel adjusters,
solid pins, ring dings. Beefy looking setup, no question.

But then you look at the base plate and the whole thing appears to be factory mounted
to the deck with what looks like two pop rivets. I look at mine frequently and
wonder when it's going to let go. I'm sure the designers knew what they were
doing but it's always struck me as a weak point in the rigging. I intend to attach
a cable from the furler to my anchor roller bracket this winter so when the thing does
let go there's a backup that will prevent the mast from coming down on my head.

Just my 2 cents,
Laurie

[Highlander]

Laurie

What you are looking at as you describe I think is just the face plate on the shroud & forestay anchor plates that are riveted to the deck all they do is give the deck slot for the anchor plates a clean look & cover up the slotted holes in the deck & are sealed with 5200 also to prevent water penetration the shrould & forestay anchor plates are all anchored with 2 - 3/8 bolts in the hull

J

[ALX357]

Yes its a very strong attachment below the deck to the hull, bolted with two large bolts, on the starboard side just aft of the fiberglass reinforced gusseting of the bow. You can see one bolt's head from the outside of the hull, below the deck-to-hull joint directly in line with the tang and forestay line, and from the inside on 2000 and later X boats by crawling forward on your back in the V-berth and looking up into the boat's inner hull there.

[J.Teixeira]

Hi

I mi boat i installed a triangular SSH plate inside holding all the bolts in the bow.

The factory system did not look very strong...

Sorry but no pictures of that (one of this days...)

- - - - -
ALX357

Mi mod was inspired on yours.

But I don't have available vertical space in mi forestay for that.

I also think that your mod seems to increase a lot the stress on the plate bi adding a BIG lever force to it... And "twisting" it...

That is why I did held the adjusters to the bow roller on the other extremity.

It seems to me that on a lever system both ends should be held to strong points

Another aspect of moving the furller up is that we are moving the entire Genoa UP about 1 ft and that is not very good idea in a MAC...

One interesting thing in your mod is the big "PIN". Where did you find it?

- - - - - - - -

craiglaforce

Yes ! But mi thing is just an experiment before making a REAL SST LEVER replacing mi old lifeline adjusters...

I am just trying to find a really good solution. I think this is the right path...

Another more "dangerous" thing in this Mod (mine and Craig) is that in high winds if we need to really push the furller cable hard... We may twist the entire thing... That is wi if I stay with this mod I will go to a really strong bar...

JT

[ALX357]

I wanted the furler Genoa moved up to give clearance to see forward under sail, especially when singlehanded sailing. The sail is about a foot higher, enough to see forward on the water, and allow the lifelines to attach to the upper rails of the bow pulpit. If the concern is about too much force applied higher, considerr that the Genoa is triangular, and most of the sail area is low, and if there is too much wind, then the Genoa isnt the right sail to have on anyway. The compromises were worth the advantages, to me.

Consider that on the mod I showed, the forces are pulling less than two inches forward of the tang, minimal added leverage, and twist -- and that there are two pins holding the adjuster to the tang. If either one fails, the other is still holding the adjuster.

The rear pivot pin of the adjuster in the tang, is actually a thicker shackle pin, with a fairly tight fit in the tang, and the forward pin with the large head is called a "quick pin" sold by Blue Water Yachts. I bought numerous ones of these quick pins, used in many places where needing a faster but secure way to pin and unpin things. You can drill a hole thru that large head and attach a wire to tether the pin and keep it from getting lost.

In high winds, the furler will be difficult to roll in until you head up and release tension on the sheets somewhat. It is comparable to trying to lower the main while on a reach.

[J.Teixeira]

About moving the sail up I agree with you, but in mi boat I can't do that because mi genoa takes all the length of mi forestay.

About the lever I it is in fact a small lever but I worry about the GRP and not the SST parts. It would be reasonable if you reinforce the bolts sport with a SST plate to enlarge the surface of GRP and reduce the pressure.

About the pins thank you for the information, i will get them. I am a costumer of Blue Water Yachts (I am very satisfied with their service) and the pins will be on next order...

About the furler... well... mi furler is very different from your's... It is much larger and as a higher lever power. In fact i can roll mi genoa in a tack, reach or downwind if necessary like in other boats I pull it with the winch.
And it works very well.

With the quick release lever i don't think that it's a good idea to do the same amount of force.

Mi Mod:
http://www.macgregorsailors.com/modt/in ... ?view=1106

Your Mod
http://www.macgregorsailors.com/modt/index.php?view=699

Reinforcement
http://www.macgregorsailors.com/modt/index.php?view=626

Othe lever...
http://www.macgregorsailors.com/modt/index.php?view=514

[ALX357]

J. ....

Your furler does look more sophisticated and heavy--duty, certainly. My boat has the usual USA equipment, SDI FLexible Furler. Your furler's actual drum which winds the line is not much bigger, from the photos you provide... so the forces would be comparable, but I would never try to wind the Genoa under pressure with a winch or capstan as you describe. That seems like inviting trouble, unless your furler foil is so stiff that it does not bend at all. With any bend in the foil, or deflection, the spin wobble would be greatly increased. No wonder you have concern about the tang attachment, and all the hardware. I'd like to know what most other Mac sailors think of this, whether they do the same as you - wind up the Genoa furler line under full wind pressure with the winch.

As for raising the Genoa, which on my boat also at the top of the forestay and can be raised no further up the wire, --- I just re-mounted, or actually added another ) jib-head hound ( the steel straps that hold the furler to the mast ) higher up on the mast.

[J.Teixeira]

Hi ALX

I release tension on the sheet to pull on the furler...

But in high winds (MAC high winds...)

With the genoa reduced to 100 % or less...

Sometimes I pull it with the winch slowly .

It gives me a lot more control.

About the Harken Furler: the perimeter of is core is more than 2X a CDI so it realy makes a lot more lever .

But also is ball bearings are more effective so it is possible the there is less lever force to it's base.

About the adjuster plates: They are doubled, one interleaved in the other, with added pins. You said that you have sailed with this set-up for 4 years now, never any problems, no bending or twisting.

But one thing I wonder is about the capacity of the lifeline adjusters. will they be really strong enough for this.

Can I really trust those things? Or should I make a more solid bar?

Because sometimes I go out to the sea and with 2mt waves and 25 knots wind the gear suffers a lot...

And sometimes those situations are common here (North Portugal) at the end of the day

Best Regards

JT