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Sails and rigging

Downwind head sails for the Pacific Messages in this topic - RSS

Dick
Posts: 330


10/24/2016
Dick
Posts: 330
Hi all,
I am curious, in reading the whole report, why all the worry about the rig integrity: either furling gear, forestay or backstay. It takes so little apparent wind speed to get a boat up to a decent boat speed downwind (compared to upwind loads and shock loading from bashing to wind) that I would not think worrying about damage to the rigs components would be a big deal. I find most boats allow themselves to become overpowered downwind and that decreasing the sail area significantly usually results in far easier motion, greatly reduced loads, less anxiety about broaching (and other downwind disasters) while only losing a few tenths of a knot boat speed.
What am I missing?
Dick Stevenson, s/v Alchemy

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Dick Stevenson, s/v Alchemy
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archive
Posts: -1


10/24/2016
archive
Posts: -1
I tried twin 140 's on the foil from Gibraltar to the Canaries. I have only one pole so used the boom! whilst not perfect it was a very easily handled rig for three on a 42ft boat.

I have now bought a light weight twist sail which will sit very comfortable 'inside ' the genoa when upwind.

Now sorting out a second pole and car!

Very good downwind rig.

Tony
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bwallace
Posts: 50


10/3/2016
bwallace
Posts: 50
I have read all the above with interest. No one has mentioned the "Twistle rig". Two Genoas of similar size on the same furler, (twin track) with both poles going back to a free universal joint held in place by an uphaul and downhaul. This takes out most of the rolling that is transmitted to the hull through the mast. No problem with the foil taking two sails, but if one is not happy and is worried about strain on the furler track leave one turn of sail on the foil. This rig is great for a long downwind passage. We crossed the Atlantic all the way from Canaries to Martinique in 2007. When the wind increased we just furled the sail more, and the main sail stayed inside its cover on the boom! Wind vane steering made for an easy and fun voyage.

Brian Wallace B)
s/v Darramy
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Simon Currin
Administrator
Posts: 774


10/2/2016
Simon Currin
Administrator
Posts: 774
I took the following posts from the OCC Facebook Page:

Toby Norman
19 hrs
I 'm in need of advice please. We have the ability to run twin headsails having recently renewed our 140% jib. Essentially my concerns are putting excessive load on the forestay running the two jibs through the twin tracked proful roller reefer. I have a single pole to fly the windward sail but I 'm concerned with the loads with such big sails over a Pacific passage. Neil McCubbin Peter Whatley and Colin Speedie your advice much appreciated.

Russell Frazer We came across the Atlantic Westbound in that exact mode. It was a really great set up! Yes we rolled and snapped along and I worried about the head stay too. However years later removing the wire and taking the pro furl apart for routine re wire it was found to b just fine.

Toby Norman Really pleased with the pro furls. It 's just huge stress on the stay which concerns me. The profurls like many have the second tracks which I assume is for running twin sails.

Linda Lane Thornton We sailed across both the North Atlantic and the Pacific with two headsails on the twin-grooved forestay of our 20 year old Harken furling system, where both sails could be reefed simultaneously. When the wind shifted onto the quarter, the windwarrd sail could be mo ed to the leward side inside the leeward sail, and again both furled together. An effective rig and no issues with fatigue: that came much later.

Chris Mortimer We thought about this, but for the same reasons decided to goosewing across the Atlantic with prevented mainsail and poled out 140% genoa. Both could be furled from the cockpit, without removing pole and preventer. During the day we flew a gennaker but for safety took it in at night.
Like · Reply · 14 hrs · Edited
Toby Norman
Toby Norman We did exactly that for the Atlantic and made a fast safe crossing although chaffe was really high with the rolling

Peter Whatley Hi Toby this is an interesting question and worthy of consideration and debate as it is sure to produce different views.

We carry a number of coloured sails but the problem in using them when deep sea is the rolling and subsequent moving of the centre of effort that causes more rolling. So they tend to stay in the bag and come out for local sailing. Our solution has been to use twin poles with a 110% genoa on the furler (Profurl) and staysail hanked onto a removable stay close to the forestay. The staysail is not big but is efficient. The genoa is rolled in a bit to keep it taut and this helps prevent chafe both of the sail and the sheet that we feed through the pole end. We have found it better to hand the main completely when the breeze is steady as this prevents the risk of damage and chafe.

Having a clean bottom helps keep the speed up.

We did contemplate having two sails on the furler using one halyard but somehow we couldn 't quite bring ourselves to do this although I know that plenty of people are happy with this arrangement.

When things get a bit exciting (vicious squall with extra rain) we furl the genoa leaving the pole in position (fore and aft guys essential) and if the staysail proves to be a bit much then we just dump the halyard and the sail collapses. We don 't dump the sheet.

A second furler close to the main forestay is quite popular and a system much favoured by designer and past Commodore, the late Mike Pocock.

I have heard many stories of pole tracks being ripped off because most boats have a single track on the centreline. I 'm sure you can envisage the geometry. We prefer twin tracks either side of the centreline. So, to conclude my preference would be for independently rigged sails each rigged firmly with its own pole. I think the Profurl is a strong unit as the section is big although I have always been a bit concerned about the sloppy fit plastic bearings but they seem to survive.

I have no doubt that others will have their own views and experiences that suit their boat.

Isn 't it a great facility within the OCC to be able to ask these questions and get responses from such a wide audience of sailors. It is one of the benefits that I am always extolling to prospective members.

Hope this helps. Fair winds

p.s. New boat coming on a treat! Will send photos.

Toby Norman Thanks again Peter
Alex Blackwell Hi Toby Norman
I would contend and went out from the premise that it is not the forstay we need worry about (bar the attachment points. Much rather it is the back stay that is to take double the load. So when we did fly two headsails, in our case a gennaker and a yankee, we made sure our running backstays were deployed. As mentioned above, we also always reduced sail overnight.

Toby Norman Great point Alex Blackwell, always shy away from rigging them for some reason. Tend to only use them if using the staysail in strong wind which to be fair is rare as the jib alone is normally more than enough drive

Emerald Sea Aroundoceans Toby Norman. You are significantly increasing load into the complete furling and pole system. Ultimately only the manufacturer understands its design limitations and you 'd be best to address this with them. We have done similar with our Facnor and they replied with a reduction in sail area in increasing wind conditions.

Colin Speedie Hi Toby, my concern would be slightly different. 140% is big and with a standard length pole I would partially roll the sail to avoid having a bag in the sail that would tend to generate rolling. And that 's something that cannot be done with twin sails...See more

Peter Morley Personally I 'd want a pole for both sides for sailing relatively direct downwind and/or light winds with rolling, unless you have experience with yours that suggests it 's not needed. My system is something similar to a twizzle rig. I am pretty cautious on deciding to reduce sail as both are hank on. Should also admit I haven 't actually set it in years, great system but has drawbacks for single-handed coastal sailing!

Toby Norman Fantastic advice chaps, thanks so much to you both. Very much respect and value both of your opinions. Colin agreed, 140 does carry a baggy sail even with our huge telescopic pole at full length, granted a reef helps. We have been offered a second huge pole for a very reasonable price but I 'm reluctant based purely on deck space for a second pole that might never get used. I had thought of a small pole for the stay sail instead which might be a compromise, maybe attached as a second pole below the main spinnaker pole. That said, our stay sail is small and requires running back stays.
It 's difficult trying to work out in advance a suitable rig for a ketch to cross the Pacific. I guess I need to play around for the first few days.

Thanks again for your thoughts. Hope your both well and Peter, would love some updated pictures please!

Colin Speedie Toby, a short whisker pole might be fine, or even rig a block on the main boom (with the main stowed) for the staysail. That way you can still reef the genoa at will easily and the staysail won 't collapse. 'Poor mans downwind rig ' it 's sometimes called but works fine - just the usual necessity to watch for chafe. And I 'd just stow the mizzen on a ketch.

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Simon Currin
S/V Shimshal simon@medex.org.uk
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