Rig & Sails
revised April 2016
First and Important! – Read your riggers advise and warranty policy.
Seldén e.g have an excellent manual
“Hints and advise on rigging and tuning of your Seldén mast”
which can be downloaded from www.seldenmast.com and it’s an essential part of any yachts safety library.
Moon has a masthead/cutter rig with two straight spreaders, baby stay, double aft lowers and running back stays. To keep the cutter tensioned without the running back stays in calm seas, there is a diamond. Back stay is hydraulic tensioned and the Vang has a gas spring and 8 geared rope for tension.
The mast is manufactured by Holland Spars Handmade Masts in Ternheuzen, painted white and very strong.
The profile has optimised thickness across and weigh 10 kg/m, IY 1062 cm4 and IX 2595 cm4. Two halyard winches, Andersen ST46 bolted on to thick welded plates. Stays and shrouds are stainless 19 thread 10 mm wire, lower aft is 12 mm. Top shrouds that are 10 mm and made from Dyform wire to give similar flex as the shorter intermediate shrouds made by normal 19 thread wire.
Running back stay consist of a single 14 mm Dyneema ropes. All running rig and sheets are made from SK78 Dyneema from Robline, 12 and 14 mm Admira 7000 Racing. 12 mm in all sheets and halyards including the topping lift to be able to used as a halyard for the anchor rider sail.
Both head sails has Harken furlers and the main sail has “old fashioned” slab reef at the mast.
All sails are made by Albatross in Gothenburg and made out of DYS clothe from Dimension-Polyant.
Yankee 48,3 m2 and Cutter 25,8 m2. Flying a Yakee and Cutter means that the big headsail is not bigger than the 132% genoa on our previous 37 feet boat, keeping winches and other equipment to a “normal” size.
Andersen ST 52 (same as the old boat) for the Yankee and Andersen ST 46 for the Cutter.
Both sails are cut to clear the lifelines and stanchions and to give a clear view ahead. The view is important but even more important are the less chafing and less forces on sail and rig from sea water not reaching a high cut head sail.
Mainsail, 45,3 m2 and are equipped with five full length battens. Two reef, positioned as 1,5 and 3 reef on a three reefed “normal” main.
With two not reefed head sails we reef the main already at about 16 knots headwind and then the second reef before we adjust the head sails.
The head sails are reefed in the following order. First we furl the Cutter completely. Then four turns on the Yankee when a full Yankee is too much. If increasing wind we furl the Yankee and out comes the Cutter. Two reef in the Main and full Cutter gives Moon a balanced and very efficient sail area in head winds from near gale and up…
The main sheet is on a track at the aft edge of the hard dodger with a six geared sheet through a block with a cleat at the aft end of the boom. It’s not very common solution, but very efficient as you can use your body weight when you pull the rope. It also leaves the cockpit clear from blocks, tracks and travelers.
Gybe preventer, a 12 mm Dyneema, is maneuvered from cockpit to a block at the bow and then back to the boom, and has double function as downhaul for the whisker/spinnaker pool. All other lines/ropes to the main are handled at the mast.
On our 37 feet boat with a solent stay we had a Jib really close to the Genoa, not to be used together with the Genoa sailing to windward, but extremely efficient as a stay sail going down wind. The Cutter on Moon is very good together with the Yankee in head winds, but too far away from the Yankee to give the same efficient stabilizing effect sailing off the wind. We have some improvements to try out there…
Earlier Moon was equipped with a spinnaker pool stored at the main boom, damaging the paint and difficult for one man to handle on a moving deck to say the least.
Today we have the spinnaker pool permanently attached to the traveler on the mast and parked at the outer end to a bracket on deck just behind the baby stay. It’s parked parallel and close to the stay. When using the pool it is fixed at the mast end and the other end is carried by the lift and easy to handle even in rough conditions.
Baby stay is compared with lower forward stays very well for the cutter, but it is a pain when using a spinnaker pool, limiting the angle forward that the pool can handle.
It seems that most things in sailing are about compromises!
Information below is general for most rigs and are mostly from Lindisfarne.
Link to Detail Album – Drogue, Rig & Sails
The prudent cruiser has to consider the additional demands that will effect the rig, sailing full time on the oceans, compared to “normal” coastal recreational sailing for the normal lifetime of a yacht. The latter is probably closer to the design criteria!
– Design – Consider the effect of fatigue. “Standing rig not older than 10 years” is often a demand in insurance policies, not without a good reason.
– Pre tension – Important! e.g minimize fatigue, prevent deformation and improve sail performance.
The pre tension of the cap shroud is 15 – 25 % of the breaking load of the wire, the lower figure for masthead rigs with straight spreaders, and the higher for fractional rigs with swept spreaders.
– Align chain plates – rigging screws – shrouds – and attachments to the mast. If aligning is not possible, toggles must be used, not to introduce extra fatigue loads.
– Vertical spreader angle have to be 6 degrees up from the horizontal plan.
– Adjust newly oiled rigging screws with a minimum of load.
(have the backstay tensioned, and when adjusting under sail, tension leeward rigging screw, never windward )
– Use Chrome bronze rigging screws (consider upgrade one size) to minimize fatigue and the risk of yield in the threads.
– Consider using Sta-lok/Norsman end terminals on wires. Easier to replace a broken wire in a remote place.
– Swaged terminals.
Sensitive to misalignment (fatigue) Difficult to get new done everywhere.
– Chain plates. Solid and strong, watertight and no forces in hidden threads (trough deck).
– Finally have the exact diameter of the holes for the clevis pin to the rigging screws and other attachment in the rig.
Be very careful with the alignment between chain plates and rigging screws.
If an angle occurs it’s absolutely necessary to use a toggle ( right size) between the chain plate and the rigging screw to avoid pre mature failure (fatigue).
– Check before every passage – the surface of the aluminium mast around every spreader, shroud attachments and fittings. Halyard sheave boxes, slots and cleats. Hooks and bolts in the head box, split pins secured, wires and swages (or other end fittings).
– Furling mast – furl the main keeping some resistant in the outhaul, straight mast to keep the profile tensioned.
– Have the backstay marked at 1; straight mast (to furl the main), 2; ok tension to furl the head sails and “normal” sailing, 3; max allowed tension in the fore- and aft stay.
– Furl the head sails with some resistant in the sheet and with enough tension in the forestay. Avoid flutter and let the sheets continue a few turns around the furled sail.
– When on anchor, allow the sheets to run back along the deck to minimize “sailing on anchor”
– Secure the furling lines. A halyard clutch on deck close to cockpit is perfect and it even allows you to furl safer. If you loose the furling line while furling, the head sail “normally” folds out and rips in strong wind.
Furling through a locked clutch, this never happens. Much safer and you can even rest furled halfway!
– Avoid having the mast pumping back and forth in heavy seas. (check stay, inner fore stay and tension the back stay.)
– Never allow the forestay and cutter stay/solent stay with a furler to swing. Have them tensioned enough at all time to avoid a lot of various damages on the furler and it’s fittings. Make sure your backstay tensioner is tensioned enough!
– Never let the top of the mast get a negative bend due to heavy load in the forestay or reefed mainsail. Use Back stay tensioner!!
Sails on Lindisfarne
We only fly Dacron sails on Lindisfane without any other fibres. The main and jib had done some 32 thousand miles and the genoa 25 thousand until November 2008.
Wear and tear are obvious, especially the threads are damage by the UV-radiation. But still it’s a safe material that last longer than until it no longer “sails”.
– Lindisfarnes rig is a masthead rig with two straight spreaders, keel stepped mast, separate intermediate shrouds, double lower shrouds as a “standard” rig. All wires are one size up (7 to 8mm, 8 to 10 mm and rigging screws are 3/4″ instead of 5/8″ and of course chrome bronze. Decision taken after having considered increased fatigue loads during full time cruising around the world for ten years!)
– We have even upgraded the rig with running backstays and an inner forestay. On the latter we can fly a storm jib.
– Furling main with four 2,5 m long vertical battens. New since 2009, with the same batten system and made of Dacron, by Doyle in NZ.
– Genoa 1,3 on furling forestay (Furlex 300) on the extreme bow. New in NZ as above.
– Self tacking jib 300 mm behind the forestay (Furlex 200). New in NZ as above.
We can’t tack with the genoa without furling it completely and then let it out on the other beam. This is because of the self tacker on the solent stay just behind the forestay. But having a blue water hull, Lindisfarne turns gently through the wind, so in fact we have almost time to furl and unfurl so it doesn’t slow us down much. On the plus side is the “lack” of wear on the genoa because no chafing on stays and spreaders and no flutter thanks to the furling (and again; some tension in the sheets during furling). The slow genua tack is more than well compensated by the advantages of having a self tacking jib.
The jib is of course a splendid headwind sail, but it is a very efficient down wind sail as well! We use the jib as a staysail, firmly sheeted between the main and the out poled genoa.
Not wing-on-wing as a lot of boats fly headsails. Our jib closes the gap between main and genoa, using the strong apparent wind across the boat in front of the mast when going down wind.
Two things happen.
– The speed increase because the sail configuration is greater and use wind that otherwise would have just “passed by”. But maybe more importantly, because the jib uses the wind across the fore deck and is firmly sheeted, the boat leans a few degrees to leeward and “stays” there.
– No more rolling when Lindisfarne is running with the wind!!
Of course in very light wind and confused seas there is not enough wind to stabilize.
Thanks to the wind pressure from the jib (back into the genoa), we fly the genoa poled out all the way up to 100 degrees apparent wind. Saves us a lots of work on deck when the wind is in shifting conditions (often found in light wind in the trade winds).
We use the whisker pole with three lines attached to the end fitting other than the head sail sheet. The lift to keep it up, the downhaul to keep it down and a third line aft to prevent the whisker pole from following the genoa forward when furling.
The latter is very important. If you allow the pole to go forward when furling, the genoa can’t be furled completely, because the whisker pole is much longer than the distance between the mast and the forestay, letting the genoa flutter until the whisker pole is released.
Furthermore, if you furl in at night because of strong wind, you can leave the whisker pole with it’s three lines in position until dawn. Much safer and comfortable (the wind might even have changed by then!)
One disadvantage with our two very tight placed headsails is that Lindisfarne tends to sails when on anchor. To prevent that we fly an anchor sail (anchor rider) on the backstay, using the topping lift (dyneema) as a halyard.
Works perfect. No jerking turns at the end of the chain when she “tacks”. It’s merely a light turn with her stern when the sail catch the wind and presses the stern through the wind, in opposite to when the chain “pulls” the bow through the wind. Much more comfortable and perhaps more important – less stress on the chain and anchor. Works good even on a mooring.
The need of running back stays and inner forestay became evident one night in rough condition between Shetland and Norway. We didn’t like the way the mast at the upper spreader moved back and forth.
Today, going out with the tide, into the swell is possible without any excessive movements in the mast thanks to those extra stays.
The storm jib attached to the inner forestay of course demand running back stays, but that came later, using the advantages with already having these stays. The main reason for upgrading the new mast with these stays was to stabilize the mast at the upper spreader.
We have even changed the chain plates. Two reasons, leakage and threads through the deck, not possible to inspect. The new ones are simply a plate, similar to the old ones below deck but continuing through deck including the hole for the clevis pin for the rigging screw. Using the “old” bulkheads and holes below deck. Material upgraded to 2205, high strength stainless steel, and thanks to that we have been able to weld watertight plates, bolted through deck. The new plates are angled to their shrouds attachments on the mast, both lateral and longitudinal.
The back stay, inner forestay and cutter stay have also new “chain plates” described more in detail in the photo album.
When changing all the chain plates, we took advantage of the opportunity and installed a lightning protection.
All stays and shrouds are connected to keel bolts via 16 mm² cabling between chain plates and keel bolts. The mast has a separate cable to the keel. The system will probably not protect our electronic equipment, but it will hopefully save us and the boat even if we have a direct hit.
Link to detail albums-