Our desired long-term sail plan

I’ve made some progress on where we want to end up in terms of a sail-plan that is efficient in a wide range of wind strengths and angles. I’ve also, hopefully, got to the point where we will be able to get sailing without having to buy any new sails to start with. After all we are starting with 12 sails!

Here is the original sail plan.

Sadly, our current mainsail is much smaller (it was made for the roller furling that had been added to the back of the mast), it also does not currently have slides for the mast track and it has no reefing points.

Our genoa uses an old Furlex roller reefing and the sail shape, especially when reefed is terrible as this picture shows (it should not be all baggy in the middle of the forestay).

Traditionally Rivals have a fairly poor reputation for speed in light winds (and a fantastic reputation for ability to keep going in very strong winds). When you look at the sail plan it isn’t surprising (very little in the way of light wind sails, all sails set within the forestay apart from the small symmetrical spinnaker). In the last 50 years there have been huge improvements in what is possible (such as Code Zero “genoas” and Asymmetrical Spinnakers) compared to carrying 5 hank on jibs of different sizes as shown in the drawing. The switch to a roller furling main and genoa will have increased easy of changing sail sizes but at great cost in efficiency.

We believe we can now do better, especially in front of the main mast.

So this is where we want to get to in the long term.

Mizzen: shorter boom to keep it out of the way of the wind vane self steering and also the solar panels. Fully battened (so that you can use it as a steadying sail without it getting damaged by flapping) and a fat head for more area. Two slab reefs – again useful for a steadying sail and as more options for small sails for storm conditions.

Main: Our new boom is a bit longer. So we will get a little more sail area without needing much roach. Will be taking advice (and be affected by price) as to whether to go fully battened for longer life but more expensive sail and potential need for much upgraded slides for the track in the main mast. 3 reefing points so we won’t have a trisail (with choice of either reefed mizzen or 3rd reef in the main we think we can go small enough and have a backup option). Will be loose footed. We will probably make a stack pack for it (although will keep it as small as possible as the boom is already quite high due to the wheelhouse so we want to minimise extra windage).

Staysail: Using a removable inner forestay (supported by new runners) we will have a hank on staysail makde of pretty heavy Dacron so that it can be reefed to be a storm jib.

Yankee Jib: Designed to work well as a typical cutter rig with the staysail. This will be around 100% with a relatively high clew (works well with the staysail and keeps it well clear of waves). This will be set using a continuous line furler. That means it can’t be reefed (partially unrolled). It is either all set or all rolled away. The continuous line furler has an anti- torsion stay in a pocket on the leading edge of the sail. This supports the front of the sail and passes the twist of the furling up the sail. Critically it will be set just behind the forestay (like a Solent ring). However, as it is not the forestay and does not have a structural anti-torsion stay, it can be lowered to the deck while rolled up when not needed. When at anchor in storm conditions it massively reduces windage and also surging from side to side if you have no rolled headsails up. With a normal roller furling genoa you have to unroll it in order to lower it (impossible and dangerous at anchor in strong winds). Plus sails that are not left up last much much longer. We might be able to save money initially by using a dyneema line instead of an anti-torsion stay and not having a furler.

Forestay: we need to have some work done on our bow roller to fit our anchor. As part of this we will move the attachment point forward a little so that the furler for the yankee jib will be clear of it. As the forestay will not be used for any roller reefing or roller furling sails it can be dyneema, the same as the rest of the rigging. I have designed a way to neatly connect a Dyneema forestay (and tension it/remove the gains in length from creep). The changes to the bow roller will include a guard to make sure that neither the anchor not the anchor chain can ever chafe against the dyneema.

Bowsprit for Code Zero or Asymmetric Spinnaker: we will fit a removable bowsprit such as this one from Selden. This is the key to significantly improving light wind performance. Using a second continuous line furler we will be able to fly either a huge Code Zero (flat sail for going upwind in light conditions where we would be very under powered at the moment) or an Asymmetric spinnaker (much easier to use than a traditional spinnaker although not quite as good for going directly downwind). We could save quite a bit of money initially by using “socks” rather than a furler for these sails.

Downwind extras: We have two more options for downwind sailing. One is a Mizzen Staysail (like an Asymmetric Spinnaker flying from the mizzen mast). The second should be good for sailing directly downwind in the fairly strong trade winds. That is to add a hank on jib (of appropriate size) to the forestay. The yankee jib can then be poled out on one side and the hanked on jib/genoa poled out on the other side. This is the classic downwind setup for ocean cruisers.

Getting there

So if that is where we want to be. Now we just need to get from A to B.

First task is all the chainplates and the bow roller so we can get the rigging sorted and the masts up.

Second task is to fit some form of hank to all our jibs/genoas (that won’t damage a dyneema stay) then we can use any of them on either our forestay or inner forestay (until they self destruct as some of them are original and so over 40 years old).

Third task is to fit slides to our existing mainsail (and possibly some reefing points).

This will allow us to get out and start sailing. Then we can prioritise new sails (although I’m sadly confident that the Bowsprit, Code Zero and Asymmetric spinnaker are a long way off at the moment).

The goal

This setup means we have enough choice of sail area through easy switches between sails that we don’t need any roller reefing (expensive, heavy, poor sail shape, high maintenance). All with 8 sails. So for example to go upwind

In light air: Mizzen, Main, Staysail, Code zero

First reduction: raise furled yankee and unfurl, furl code zero and lower. Left with: Mizzen, Main, Staysail, Yankee

Second reduction: lower staysail. Left with: Mizzen, Main, Yankee

Third reduction: swap from yankee to staysail. Left with: Mizzen, Main, Staysail

Storm: Get everything small: Mainsail with 3rd reef and reefed staysail (optionally swap main for reefed mizzen if it gives better balance)

Quick response to a squall: Lower the main and furl the yankee for a “Jigger” rig of Mizzen and Staysail (with reefing options for both).

Throughout the sail reductions we can reef the main and/or the mizzen to maintain balance. Very often to be very close hauled the mizzen will be lowered as it stops the main being sheeted in so hard.

Whilst it looks at first glance that there will be a lot of wet, dangerous foredeck work it is much easier to manage than the original sailplan where switching down a jib size would mean lowering a sail and going right to the forestay to unhank it (during which time it will trying to throw you overboard), then hanking on a smaller jib, swapping the sheets and hoisting it. In normal sailing there will be no need to go right forward (the yankee and code zero can be left up while furled until it is safe to bring them down). The staysail can have a downhaul so can be just pulled down to the deck and held there while you lash it to the rail – anyway it is much further aft. All the mainsail reefing will be done from the mast with the dinghy on deck providing a place to sit with a short lifeline so you can’t go overboard.

There are plenty of examples of Rivals being able to sail to windward in a Force 9. This sail plan should allow us to do that (with no illusions that it will be pleasant or comfortable) as well as go much faster in light winds.

Downwind: Again we have plenty of choices with easy twin headsails or the Asymmetric spinnaker plus the mizzen staysail for fun. Also the potential to use either the staysail or the mizzen sheeted in hard to reduce rolling.

Conclusion

We think we have a route forward that is reasonably affordable and ends up with a fantastic rig that will significantly improve both light wind speed and be far better in storm conditions compared to where we started and also compared to what was available in the 1970’s.

Next generation Dyneema Chainplates

This is a rewrite/reorganisation of this post (no diagrams yet) to, hopefully, make it clearer.

I think this is our 3rd generation of Dyneema Chainplate design. We think it is a significant improvement on our previous plans, yet realistically it might demonstrate some “Lockdown overthinking” so we are not ruling out variations on our original Synthetic chainplate idea in: Chainplates. We are going for a radical dyneema option.

All these designs and the process is for us to work out what we are going to do on our boat. We are happy to share to give you ideas for your own boat, but you need to check your plans with appropriate professionals as we can take no responsibility for whether they will work for you.

Although our previous design was significantly stronger than what our Rival 38 has had for the last 43 years, we have come up with big improvements (with a lot of conversations, especially with Simon T who has a Rival 32). Specifically these are:

  • More flexibility in deck position so they can be closer to the original chainplate position
  • More flexibility in the positioning on the outside of the hull to avoid rubbing strakes, coving strips etc
  • Simpler to build
  • Ability to have tie connections down into the hull (as Rivals should really have had)
  • Reduced possibility of chainplate lashing line chafe.
  • Reduced friction when tensioning the rig, making it simpler to tune

The previous design already met these requirements, but they are worth repeating:

  • A chainplate design ideally suited to synthetic shrouds, that eliminates the need for deadeyes and toggles to reduce the number of potential points of failure.
  • A chainplate that is much stronger than the original Rival implementation. See Deck repair question and note that Cherry Ripe had one chainplate fail on a recent transatlantic trip (their YouTube videos haven’t caught up with that point yet).
  • A chainplate that cannot leak, fully sealed with epoxy from the inside of the boat
  • A chainplate that could be fully repaired with parts that can be carried on board
  • A chainplate with minimal chance of hidden problems causing a sudden failure

We really need to define our own terminology so

  • Chainplate structure: the permanently bonded structure between the hull and deck that the Chainplate Lashing will thread
  • Chainplate Low Friction Ring: A standard Low Friction Ring that is the point to which the shroud is attached by a tensioning system.
  • Chainplate lashing: a light (we are going to use 4mm) dyneema line used to hold the Chainplate Low Friction Ring by being routed through the Chainplate structure. At a minimum the strength of the total lashing needs to exceed the strength of the original stainless steel shroud.
  • Tensioning system: we will be using a simple, thin dyneema line to lash the bottom of the shroud to the Chainplate Low Friction Ring. It will loop around multiple times to give a mechanical advantage and the end will be attached to more mechanical advantage (can be done with a winch or other means) to get enough tension into the shroud.
  • Knee: a shaped piece of material (we are going to use 10mm G10 or FR4) that ties the underside of the deck down the side of the hull. It helps stop the tension of the shroud on the chainplate structure breaking or distorting the boat shape.

Inspiration

The greatest inspiration for me was this video from Free Range Sailing “Our sailboat REBUILD begins ⛵💪 – Episode 157

They have an unusual situation for their backstays, when drilling the holes for the lashing they don’t go into the interior of the boat. A key design goal was to find a way to have a similar lashing for the low friction ring in places where it isn’t possible for a hole to go from the desk to the outside of the hull without going into interior. Also I didn’t want to have to add GRP matting to the outside of the hull. Finally, I was unhappy with the lashing as it relied on knots which is a problem with slippery dyneema.

Key Design elements

First we have a permanent structure to be built

For each shroud two plastic pipes will go through the deck (approx 40mm gap between them – scale as appropriate). On a Rival they can be in approximately the same place as the existing chainplate. They should line up with the shroud (following both the fore/aft and athwartships angles). Below decks they will curve to exit through holes in the side of the hull (still the same distance apart and level with each other). The pipes end approx 50mm above the deck.

A “backing” plate on top of the deck will provide reinforcement. It will make it easier to keep water out of the holes in the deck.

A “backing” plate on the outside of the hull will spread the loads and can be shaped to allow a very smooth curve for the chainplate lashing between the two pipes.

Inside the boat a knee will be fitted between the pipes. It will tie the deck to the hull and will extend down far enough to spread the loads over a large area of the hull.

Inside the boat the pipes will be encased in thickened epoxy. The will prevent any water intrusion. It will also create a single solid structure of deck, hull, pipes and knee to ensure loads are widely and evenly spread.

Second we have the connection for the shroud tensioning system

The permanent structure allows a lashing to attach a low friction ring above the deck. The shroud can be directly tensioned to the low friction ring using a lashing. As the low friction ring is lashed directly to the chainplate structure we eliminate a deadeye (with two thimbles) and a toggle – so removing several of single points of failure.

The chainplate lashing line starts at the low friction ring. Then it loops several times going through one pipe, across the outside of the hull, back through the other pipe and around the low friction ring. When there are enough turns for the maximum load the lashing terminates at the low friction ring.

Rather than use knots to tie the lashing at each end (which lose a lot of strength), terminate each end with an eye splice. These both loop over the low friction ring. Eye splices retain approximately 80% of the line strength. As all the loops of the lashing go over the “rim” of the low fiction ring the shroud tensioning lashing is held captive by the chainplate lashing. Therefore if the low friction ring breaks the shroud is still held captive. We can use eye splices rather than lashing knots as there is considerable flexibility as to how high the low friction ring ends up above the deck.

Third we have chafe and UV protection

The pipes extend approx 50 above the deck, their ends should be slightly flared. As they are slightly flexible they will automatically align (in a gentle curve) with the tensioned lashing so that chafe is minimised. The lashing can be easily inspected for chafe as it enters the pipes.

Extending the pipes above the deck also prevents dirt, particularly gravel, being washed into the pipe as this could quickly cut through the lashing.

The up-stand of the pipes allows a fabric sleeve to be secured at the deck so that everything from the shroud to the deck can be protected from dirt, chafe and UV. If the sleeve is a basic rectangle, with Velcro along it’s length, it can be easily removed to inspect both lashings and the low friction rings.

On the outside of the hull the backing plate can be filed and sanded to provide a smooth rounded route for the lashing to go between the two pipes.

Potential Upgrades

Rather than rounding/smoothing the backing plate on the outside of the hull a plastic pad could be added to provide a lower friction, smoother route for the lashing.

A pop-on plastic cover for the hull backing plate would protect the lashing as it goes between the holes. This would protect it from being damaged by docks, dinghies and the sun. It could be removed to inspect the lashing.

Instead of a single low friction ring for the chainplate lashing it would be possible to use 2. One for each pipe. The two rings would not be directly connected together above the deck but only by the lashing going down through the pipes. The advantages are a) alignment with pipes would be slightly improved as the lines from the pipes only come together at the bottom of the shroud rather than at the chainplate low friction ring. b) two rings so each has half the load c) each ring will only have half the number of turns of the shroud tensioning lashing, so a little less binding and friction.

Rather than a single chainplate lashing line, for each shroud, it would be possible to use several, each would act in parallel. The first eye splice on the low friction ring, through one pipe and back through the other before the other eye splice goes onto the low friction ring. Each “turn” of the lashing would be a separate line. If one line chafes through, it will be very visible but the shroud won’t suddenly become slack. This method would require very consistent splicing so that the lines are very equal in length (although even the small amount of elasticity and creep in dyneema will tend to equalise small differences over time).

Maintenance

All the key potential chafe points for the lashing are easy to inspect as it is highly unlikely that the lashing will chafe first in the hidden but smooth run inside the plastic pipe. Instead chafe will come first a) where it exits the hull, b) where it exits the pipes at the deck, c) where it loops round the low friction ring, or d) where something rubs against it.

Replacing either the chainplate lashing or the shroud tensioning lashing should be straightforward, even potentially possible at sea on the appropriate tack.

The most difficult task will be replacing a pipe when it wears through (although plastics such as hdpe should be very wear resistant). There are a few options

  • start with an oversized pipe so that a smaller pipe could be inserted through it later as a replacement (or have an fixed outer pipe and a floating inner pipe from the beginning)
  • coat the pipes in a mould release agent during construction so that they can be removed (some ingenuity may be required to ensure that they don’t move during use)
  • if the pipe fails then use a dremel with a flexible attachment to sand the route through the thickened epoxy so a pipe isn’t needed (a short length of pipe could be inserted at the top to provide the gravel protection).

Our construction details

We are hoping to use HDPE pipes, they should be low friction and hard wearing. However, the smallest I have found them is a 20mm external diameter. Maybe inserting a smaller sacrificial tube inside them would be a good solution or a different type of plastic?

I’ll use a heat gun to flare the top of the pipe to make sure the lashing doesn’t get damaged by the edge.

We will use the same dyneema line for both the shroud tensioning and the chainplate lashing to reduce the number of items we need to buy and carry.

Our main mast cap shrouds are the only ones with a chainplate that has a connection to a bulkhead. So some detailed thought will be needed (one pipe each side of the bulkhead?)

Our chainplates are in the deck and are close to the bulwark so the internal intrusion will be small. This solution may not be the right one if you have very inboard chainplates. In that case look at my original “padeye” design.

I’m going to use 10mm G10 for external chainplates and 10mm FR4 for the knees (I want first resistance inside the boat).

All holes in the deck and hull should be sealed with thickened epoxy (drill oversize hole, fill with thickened epoxy, when cured drill correct hole through the epoxy).

When drilling the final holes angle the drill to reduce the curvature of the pipes.

Our holes and backing plate in the hull will be a bit lower so that they are below the rubbing strake. You might want to miss things like cove lines.

Our cap shrouds have a piece of stainless steel bolted to the bulkhead that has a bent over top that sits under the backing plate. It has a hole fitted over the chainplate bolt and so when the nut is on the chainplate bolt is connected to the bulkhead. This will be replaced (on all our chainplates) by the FR4 knee. The top edge of this shaped piece of sheet material will be fitted to the underside of the deck and the long edge will fit vertically down the inside of the hull. In our case it will go down far enough to “hook” over the first horizontal stringer. The inner edge of the knee doesn’t have to be a straight line but can be cut away as a nice organic curve. The best place for the knee is between the two pipes. It should be glued in with thickened epoxy with good fillets along all the edges that touch the boat.

It is going to be tricky to fill around the pipes and knee with thickened epoxy so that there are no air pockets. My current plan is to create an enclosed space that I can fill (using thin plywood held in place and “sealed” with epoxy fillets). So the plywood is creating a kind of mould covering the pipes and part of the knee. Before I fit the deck backing plate, I will drill some extra holes in the deck and inject into them slightly runny thickened epoxy, until it is full to deck level. Once they are filled these holes will be covered by the backing plate. I can remove the plywood to confirm that the space has been properly filled.

The strands of the chainplate lashing are going to be under a lot of tension between the two holes on the outside of the hull. So it is vital that the route out of one hole and into the other is very rounded and very smooth. That transition from pipe to backing plate is going to be the key load point of the lashing, so it is vital that it does not chafe through here. We are going to carve a solid plate of hdpe (we will make ours as part of our plastic recycling work) that will sit on the G10 plate and be a very low friction, smooth, curved surface for the line. We will also fit a removable hdpe cover plate to protect the chainplate lashing from being damaged by docks or anything else.

Fitting the lashing

When you are ready to lash the Chainplate Low Friction Ring into place you have a choice. You can use a single ring per chainplate structure. Or for slightly higher cost you can use two. Having two improves the alignment of the chainplate lashing slightly and makes tensioning a little easier. If you use one then you need to size it so that the outer sheave can fit 3 turns of the lashing line rather than 2 (the number of turns depends on your calculation of loads and the line you are using – I’m planning to have 6 of 4mm, 3 per pipe, which is quite a lot stronger than my shroud).

Whether you use one ring or two your chainplate lashing needs a eye splice at each end designed to loop over the exterior of the low friction ring.

If you are using One Low Friction Ring then:

With the low friction ring above the pipes fit the eye splice from one end of the lashing. The other end goes down one pipe to outside the hull. Then in the other hull hole and back to the deck. Now loop it over the low friction ring and go down the first pipe again. From the hull outside return as before. Repeat for another loop through the chainplate structure. At this point the low friction ring should have one eye splice and two loops. Each pipe will have 3 lines through it. The outside of the hull will have 3 lines between the holes. Now slip the eye splice from the loose end onto the low friction ring (4 lines in total on the top of the low friction ring). While holding up the low friction ring up, tidy all the lines so that they don’t cross over outside the hull and as little as possible in the pipes. You can now use the tensioning system to connect the chainplate low friction ring to the shroud.

If you are using Two Low Friction Rings then:

With the first low friction ring above the pipes fit the eye splice from one end of the lashing. The other end goes down one pipe to outside the hull. Then in the other hull hole and back to the deck. Now loop it over the second low friction ring and return down the same pipe again. From the hull outside return up the first pipe and over the first low friction ring. Back down the first pipe, outside the hull and up the second pipe. Now slip the eye splice from the loose end onto the second low friction ring. While holding up the low friction rings up, tidy all the lines so that they don’t cross over outside the hull and as little as possible in the pipes. Each low friction ring should have 1 eye splice and one loop of lashing line. Each pipe should have 3 lines. Each low friction ring should have 3 lines all going into the same pipe. The outside of the hull should have 3 lines. To tension the shroud the tensioning lashing should start from one of the chainplate low friction rings, go up to the shroud and down to the other chainplate low friction ring. Continue to add more turns, alternating between the two chainplate low friction rings.

Tensioning the Shroud.

There are videos from Rigging Doctor, Tula’s Endless Summer and Sailing Zingaro showing how to tension using a lashing. Although, of course, we have our own ideas which we hope to test before too long.

Conclusion

We believe this design will create

  • a chainplate structure that you can easily build yourself.
  • something that you can visually inspect for wear and damage.
  • something with no metal parts that need to be fabricated, that can corrode or fail due to fatigue.
  • where you can carry all the parts to replace everything that works with the chainplate structure (lashing line and low friction rings, shroud tensioning line, shroud) even at sea.
  • a significant weight saving
  • a significant increase in strength on boats like Rivals where the chainplates are not very well connected to the hull
  • huge cost savings if your chainplates or turnbuckles need replacing
  • a very simple, strong, neat, light way of connecting dyneema shrouds to an older boat

Simplifying guardrail solar panels

From the beginning we have been planning Solar panels fitted to the guardrails. We have seen lots of boats with Solar Panels attached to the guardrails. However, as we are wanting to have zero fossil fuels we need more solar than most.

We have gone for Victron 175 watt panels for the guardrails and will start with 2 each side (as a centre cockpit we have more length available without blocking our view).

Later we plan to add more, although the extras will probably only be put in place when we are anchored.

The goal is for the panels to be:

  • removable (so we can take them down and put them below in a storm)
  • foldable (so we can let them hang down alongside the guardrails when we are docking etc)
  • tiltable (so we can improve efficiency by improving the angle to the sun). This will also allow them to compensate for the boat heeling so we can keep the ones on the “downside” out of reach of waves.
  • stackable (we want the edges to provide protection so that we can stack them on deck or below without damaging the actual panel sections).

We have been through lots and lots of ideas for attaching the panels looking at all the examples we can find while trying to keep the costs and amount of work to a minimum.

The existing stanchions are too widely spaced to be used to directly attach the panels (and a little too low). The wires between them will not be rigid enough (and neither are designed for these loads in addition to the load if someone is thrown against them). So we looked at adding legs to support them panels but then everything was getting very complex, heavy and time consuming.

Currently we have just one stanchion between the pushpit and side gate. That length is plenty for two solar panels.

So the current plan is to remove the one stanchion and replace it with four. Two per panel.

The panels will have two wood beams across their underside and these will bolt a point along the long edge of the panel to the top of a stanchion. The panel can hang down from the stanchions in it’s stored position and a dyneema guy-line going up to a low fiction ring attached to the nearest shroud will be used to lift the outer edge of the panel to adjust the tilt.

The aftermost of these stanchions will be very close to the pushpit (the panel will overlap the first part of the pushpit). We will use dyneema lifelines and as these stanchions are taller than the rest we will have 3 lines at this point (top one goes up from the pushpit and down to the gate).

To remove a panel we just need to undo the two bolts and disconnect the dyneema.

It looks like it will be cheaper to buy carbon fibre tubes and make our own way of attaching them to the deck than to buy stainless steel stanchions and bases. Plus Carbon Fibre tubes won’t need any bolts through the deck but it will be a bit more time consuming to fabricate. However, it is something we can put off for a while – we don’t need this to launch.

Chainplate and Mast Tang feedback

Today I have had a couple of really helpful and thoughtful comments from Jacob. So much that I think it worth responding with a post.

In Dyneema Termination and Chainplate update Jacob wrote:

Having extras in the case of the DIY tangs, is a good idea. I do not mean to discourage your idea, but the tensile strength of UHMWPE will surely make the tang the weak link. On another note, if stainless steel sailmakers thimbles will work you, USStainless.com has a 12 mm (M12)

So things have moved on a little. Currently we are looking at using recycled HDPE (see Transforming waste with DIY Plastic recycling) so we should be able to make new tangs anywhere in the world from waste plastic. I think HDPE sounds better for this application than UHMWPE eg creep under load. They can be made by melting the plastic in a grill or oven or using a hob (use a pyrex bowl in a bath of oil to get the temperature high enough) and then a simple home made mould (eg a drainage tube with a clamp to provide pressure to a a plug sliding inside the tube).

My idea to make the tang out of plastic is intended to have a number of advantages over my first idea of stainless steel tube and washers( see last but one paragraph of Termination of Dyneema Shrouds. The most contentious issue?):

  • Cost (especially if we make them from recycled HDPE)
  • Reduced chafe of the Dyneema Eye splice due to smoother transition to ears which will stop the eye splice sliding sideways off the tang.
  • Increased strength of the eye splice due to the larger bend radius

I’m now thinking of a further refinement. We could put a 25mm Stainless Tube onto the bolt. Then a 25mm hole in the HDPE tang which fits onto the tube. This way the HDPE can’t be “sawn” through by the bolt thread and there is a much larger bearing surface for the HDPE. If the HDPE does wear through then the dyneema will still be around a smooth 25mm tube.

Then on Simpler Dyneema Chainplates Jacob wrote:

I really like your idea and have thought of doing a similar set-up on my boat, too, a Southern Cross 31. I was thinking of using 10 mm Dyneema with a stopper knot through the bulwark, with an aluminum bronze or G10 backing plate running the length of the bulwark that would have my shrouds holed through. This is for distributing the load a bit better. Then eye splicing the other end around a frictionless ring or sailmakers thimble. I am worried mostly about the load on this part of the boat that previous had a different/lesser load on it. Are you worried about this? That is the bulwark maybe not having the structural integrity to deal with the greatest loads your boat might need to withstand.

This is really helpful. I do think the application is going to need to be customised for every boat as there are such wide variations in the positioning of the chainplates and the structure of the hull/deck joint and bulwark, if there is one.

The chances of a stopper knot slipping worries me, also how much weaker a knot is than an eye splice. Yachting Monthly found the Dyneema strength reduce to 35% of the original by an overhand knot.

So if using a knot I’d put it through an eye splice to stop the slipping, as in this video https://www.youtube.com/watch?v=jU_mmdbQeCQ

However, I think my solution is easier and stronger. A length of dyneema with an eye splice at each end. First eye over the low friction ring. Then out of the bulwark through one hole, back out through another and put the second eye over the low friction ring (I’ve thought I’d go around the low friction ring and out/in the bulwark one extra time). The ability to get a larger low friction ring that can take two eye splices is a key reason for me moving from a Stainless Steel thimble.

As for the bulwark backing plate, this is where construction varies such as lot as does the height of the bulwark and the position of the chainplates. I included a sketch of our thinking in my Dyneema Rigging Summary post.

My understanding is that bonding the plate with thickened epoxy is going to distribute loads much more evenly than bolts ever will (providing the material behind it is well bonded together). Also that having two holes for the lashing to spread the load is better. Also a horizontal spread shares load better than vertical, however, I would have thought that the load will reduce very quickly with distance from the hole, so a lot of the full length backing plate won’t be helping at all.

We have a “decorative” rubbing strip quite close to the hull/deck joint. This means a full length backing plate would be very thin and a bit high. So we will cut sections out of this for more triangular backing plates.

I’m pretty happy that due to the construction our bulwark is strong. However, between internal and external backing plates I think it will often be possible to get the strength you need. If in any doubt about the quality of bonding to the hull a bolt or three should make a very strong connection between inner and outer backing plates (but at a cost for inspection and potential waterproofing and corrosion issues.

If you are concerned about moving away from a chainplate bolted to a bulkhead transferring the load down to the hull then maybe look at internal G10 knees bonded to the hull and bulkhead.

As for the material of the backing plates. My preference after reading a Practical Sailor test of backing plates if for G10 epoxied into place (also easier to process to get a really smooth path for the dyneema).

Hope this helps 🙂

Easier anchor recovery

I recently found this product: The AnchorRescue II which looks like an excellent option for being able to trip your anchor if needed without all the problems of using a traditional trip-line to a buoy (tangles, other people picking it up etc).

It is good that it is a 2nd generation product, there have been others using somewhat similar concepts but this seems to have lasted longer and been improved. I like the fact that once setup you can ignore it until needed. Also that in the latest version it has re-usable velco strips to hold the trip chain to the anchor rather than leaving plastic cable ties at the bottom of the sea.

Wheelhouse plans

I said I was going to write this in my post “In the works“, just taken a bit longer than I thought.

This is what our wheelhouse looks like at the moment. The blue cover is really designed for use when Vida is ashore, or left on a mooring. It doesn’t have any windows and is almost impossible to do up fully from the inside. It is also all one piece which means you have no way of accessing the mainsheet or jib sheets when sailing.

Yes, we know that it definitely cannot be described as pretty!! The slab sections rising up from the cabin clash with every other line on the boat and it is too angular and too high.

However, we have a few more urgent concerns (although if we can make it look better while working on these then all to the good).

Ventilation: Even with the boat ashore in North Wales it got very warm under the wheelhouse on a warm summer day. It would quickly get unbearable to be at the steering wheel in the tropics.

Structure: the windscreen windows have vertical aluminium tubes between them. The stainless steel window frames are screwed to these on their sides and to the GRP at the top and bottom. This has caused corrosion between the different metals. Plus so far as we can tell the aluminium poles are not fixed in place by anything other than the window frames. That seems inadequate if a person gets thrown against it by a wave or a big wave hits it. Fortunately the poles at the aft end are very securely fitted.

Visibility: from our reading we are concerned that there are times when it is important to be able to look out directly rather than through glass (we have never sailed with a windscreen before so haven’t yet experienced the problems of rain and fogging).

Steering wheel: this has been repaired/strengthened before, it still doesn’t feel very strong. We are looking at replacing it with a slightly larger one (we can fit a 600mm wheel without hitting the side or blocking the hatch) should be nicer to use.

Seat: The original plans show a removable seat for the person helming with a backrest. Fitting one s1hould make it much more comfortable to be on watch for several hours.

Our plans.

We are still developing these, so still subject to a lot of change.

First, remove the existing glass a bit at a time and fit new supports that take the weight of the roof on their own. Probably use square section tubes of either stainless steel or carbon fibre. Possibly take them to the coachroof rather than to the existing windscreen base (to provide a bit more slope for better looks). That might allow us to change those big grey slabs at the the front of the wheelhouse so that they are slightly curved to blend in better (attach shaped rigid foam and cover with a fibreglass, then layers of epoxy fairing before paint).

Second, refit the glass (or switch to acrylic to match the rest of the windows and hatches except not tinted) but only go high enough to see through it when seated. So it would look much more like the fixed windscreens of a a Najad (see below). The effect would be a but like a windscreen with solid bimini above it. The key advantage is that when you stand to steer, you look out above the windscreen with your 360 degree view unimpeded by anything. This is a bit like what the Amel’s have (see Delos videos) but the dimensions are more horizontally squashed as Vida is 38 feet and the Amels 50 feet long. One other difference is that we would like to fit the glass/acrylic so that it can be hinged open or easily removed for maximum ventilation (this is one reason for switching to Acrylic rather than cutting toughened glass and sourcing new frames).

The next job will be to create a connection between the windscreen and the “bimini” (existing wheelhouse roof) that can removed/opened for ventilation and closed in cold/wet weather. One option is to simply continue with the lines of the windscreen to the roof, attaching to the support struts. Another option is to cap the windscreen with a shelf that extends into the wheelhouse (we need to do careful measurements to see if this is possible without always banging your head on it when coming in or out of the cabin). We could then have small, nearly vertical opening windows to fill the gap to the wheelhouse roof. The front of the wheelhouse roof would then be an eyebrow giving rain protection to the upper windscreen making it easier to see out in the rain. We have seen a number of boats with a soft fabric “window” in this position (although generally the bimini is further back and these removable sections are quite gently sloping (we just don’t have the cockpit length to do that).

Then we will create “curtains” or side walls for the back and sides (we have toyed with the idea of some of the sides being rigid acrylic). Unlike the existing blue cover we will have multiple sections that can be zipped in and out independently. They will also be mostly transparent (with protective drop down covers on the outside). We will be able to remove them and have mosquito mesh when appropriate. When not tacking much we should be able to sail with the windward side and 1/3 of the back in place if needed for warmth or sun protection. This will allow us to easily zip open (or closed) “door” shapes from both inside and outside making access easier whether at sea, at anchor or ashore.

At the moment we don’t think there is any point in replacing the wheelhouse roof for something a little shorter that might look better with some of the windscreen options. We certainly don’t want to “downgrade” from a solid roof to a fabric bimini that won’t last very long by comparison. If you want to sit fully exposed to the elements then by all means use the aft seat of the cockpit or sit on the cabin roof.

While this is quite a bit of work, the costs should be relatively low. Certainly it is far more sustainable to work with a 44 year old boat rather than buy something new. Improving the looks is the hardest challenge due to the space constraints (and the need for standing headroom). However, if we can improve strength, ventilation, visibility and access with much the same look then that will be a significant improvement for us.

Simpler Dyneema Chainplates

[Update] I have written a lot about Dyneema standing rigging so I now have a guide to it all in: Dyneema / Synthetic Rigging Summary[End Update]

Updated design now completed see Next generation Dyneema Chainplates.

When I was coming up with the design of through deck dyneema chainstays and the update I had referred to this video from Free Range Sailing.

The key bits are are at 1m30s and 16m30s.

Since then I have had another idea, this should work for any boat that has strong bulwarks

I had ruled out exactly copying Free Range Sailing Sailing solution as it relied on being able to drill holes that went through the transom without going inside the boat. Therefore they didn’t need to worry about a waterproof solution. However, I have already adapted their solution for a drogue attachment. Now I am bringing the two ideas together.

I had another smaller concern, they have lashed the Low Friction Ring on with 4mm Dyneema and used knots to secure the lashing. Knots are not a good option for Dyneema, they are weak and can slip.

So I have a new design. Rather then keep the existing chainstay positions I am going to move them all slightly outboard to the bulwark. In this photo you can see a couple of shrouds attached to chainplates (circled in red).

Note that the bulwark here does not have the toerail cap fitted (and it still isn’t fitted). The bulwark is part of the joint between the deck and the hull. It is built really strongly and part of the problem we have at present is that the loads from the shrouds are not transferred into the hull but instead can lift the deck which is what has caused cracks (only in one place). Here is the a snippet from an original drawing showing the chainplates but we don’t have a drawing for the ketch rig and the mizzen chainplates are further inward away from the hull. Note that only the main mast cap shrouds (one per side to the top of the main mast) have the stainless steel strip bolted to a bulkhead for much greater strength.

So my new idea is to:

Preparation:

  • Drill 2 holes through the bulwark for each chainstay. They will slope down as they go from the inside and they will not go through to the inside of the boat. I’m thinking 25mm diameter at the moment.
  • On the outside of the hull for each chainstay I will fit a 10mm G10 (outside so no need to use the more expensive for fire-resistant FR4 version) backing plate. This will be attached to the hull with thickened epoxy.
  • Smaller holes will be drilled in the backing plate in line with the centre of the larger holes through the bulwark (large enough for 3 strands of 5mm Dyneema line).
  • I’ll plug the holes in the G10 and fill the holes in the bulwark with thickened epoxy.
  • Then I’ll drill the smaller holes from the outside through the middle of the thickened epoxy.
  • Next I fit a G10 backing plate to the inside of the bulwark with thickened epoxy (this is so the shrouds will clear the edge of the toe rail cap).
  • The holes are drilled from the outside through the inner sheet of G10.
  • The holes are very carefully smoothed, especially the entry/exit points which will be very rounded off (in the direction the load will pull the line)

The Chainplate

To avoid knots and to make for a quicker installation I will have a length of 5mm Dyneema with a locked eye splice at each end (4mm plenty for the Mizzen). Also one generously sized Low Friction Ring (suitable for a 5mm line to go 3x around the ring).

  • On the inside of the deck one eye splice is looped over the low friction ring (a reasonably tight fit but not very critical).
  • The other loop is passed through a hole to the outside, along the backing plate and back in through the other hole.
  • It goes around the ring and back out through the bulkhead then back through the second hole
  • The other eye splice is now looped over the low friction ring which is now held in place by more 3x the strength of an eye spliced 5mm Dyneema Line. That is approximately the same strength as a 12mm Dyneema line (but as our Dyneema Shrouds are sized for stretch rather than strength this is plenty to spare).
  • This Low Friction Ring is now lashed to the bottom of the appropriate shroud to hold the mast up.

If we feel that we can’t get the G10 and thickened epoxy smooth enough to avoid chafe on the lashing we could either line the holes with HDPE as Free Range Sailing did, or fit chafe sleeves to the Dyneema.

Conclusion.

Compared to the previous design this solution has a number of advantages:

  • No holes in the deck
  • No waterproofing challenge
  • Even easier to inspect and replace
  • Moves the shroud mounting points slightly outboard which
    • reduces loads as a more favourable angle
    • makes walking past on the side deck easier
    • moves them further from the sails reducing the potential for chafe
  • Less work to fabricate
  • Stronger and no need for any knees to connect the side deck chainstays to the hull.
  • With G10 backing plates epoxied to the hull on the inside and outside (so connected to both hull and deck) with the loads spread widely, the chainstays should be massively stronger.

Plus for anyone needing to re-rig the boat without taking the mast down then the new chainstays can be fully prepared and fitted with the original shrouds in situ.

This is one of the plans I said I was working on the other day.

Learning from anchor testing

When we chose our Spade anchor we read up on all the testing and advice we could find. Some of that was videos by Steve on his SV Panope YouTube channel. Since then he has continued to add many more tests. These are by far the most useful tests I’ve found.

He has tested many different anchors with underwater footage of them in different seabed as well as tests of 180degree resets and more recently a 180degree veering test. The Spade has come out really well in everything apart from rock cobbles and very soft/thin mud. An article on Attainable Adventure Cruising (see below) suggests that a slower setting process might improve the soft mud holding.

All this and a variety of articles on Attainable Adventure Cruising (who are great advocates for the Spade anchor) convince me that we made a good choice with our primary anchor (Spade 30kg).

It seems that there is widespread agreement that Fortress anchors are excellent kedge anchors (great holding, light and folding). So we will get the largest Fortress anchor that we feel we can easily lift into the dinghy as our kedge anchor. The weaknesses in resetting and coping with veering are less significant in the typical uses of a kedge where it is laid from a dinghy to provide a pull at a specific angle (eg to pull you off a beach or as part of a multi anchor hurricane setup).

While it is tempting to think you could/should always go bigger with anchors the costs of upsizing to the next size of Spade would have been significant (bigger windlass that would not have been 12volt, weight on the bow, difficulty in manually moving the anchor). These costs and the inconvenience in general use mean that, in a few years time when we have more experience, we would consider getting a 3rd “Storm” anchor that is a couple of sizes bigger. We are confident that our 30kg is sized so that we should be good in most “unexpected” squalls, gusts or weather changes. If we were to need a larger anchor it would be because we were expecting a hurricane. At that point we would expect some warning and would have moved to a “hurricane hole” and fully prepared the boat. That would include switching over to the “Storm” anchor. It would probably also be a Spade as being able to dismantle it for storage would be critical, Although it could also be a Mantus (potentially better in very soft mud).