Month: January 2021

Simpler Dyneema Chainplates

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[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.

In the works

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At the moment we are working on two sets of ideas.

Chainplates. Following up on a merger between our through deck synthetic chainplates and our Drogue attachment we are looking at whether through Bulwark chainplates might work well.

Wheelhouse. We have been having some conversations on Attainable Adventure Cruising which is making us think about changing our wheelhouse a little for extra strength, improved visibility, more comfort in the tropics as well as better protection in bad weather. Plus it might look better 🙂

The relationship between Convenience and Sustainability

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I’ve been thinking about the relationship between these two concepts. Unfortunately, in my view, both concepts have been manipulated by unscrupulous businesses so that they have been undermined. Recently I saw an ad for composting coffee pods that drove that home for me. Coffee Pods have long been marketed as the most convenient way to get real coffee, but sustainable they are not!

The convenience of just dropping a pod into a machine is hard to deny and they have proved popular in homes, offices and conference rooms. However, they demonstrate three really common problems with buying convenience.

  • Price: A lower purchase price for the machine might seem attractive but just as with Inkjet Printers the real cost (and profit for the manufacturers) is in the consumables. I’ve looked at a number of articles and the cost comparison per “espresso” of buying pods is given as between 2.5 and 10 times more than buying roasted beans. Selling something as “Convenient”, almost without exception, means paying more for it.
  • Quality: I have limited experience of pod coffee. A few friends have had them and several places I’ve been for meetings. I’ve tended to prefer the “Mocha” pods as I’ve generally found the plain coffee pods rather bitter to drink black. They seem to attract opinions at both extremes from brilliant to terrible which makes it hard evaluate. Generally it seems to be accepted that the quality is lower than a reasonable automated espresso machine and considerably lower than a crafted espresso. However, it also seems that many people are completely satisfied with the quality.
  • Sustainability: It is very, very hard to say anything positive about using a disposable pod, even if it is compostable. Packaging such a small quantity is always going to be wasteful at every stage of the journey.

Other attempts are being made to improve the sustainability of pods including reusable metal pods. These do impact the taste (a metal filter changes the taste) and they are a lot less convenient (so even worse coffee that isn’t convenient).

This very negative view of convenience works over many different products that have been developed as and sold as “convenient”. However, I want to suggest that it does not need to be true of all moves towards convenience.

My thinking is that for something to be both convenient and sustainable it will need to be developed in a different way. This will affect

  • the leadership: doing more thinking and planning for yourself so the convenience is very customised to your situation
  • the community: solutions developed by and for a community are likely to be more sustainable (not motivated by profit) and more convenient (because they scratch an itch the community finds).
  • the lifespan: something that lasts and can be adapted overtime tends to increase sustainability. By adapting to circumstances it remains convenient.

So sustainable convenience (for me) implies creative work as a community over an extended period of time. An area that I have experience this in over the last couple of decades is Free Software, particularly everything related to Linux. My first encounters and work in free software communities dates back to the late 1980’s (tools for a software development package called Dataflex). Within 6 months of starting our own software business in 1998 we moved all our servers and development computers to Linux. I’ve used Linux exclusively on servers, desktops and laptops ever since. In that time I have contributed (in small ways) to a dozen or so projects and released our own software as free software. Successful free software can be widely used for decades and in that time can make money for multiple individuals and companies while also being great value and game changing for users. As the code never gets lost it can resurface and be repurposed in new ways throughout it’s life.

Applying this in other areas is tougher.

However, there have been many communities supporting each other over the years and more forming around YouTube channels, social media and blogs. We see sharing of ideas, tools and loads of practical help.

Otherwise, I think there is a lot that can be done to subvert the “system”. As one example we think our ideas on Laundry subvert the selling of electric washing machines for boats as essential conveniences while avoiding the issue of microplastics with handwashing. We hope that we can share many other experiences of practices that really make life more convenient without them being sold as “convenient” (Multi-Cookers on boats for stews etc as a safe, quick and energy efficient are one for us). We can find new conveniences (not needing to buy or carry diesel or petrol or gas) that are missed by the profit seeking companies.

To end. We suggest that the quality of life that is possible sustainably is far greater than the quality of life provided by the conveniences needed to allow you to burn up yourself and the planet unsustainably.

Learning from anchor testing

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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).

Brexit implications

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Amidst the dark days of the catastrophic response by the UK government to the Covid pandemic, the disaster that Brexit was always going to be, continues to unfold.

Unsurprisingly, given the dire impact on so many industries, communities and individuals, little attention is being given for the implications for what is a relatively small number live aboard cruisers.

The loss of freedom of movement was always going to be a huge price to pay. Sure enough, 90 days in the EU within each 180 day period will make cruising the Mediterranean very difficult. It will also make transiting to or from the Mediterranean via the French canals almost impossible. There are several British cruisers who have been spending the winter in places like the marina and boatyard at Almerimar in Spain

It seems that the UK government chose to not agree to the right to work in the EU. This is probably going to impact many cruisers who earn money while cruising. At the moment the impact on musicians touring is in the news but there are potentially huge implications for those earning money while cruising by picking up work, doing remote working, selling or from YouTube etc. Part of the problem is going to be the uncertainty, there will be differences between countries but also between different offices and officials. I suspect that this is going to take years to find clarity.

Another area where there is potential for significant disruption is about what is taken into Europe. In the last week Lorry drivers have had sandwiches confiscated (BBC News).

Under EU rules, travellers from outside the bloc are banned from bringing in meat and dairy products.

“Since Brexit, you are no longer allowed to bring certain foods to Europe, like meat, fruit, vegetables, fish, that kind of stuff,” a Dutch border official told the driver in footage broadcast by TV network NPO 1.

This has obvious implications for cruisers, if officials check yachts for fresh food every time they enter the EU.

Beyond these issues, in terms of Sustainable Sailing, Brexit has other impacts such as reduced value of pensions, reduced value of UK currency. There are also issues related to health cover, insurance, mobile phone charges and more.

With other impacts on sustainability such as UK allows emergency use of bee-harming pesticide already happening and more expected given the views of powerful Brexit figures on employment, pay and every other aspect of life.

Over the next decades Brexit is probably going to have the biggest impact on the Sustainability of Live Aboard Cruising for UK citizens, that impact is almost entirely negative. It may well also cause an increase in the number of seeking to leave for a live aboard cruising future. Increasing demand while also reducing possibility is a pretty fair summary.

More safety from moving to fossil fuel free Sailing

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In my post Safe, Sustainable Coffee for sailing? I made the point that using an electric filter coffee machine is safer because you do not have to pour boiling water. Especially you do not have to pour boiling water onto a tower of things resting on each other (eg V60 filter holder balanced on a mug).

What I didn’t emphasise is that this safety aspect is only possible (or at least far easier) with a switch away from fossil fuels. Many yachts are now fitting small inverters to use small mains electric gadgets. However, unless you design a higher capacity system in terms of renewable generation, batteries, wiring, inverters etc and implement it with gimbled surfaces for extra devices you are not going to be able to make the switch to an electric filter coffee machine (unless you run your engine to recharge your batteries a lot).

Unfortunately, there are few good options for making coffee without mains electrical appliances. A moka pot is probably the only option, but you don’t see many people using them with pan clamps to hold them securely on a hob at sea (and very often see them perched quite precariously on pan supports that are designed for much larger pans. Anyway they are not preference for coffee when sailing, I want a longer drink to provide warmth and comfort rather than a quick shot.

The same comes to other cooking options. An electric multi-cooker (on a gimbled tray) seems a lot safer option for cooking a stew or soup at sea (well most one pot meals) than either a pan or a stovetop pressure cooker. The advantages include:

  • they cook at a lower pressure/temperature than a traditional stovetop pressure cooker.
  • there are fewer exposed hot things to touch and handle. An advantage when cooking is done but it also means that unlike a stovetop pressure cooker or pan it can be held down in place not just clamped to avoid sliding. So should be safer in more violent motions.
  • Unlike most pans they have a securely fitted lid and don’t need to be stirred while cooking. Reduces the chance of hot food going flying around the cabin (several examples from the Vendee Globe this year).

While we don’t plan to fill the boat with lots of electric devices for cooking, these two seem to us to have significant safety benefits that have not been widely recognised. The main safety concerns that have been addressed in past regulations mainly relate to gas explosions or burning fuel.

Safe, Sustainable Coffee for sailing?

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Planning for live aboard cruising on a sailing boat presents particular challenges for one of the highlights of the day – especially if you are aiming for a sustainable life. Almost everything about the environment of sailing makes coffee a challenge, particularly: Availability, Space, Power, and Safety. Clearly we need to get this sorted because otherwise I’m not fit to be around anyone else 😉

As for our expectations. I love coffee and drink a lot, Jane much less. Although we have both worked in a Café which did include barista work we are by no means coffee snobs, so we don’t have the highest standards or expertise 🙂

At home we do have a big commercial grinder (thanks to some lovely friends). We buy our coffee in bulk from TankCoffee, so get away with keeping longer than ideal to benefit from bulk buying prices by starting with great quality beans. We mostly use a Melitta Look IV Therm Timer Filter Coffee Machine. I guess that illustrates what we look for, so no hotplate (spoils the coffee) but also no manual control of temperature and no sophisticated brew cycle that includes a bloom phase.

At the moment we use a very simple plastic holder for filter paper on the boat (we take coffee we have ground at home). When camping I’ve typically used an AeroPress with a cheap Porlex hand grinder (oh look there is now an improved version II and much higher prices).

If we were to want to make Espresso coffee we would really need to have rather fresher beans than we get away with at the moment.

This video from the amazing James Hoffmann: Coffee, Climate Change & Extinction: A conversation with Dr Aaron Davis at Kew was interesting and highlights some of the challenges to coffee for the long term, meanwhile all we do, so far, is try to buy the most ethical coffee with the least big corporations involved as we can.

Availability: Getting hold of coffee and keeping it presents challenges when you are crossing oceans or cruising in remote areas.

Space: A 38 foot boat, particularly an older design has very limited storage which of course challenges high coffee standards in two key ways:
a) shortage of dry places that keep a nice even temperature for storing the coffee
b) a very small galley without much counter or cupboard space.
So that rules out a lot of coffee appliances.

Power: By sailing yacht standards we do have lots of mains electric power but the capacity is limited. That again puts constraints on the number of electric appliances.

Safety: In this video from Ryan and Sophie the dangers of making coffee on a boat were dramatically illustrated.

Our Coffee Plan

Everyone needs a coffee plan! Running out of coffee would be a very serious situation, and I don’t think the RNLI are ready to help us in this kind of emergency. So this is where we are at.

Initially we plan to stick to buying roasted beans in bulk and grinding them as needed. We should be able to carry enough for 6 months at a time without too much difficulty (we currently use between 1 and 1.5kg a month). For us that is a reasonable sweet spot between long storage between shops, quality and price. Hopefully we can buy in beans in decent quantities in most cities – one city every 6 months sounds reasonable 😉 I admit I’m interested in exploring roasting our own beans in the future. Green Beans potentially last a lot longer (up to a year). Maybe we can fund our retirement by roasting coffee to order for the cruising community 😉

When sailing I’m concerned that we avoid any of the (many) ways of making coffee that involve pouring boiling water or unsealed containers with boiling water in them, or free standing stacks of items that hot liquids are moving though. So that rules out all manual forms of coffee filtering, the AeroPress, French Presses and lots of others.

So it looks like a simple filter coffee machine, like we already have, where you add cold water and it puts the hot coffee straight into a non spill, unbreakable thermos flask. Our plan is to have a gimbled tray which can be used for any appliance (induction hob, coffee machine, multi-cooker) so it should be safe to make coffee when heeled or in waves.

If we add one of the higher quality, higher capacity hand grinders (needs less space, less power), then we should be good to go. These can grind to suit Espresso as well as filter machines.

We already have a number of basic thermos style travel mugs which are definitely more suited to a moving boat and drinking outside.

When it comes to making fancier coffees for use at anchor we can look at one of the manual Espresso machines such as a Flair (no power needs and they fold away for storage). There are also an increasing number of ways to froth milk without the steam wand from an Espresso machine.

I’m sure we will also carry an AeroPress as a reliable backup if the filter machine breaks, just a lot of caveats about safety if using at sea.

I’m not interested in a any of the Pod machines (Nespresso etc), while re-usable pods are now available I’ve not heard good things about the drinks they make. Anyway as I prefer a longer drink (such as a long black) you would have to add hot water to the drink.

Using a dyneema pendant as a simple solution

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I’m a great fan of simplifying things, even if I’m not always good at it 🙂

So I love this Dyneema Pendant, which you can buy from Mantus (they call it a Snubber Pendant).

Except, that it is so simple that we will make several of our own. We will probably use a home made soft shackle rather than a shackle to attach it to the snubber line (cheaper, tool free and not going to damage the boat).

Three main uses:

  • A tool and metal free attachment of a snubber line to the anchor chain (the snubber line provides some elasticity which stops the boat pulling the anchor out of the seabed when the bow rises on a wave). One that is easy to undo even after it has been used with heavy loads. Using this means that if you need to put out more chain (for example with a dragging anchor or higher than calculated tide) you don’t first have to pull in some chain (making the situation worse) to untie the snubber, just let the snubber drop in the water, use another pendant and snubber line and recover the original later.
  • As demonstrated in the Mantus video to help recover if a sheet gets angled on a sheet winch.
  • Using a similar technique, use it to recover your Jordan Series Drogue. Tie to a bridle line, connect snubber line and lead that to a winch. When you run out of snubber line at the winch then attach another pendant and snubber line to the bridle line as far out as you can reach, then pull that one in. Repeat until you can put the actual Jordan Series Drogue line on the winch.

There are multiple aspects to the simplicity that I love:

  • Untying it after a significant load is so easy. Essential when recovering a Jordan Series Drogue where the loads can be huge. A traditional rolling hitch will probably need to be doubled and even then very hard to untie.
  • Attaching it to the chain with a cow hitch is so easy, much easier than a rolling hitch and no metal chain hook damaging your deck. This is so important as the critical use with an anchor chain will be when it is rough and the bow is plunging up and down.
  • So easy to create and inspect for damage. So providing you have a stock of Dyneema line you can very easily make a replacement at anytime you need it.

As I say I’d probably attach it to the snubber with a soft shackle which avoids needing a tool to attach, and of course no issues with corrosion or electrolysis. My favourite soft shackle technique is this one (much easier to tie than many others and I think stronger than any which do not bury the ends from the knot):

Continuing Solar planning

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Sadly, we can’t do much but plan at the moment. However, that does at least give us the opportunity to improve those plans.

In More on sustainability, I included a bit about Jimmy Cornell needing to abandon his attempt to sail around the world with zero carbon emissions. So another incentive to improve our plans.

This is what we have so far:

Wheelhouse roof

4 x 40 watt panels (total 160 watts) for the top of the wheelhouse roof. To be connected so that the two sides are in parallel reducing the impact of the considerable shading as the main boom is just above the wheelhouse.

Guardrail mounted

4 x 175 watt panels (total 700 watts) to be fitted alongside the guardrails. They will be moveable, tiltable and removable. So we can have up to 4 on either side of the boat (to catch the sun). While sailing we should be able to have 2 per side (positioned about 3/4 of the way aft), with the option to drop them to be vertical (like canvas side dodgers but with a gap for water drainage below them) for docking or if waves are a problem. But there are plenty of people sailing with these pretty permanently mounted (eg Rigging Doctor, Millennial Falcon, Sailing Project Atticus). We can also remove them and store them below in really bad weather (recognising that ours are larger and hence more windage).

We have been exploring lots of potential ways of fitting these. Quite a lot will end up depending on how our budget goes over the next few years, we explored a cheap getting us started option using lightish timber struts. However we now have a better solution Simplifying guardrail solar panels.

Longer Term Plans:

By adding a solar “arch” (see below) we should have a grand total of 1460 watts. That is more than Jimmy Cornell, plus we will be able to rotate and tilt most of them to improve efficiency. Coupled with significantly reduced power consumption (only 2 people, wind vane steering, only one fridge, no electric winches etc) we think we are heading towards the right ballpark figure.

Solar Arch.

We have lost count of the number of design options we have been through. Here was one. It got pretty complicated as we work around all the constraints. Our fairly narrow stern, mizzen boom and need for Hydrovane self steering make the structure very challenging.

Our current thinking is to mount two 300 watt panels almost completely independent of each other (total 600 watts). Through a combination of rotating and tilting we will be able to position them for maximum efficiency while also being able to have them either clear of the mizzen sail (ie sticking out aft beyond the boat length) or safe for docking or storms (ie extending forward over the mizzen boom and aft cabin) at which point we would not be able to use the mizzen sail. They will also be removable, even at sea so that again we can stow them (probably on deck due to their size) if needed.

Our plan is to first shorten the mizzen boom as much as we can for the existing sails. Longer term we might get a new mizzen sail with a shorter foot but fully battened with a fathead sail (google images of Fathead mainsails), that would keep the boom further out of the way,

Then the implementation we have agreed with Hydrovane puts the actual vane a little higher than normal so that it is clear of the mizzen boom and sail (thus allowing us to tack without having to touch the vane mechanism).

The solar support will start with an upright carbon fibre tube in each aft corner of the deck (or possibly just down the transom a little), these will be positioned so that they are just clear of the boom as it swings across. They will have a diagonal strut going forward and another diagonal going across the stern. There is a vast array of carbon fibre tubes available up to 54mm diameter so we have some calculations to do. We will mount a smaller carbon fibre tube through the deck that will go down to the full where it will be epoxied in, this will stand clear enough of the deck for the main upright to drop onto it and be close to fully self supported, the struts will add more rigidity as a precaution.

The top 500mm or so will be above the diagonal struts and the top part will be filled with thickened epoxy. This is then a base onto which the pole for the solar panel drops. These Carbon Fibre Tubes are designed so that each size slides into the next size up. So the poles for the panels will be one size up from the fixed upright tubes. They too will have a thickened epoxy filling in key places but leaving 500mm open to drop onto the upright tubes. Connecting the tubes this way allows the upper section to be rotated or removed. We will have a hole for a pin will allow the rotation to be locked in two places (and will also stop the top tube lifting off).

A smaller tube will be fitted horizontally to the top of the solar panel upright. Using a smaller diameter will allow us to attach it by through drilling the upright for the horizontal to fit though. The joint area will then be filled with thickened epoxy to lock everything in place. The horizontal tube will only project out on one side of the upright (like an inverted L). Using the rotation and locking pin this can be forwards or backwards from the upright. This horizontal will be approximately 3/4 of the length of one of the solar panels.

To attach the solar panel we have two slightly oversized square tubes. These are the long enough to be fitted to the solar panel (going across the width of it). They have holes drilled in the middle, with short lengths of tube (next size up from the horizontal) fixed into them so that they can slide onto the horizontal tube. This attached the solar panel and allows it to tilt.

To support this we add a smaller tube as a diagonal brace between the upright and the unsupported end of the horizontal tube. At which point it will look a like we have a pair of gallows on the boat with solar panels on top 🙂

All the fixed joints will be created by smaller diameter tubes going through the larger, the smaller tubes will have smaller holes inside the joint so that when the joint area is filled with slightly thickened epoxy they get locked into place. We will also use epoxy fillets on the outside of the joints.

We will use dyneema guys to control the tilt of the panels with the option to use them to lock the rotation in other places than the locking pin allows.

To remove the panels we will use a halyard. We will rig it so that the pull is up a topping lift, that means as the upright tube comes free the whole thing won’t swing wildly about into the mast.

This give us multiple positioning options:

  • Preferred sailing option. Turning the panels aft so clear of the mizzen, with the ability to tilt them either for maximum solar efficiency or for minimal windage (compensating for the boats heel) depending on the conditions.
  • Preferred docked option. Turning the panels forward, the mizzen can’t be used but they are fully within the deck outline so not going to snag on other boats or be a hazard to people on the dock.
  • Moderately bad conditions. Assuming that you have taken the mizzen sail down, turn the panels forward and take the tilting control lines forward for maximum stability (better angle and braced to the deck rather than the support post).
  • Storm conditions expected (whether sailing, at anchor or in a marina). Lift the panels up so the uprights come off the fixed supports (using a halyard that has a low friction loop so that it runs up the mizzen topping lift giving a close to vertical lift). Lower to the deck and secure.
  • At anchor. Rotate and tilt so the panels are close to right angles to the sun, adjust to compensate for both the boat and the sun moving.

Safety

There are obvious concerns about having large panels relatively high in the air. However, there have now been multiple Atlantic crossings by boats similar in size to Vida with panels this size on solar arches.

We do recognise that our design is a little different due to the complications (mizzen and hydrovane). We do not think this design is possible with the typical stainless steel tubing designs. However, carbon fibre tubes can be used for a wide variety of purposes including masts and wind turbines, that support significant loads on unstayed uprights.

Unlike other solutions we have a variety of options do deal with different conditions. We are not creating a fit and forget solution but one that fits with our expectation of Active Solar Generation which we believe is a critical factor in achieving zero fossil fuels. The real potential to increase solar generation isn’t clear but a 30% increase is possible when you can angle correctly and far more if panels can be moved to avoid shading.

Wind generators

We can potentially add a similar pole support base on each side of the boat by the mizzen mast. In suitable conditions a wind generator can then be deployed. Again using the active generation principle. Wind generators are only effective in certain conditions, so why would we want the noise and windage all the time? However, they are the best option for reducing the need for a generator when we need electric power for heating while anchored in winter when there isn’t much sun.