stuartXe

New boat construction - JPK 38 FC

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The waiting is over: My new JPK 38 construction has commenced.

 

This is the first time I buy a brand new boat. Over the last months I visited many owners of other JPK38's, studied every detail of the boat and learned a lot from SA's forum thread, such as "Construction of a Pogo 12.50", for which I am vey grateful.

 

I would now like to document the build process, and share my reasoning as I make certain decisions (JPK leaves a lot of room for customisation), so I decided to start this thread in case it may be of interest to others.

 

The decision to buy a new JPK38 Fast Cruiser

In 2013 I visited JPK Composites in Lorient, France for a test sail of the JPK1010. I was very impressed with the boat's sailing performance, the construction, but especially with the history and philosophy Jean Pierre (Kelbert, aka JPK). That is where I also saw the JPK38 (Hull #1) for the first time. Let's say this trip is where I developed my bias towards JPK boats and started following their many successes.

 

Fast forward to 2015. I moved back to Europe with my wife and kids and started looking for a boat which would be:

  • Fast - Easy planing, but also allow me to sail in light wind conditions (Immagine med summers, little wind in the morning and nice thermal in the afternoons);
  • Practical/Essential - For a while I had a 41' ketch with lot's of teak, systems, cables etc. Let's say I had my fair share of going mad trying to figure out where wires go and removing panels.
  • Comfortable - Enough to cruise for 6 months with wife and 2 young kids, (with specific requirements such as a fixed table in the salon, not a fold down).
  • Singlehanded - small enough and set up to sail and manoeuvre alone.
  • Safe and build to last - Watertight bulkheads, steering system, but also practical (and important) small details I will talk about later. Many boats are (in my view) overly exposed to risks due to rudder loss/damage. My sample is small, but of all the people I know who lost a boat or suffered heavy damage, the cause was always a collision with submerged objects.

In summary: I was looking for a fast boat, big enough to sail with family for 6 months but small enough to singlehand for an afternoon sail. With a practical and pragmatic approach, with nothing superfluous, fast access to all systems, but not compromising on comfort requirements. Safe and built to a high standard. A fast cruiser, not a racer ok for cruising.

 

post-106179-0-67580400-1478171949_thumb.jpeg

 

Other boats I considered

I looked at new designs and older designs. I like the modern fast planing hulls such as JPK, Pogo, RM. These are potentially not sailing as high to windward as a J boat or Italia yachts, but making comparable VMG by sailing deeper, more comfortable, angles. These where my top 3 builders. They are all smaller yards and offer a higher degree of customisation compared to other production boats. I visited them all but frankly I found the JPK38 to tick all my boxes so I did not invest as much time researching the other boats. Once you get to your top 3/4 boats, the final decision has an element of "feeling". To me the JPK38 is perfect in it's balance of performance, practicality and comfort and I prefer the interior layout compared to other boats I considered.

 

post-106179-0-45200200-1478174345_thumb.jpg

 

New Vs Used

I always bought (very) old boats and didn't see myself buying a new one. In fact I would probably still advise anyone to buy a used boat unless they have very specific requirements and can work with a flexible builder. But I decided to buy a new JPK38, despite the long waiting list, and this is why:

  • Learning - Jean Pierre is passionate about his job, very experienced, and loves to share his knowledge. This may sound like a general comment but you need to meet him to understand what I mean. Working with him, and with his suppliers, on every detail of the boat has proven to be really valuable.
  • Customization - You can (and many owners do) sign a contract for a JPK and only show up for the delivery and get an amazing boat. But if you want to make changes, I'd go as far as say the sky is the limit. JP will send you to talk to all is suppliers directly in total transparency on pricing and details. I have to admit I did not realise the level of flexibility both within the yard as well as with the suppliers. I wanted many things in a specific way and for every idea or request, Jean Pierre will listen, contribute and help make sure the boat he builds is exactly what you want.
  • Value - JPK's tend to hold their value well. There are multiple reasons for this: There is along waiting list (over 12 months), with demand far exceeding supply. JP's philosophy is to slowly grow organically. He is resisting the temptation of scaling (despite the proposals), because he values having a personal relationship with each customer, and you genuinely feel this. Last week I asked him if he was thinking of an upgrade, in marketing terms a "JPK 38.2" type thing and his reply was very direct: "That is not my style. I discussed with Jacques (the designer) and we can't think of what to do to improve the hull. Each boat is personal and different. I would not make a v.2 for marketing, that is just not my style, it would also damage the resale value of my boats."

post-106179-0-29801300-1478176086_thumb.png

 

Racing consideration

I like to race, but decided not to put racing in the key decision factors for 2 reasons: JPK is well known for it's performance racers (JPK 1010 and 10.80), but once loaded for cruising this performance is reduced . Most importantly, the boat/sailplan is designed to optimise the boat's rating. With the JPK38, Jean Pierre and Jacques Valer (the designer), basically put rating aside and said "let's just make it fast, but comfortable for cruising". The result is that the JPK is a very fast boat compared to similar size racers, with 1st place in many non-adjusted races. You won't win a race on corrected time, but you will have plenty of fun and be among the front runners. Having said all this, I know that one JPK38 will enter the Transquadra in 2017, and the owner has been working on some adjustments to improve the boat's rating. I myself plan on doing some of the med offshore races, but 90% of my use will be cruising and local club races.

 

Ok now you know why I chose the JPK38. Construction started at the end of September, delivery is scheduled for January 2017. As I go trough the process of researching and defining all aspects of the new boat I'll update this thread!

 

Ciao

Stuart

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Congrats StuartXe. January is just around the corner!

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Nice, congrats.

Which hull number do you get ?

Like the remark of not doing v2 just for marketing.

And it will be Med based I assume.

Youre right about water ingress due to rudder loss etc. Hope to see how its solved with cables etc.

Have a good trip during the build.

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My boat will be JPK38 hull #19. The plan is to commission the boat in Lorient in January, and in Mach/April sail to the med (Sardinia) where the boat will be based.

 

I'll post as I cover some of the key aspects including: Construction, Rigging, Electronics, Sails, Chandlery, Carpentry, Systems etc.
This is the boat on the day construction commenced:
post-106179-0-61957400-1478180873_thumb.jpg

 

 

 

 

 

 

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Watertight bulkheads

The approach of JPK on watertight bulkheads is one of the reasons I like this yard. I saw many new boats where a perfectly watertight bulkhead is compromised with with lots of holes to pass wires etc.. so I discussed this concern with JPK. This is how the boat is built and my considerations:

 

Crashbox

The bulkhead separating the chain locker is structural and watertight (no holes); no problem to be addressed. One idea I am considering is fitting a watertight hatch to access the anchor locker from the V berth: This would allow me to move anchor and chain to a more central position on long passages. Not decided on whether to do this now or leave as a retrofit for later, but I may just leave it for when I have a need for it.

 

Aft bulkhead

post-106179-0-72088300-1478185154_thumb.jpg

 

The bulkhead is structural, the entire steering system is behind the bulkhead, meaning that if the aft (rudder) compartment was flooded the water pressure would not collapse it, and the boat will remain afloat.

The problem is that a series of electrical wires, engine throttle cables and hose pipes (exhaust, deck shower) need to pass through the bulkhead.

 

The solution adopted by JPK is to:

  • Minimise the number and dimension of holes;
  • Make all holes in the bulkhead well above waterline (considering boat heel);
  • Seal the the holes with a sealant after the wires are passed (As the holes are above waterline there is low pressure on these, the Sealant has also the function of preventing chafe of the wires on the bulkhead (which is a long term cause of problems on any boat).

I looked at other boats (Imoca, Class 40, Open 50, and some expedition aluminum boats) and raised these comments with them:

  • Possibility of passing a plastic thru deck fitting to reduce chafe of wires;
  • Possibility of using deck seals for cables;

The conclusion is that whilst the sealant option (JPK standard) is more of a hassle if you need to re-run the cables, the simplest one to reduce chafe and ensure 100% watertightness without having to cut hoses and running through a deck fitting (which poses another set of problems). So I decided to go with this approach. If anyone has an experience to share it would be most welcome

 

post-106179-0-24538300-1478186265_thumb.png post-106179-0-66531700-1478186267_thumb.png

 

post-106179-0-63960200-1478186262_thumb.png post-106179-0-83198000-1478186260_thumb.png

 

My next post will deal with rudder and how to reduce damage / water ingress in the event of a collission.

 

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And think of the aft compartment as a flotation box too.

Keep cables high, and be prepared to cut all hoses and wires and plug them (easy with some plywood, prepared foam) high up the pressure is low. Throttle cables and exhaust holes will be the hardest.

 

Oh and for that sealant you can think of using something like spartite. Specially if cables can go from upward position in a bend through the bulkhead and up again, I can think then of making a box there, fill it with spartite, and remove box. Do not know the trick of JPK to get the sealant placed like that.

 

I cut an oval in front bulkhead, oversized plywood oval with a foam cord, fixed with a few bolts and voila, entry of forward area.

This access is mandatory in the Classe Mini.

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Will follow with interest Stuart. Shaggy your a thread trend setter.

Me as well. Quite a few build threads in CA now and over the years. Almost needs its own category. They are the most interesting to me next to OR.

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Is there any reason you can't glass a fiberglass or carbon tube from the transom forward through the bulkhead for the exhaust and attach the hose fwd of the bulkhead.

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Is there any reason you can't glass a fiberglass or carbon tube from the transom forward through the bulkhead for the exhaust and attach the hose fwd of the bulkhead.

 

Thanks for the suggestion, It could be a good idea and I did think of this but a hard tube poses another set of issues if it where to crack (collission, someone stepping on it, or else) and there may be other considerations to make if a hard tube is used to replace an exhaust hose (temperature etc). But a similar idea could be to have one hose from the transom to the bulkhead, where a "thru bulkhead" fitting (i.e. a glassed hard tube as per the picture I posted) would act as junction between the hose in the aft and fore compartment. You could do the same with the deck shower and other things and therefore have an entirely sealed bulkhead. The price of this would however be that all hoses are cut, and joined on the "thru bulkhead fittings" with hose clamps. In the spirit of choosing the simplest option that gives the desired result, I am happy to have the hoses run thru holes high in the bulkhead, without being cut, and sealed. It just means more work as and when they need to be removed/replaced but that should be a long way from now and anyway not a very hard job.

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And think of the aft compartment as a flotation box too.

Keep cables high, and be prepared to cut all hoses and wires and plug them (easy with some plywood, prepared foam) high up the pressure is low. Throttle cables and exhaust holes will be the hardest.

 

Oh and for that sealant you can think of using something like spartite. Specially if cables can go from upward position in a bend through the bulkhead and up again, I can think then of making a box there, fill it with spartite, and remove box. Do not know the trick of JPK to get the sealant placed like that.

 

I cut an oval in front bulkhead, oversized plywood oval with a foam cord, fixed with a few bolts and voila, entry of forward area.

This access is mandatory in the Classe Mini.

 

Thanks LeonV, vey useful tips. I didn't think of the aft compartment as a flotation box but that makes sense. I'll actually discuss this next time I see the designer: I wonder if the aft compartment was sealed from the top (it isn't as there is a bit hatch for access), how much would this help on water ingress in the cabin.

Fore bulkhead access and use of sprartite, good tips. Thanks

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Using fiberglass pipe for exhaust is very common in custom race boat builds.

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Glass in a fiberglass tube bigger then the exhaust hose and slide the hose thur. do the same for the wire. A sealed conduit passing thur a flotation compartment is not a new idea. Same as bowsprit slider tube that passes thur a bow compartment. I have used Vernatube

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Thanks for the good feedback on watertight bulkheads, very useful and informative comments.

 

On a related subject, I would like to cover the topic of rudders. I know many people who reject the idea of twin spade rudders with no protection, but considering the importance for good steering balance on these boats, and after my research, this is what lead me to be happy with the JPK arrangement:

 

post-106179-0-07896400-1478335744_thumb.jpg

 

Standard JPK 38 construction:

Twin rudders with rudder tube glassed on a monolithic GRP section on the hull. Self aligning bearing.

 

post-106179-0-01699000-1478334288_thumb.png post-106179-0-15987400-1478334291_thumb.png post-106179-0-13055700-1478334295_thumb.png

 

the rudder tube is lead high above the waterline. I discussed the merits of taking the rudder tube all the way to the cockpit sole, but this poses the problem of how to attach the autopilot arm below deck. Finally I was satisfied with the JPK approach: the philosophy is that the "fuse", the weakest link, should be the rudder itself. I guess this means not over dimensioning the rudder stock so in the event of collision the rudder should break long before damaging the hull/tearing the rudder tube.

 

I was "reassured" by two past experience stories (I believe JPK 10.80): One hit a submerged object going fast, rudder broke, no water ingress, other rudder was ok to sail back. And another who run aground, was left grinding on the rocks at low tide, rudders broke but no water ingress nor structural damage at all when they got back to get the boat.

 

So in a nutshell, I am satisfied with the standard JPK rudder construction and I subscribe to the "weakest link" philosophy.

 

The only concern that was raised (by a friend) is the "flexible seal" used to connect the rudder tube to the stock (last picture on the right, don't know the name if that), I have basically been told that on class 40 with the high pressure generated by the water they can inflate like a baloon. JPK said they never had a problem. They offered another option which they used on the 10.80, whereby the autopilot arm is fixed directly where the rudder tube ends (with seal), but he advised against it as that system does pass some leaks, whilst the original system has never given trouble. This is an area where I have no expertise but I trust their recommendations.

 

 

 

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Did you order the fin/bulb or swing keel?

 

I went for the fixed keel (2.2m).

 

I admit I did not know much about swing keels before this process and had lots of (unfounded) prejudices. I now believe swing keels have many advantages and no sail performance loss (rating loss yes). The owners of JPK's with swing keel are happy. The only downsides and reasons why I chose fixed keel where:

1. Loss of cabin space for the lifting keel and hydraulics;

2. Extra cost;

3. My desire to minimise systems. A fixed keel works for my needs.

 

In the process I earned that most people not happy with swing keels are those who don't have one, and those who do, love it. Like the monohull/catamaran debate and many things in life!

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If the seals ever balloons, get one that is reinforced is my simple idea.

Oh, and get a piece of that tube, make it airtight and try to balloon it with a compressor.

That will reassure you for the pressure needed.

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Here a few pictures of the boat construction in the past weeks:

 

Hull and Deck are out of the mould:

 

post-106179-0-55491100-1479115554_thumb.jpg post-106179-0-20531100-1479115657_thumb.jpg

 

post-106179-0-20531100-1479115657_thumb.jpg post-106179-0-99278200-1479115696_thumb.jpg

 

Preparation for deck fittings preparation:

 

post-106179-0-73498100-1479115742_thumb.jpg

 

Hull and Deck now next to each other:

 

post-106179-0-17106400-1479115761_thumb.jpg

 

Next up the sail plan and rigging decisions.

 

 

 

 

 

post-106179-0-24985300-1479115665_thumb.jpg

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Admiring the detailed deck mould, even antislip moulding outside toerail.

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I didn't think of it but a jacuzzi for the bowman is a great idea for hot calm days. And if it can be filled with westmarine's new low density bathing water, the weight savings compared to filling the locker with chain is huge. Unfortunately they already cut the hole to access the locker (and also removed the antislip moulding outside toerail):

 

post-106179-0-53018800-1479203633_thumb.jpg

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On the subject of anchoring, and weary of not asking for opinions on the best anchor/rode as this is a topic well covered and one, together with religion, politics and food where most people have different and very strong views and needs. The setup I'm going for is this:

 

Anchor: Spade 15Kg (S80)

Rode: 60m of 8mm G70 Galvanised steel + 16mm Polyester spliced to run through the Quick 1000w windlass

2nd anchor is an Aluminum fortress (FX-16 4.7Kg) with very short chain and Polyester rode.

 

post-106179-0-57247300-1479205939.jpeg

 

My Rationale:

  • 60 meters of 8mm G70 chain weight 84Kg. This is 8Kg LESS than 40m of 10mm G40 chain (92Kg). 40m is the minimum I would consider for cruising so going with G70, for pretty much the same price as G40 I get longer chain, less weight, more strength. For some people value in the G70 is in getting the same chain length for less weight, but weight is also an important factor for anchoring and I would not consider 40m of 8mm G70. For me the value is in getting longer chain for less weight. This means in most cases I can anchor with only chain in the water.
  • When I go to the yard next week I will discuss the merits of adding a (SAFE/Watertight) hatch in the watertight bulkhead separating the anchor locker from the V berth, which I can use to move the chain to a central position on long passages and offshore races.
  • If I do local club races I can disembark the main anchor/chain and keep the Fortress onboard.

For the chain I have asked quotes from 2 suppliers: Maggi Group (Aqua7) and Chainerie Limousines (Force 7).

 

 

 

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Working with JPK and the rigger on mast setup, I'll write a summary soon but have a pressing decision to make regarding halyard shackles:

 

  • Standard is winchards.
  • I'm considering Tylaska's, much more pricey but i'm very comfortable with them.
  • I have been proposed by JP to use textile spool shackles, the cost is low and he says they are very reliable. Does anyone have a view or experience with them as halyard shackles?

 

post-106179-0-65893400-1479313066_thumb.png

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Working with JPK and the rigger on mast setup, I'll write a summary soon but have a pressing decision to make regarding halyard shackles:

 

  • Standard is winchards.
  • I'm considering Tylaska's, much more pricey but i'm very comfortable with them.
  • I have been proposed by JP to use textile spool shackles, the cost is low and he says they are very reliable. Does anyone have a view or experience with them as halyard shackles?

 

attachicon.gifSpool Shackle.png

Used them extensively, very secure if looped on as shown. Seen a few have issues where the loop was done differently. A loop and dog-bone or a soft shackle might be worth consideration. Also different methods might be better in different applications, on the spi where it needs to pivot a Tylaska might be better, a furling jib or main something else and a stay sail might be another too.

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Soft shackles are all well and good if you want to explain to every new crew member how they work for the first dozen times they use them. Wichards may add a little weight but everybody knows what to do with them. This is the same reason I went for spinlock jammers instead of constrictors for my boat, no reeducation required.

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Working with JPK and the rigger on mast setup, I'll write a summary soon but have a pressing decision to make regarding halyard shackles:

 

  • Standard is winchards.
  • I'm considering Tylaska's, much more pricey but i'm very comfortable with them.
  • I have been proposed by JP to use textile spool shackles, the cost is low and he says they are very reliable. Does anyone have a view or experience with them as halyard shackles?

 

attachicon.gifSpool Shackle.png

 

You can make your own soft shackles. Once you know how to make a diamond knot, you can make one in under 2 minutes. Just youtube how.

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This is my mast setup and rationale for the changes I made to the standard setup (Here too working with JP has been very educational):

 

Mast

VMG Soromap Aluminum (anodised black) mast and boom. I considered carbon, but decided to spend the extra budget on other things. There are other things I can do to reduce weight aloft before carbon mast.

 

Halyards at mast

I did a lot of thinking on this subject and finally decided to change the standard setup (all halyards lead to cockpit) and to have 4 halyards at the mast (with a winch on the mast).

  • Genoa and Staysail: On a furler, will stay mostly up. (I'll cover sails on a separate post);
  • Gennaker and A-Spi

I think this is very practical and I learned that many class 40 have this setup (great for sailing single handed when launching/setting the spi), but I will make the Spi halyard long enough that it can be lead to a cockpit clutch if I want to change the setup (sailing with crew).

 

Halyard Rails

2x Rail halyards at the mast. This is an interesting system proposed by JPK, I was not familiar with it as an alternative to clutches: a fixed point on the rail that can be tensioned as required. I attach a picture of the JPK45 setup:

 

post-106179-0-13634700-1479382768_thumb.png

Halyard Shackles

After due consideration, I decided to use Tylaska shackles for the spi halyard (an upgrade on the standard winchard). These will be spliced on the halyards. Having learned about the Tylaska spool shackle, I'll certainly use this elsewhere though as I think it's a great system, but for the Spi I like the pivoting head of the Tylaska, the fact you can handle it with one hand easily in all conditions and the confidence of it not opening. All worth the extra 175 EUR a piece compared to the possible mess of a shackle coming open.

 

Reef lines to cockpit

Standard setup is tack reef at mast, I changed this so the reef cunninghams go to cockpit. Beside the convenience, I considered the psychological aspect of not leaving a possibly nervous crew member alone in the cockpit.

 

Book end

The boom end is flat, I asked about the possibility of adding an attachment point for a preventer or for one of the most important pieces of equipment for any performance cruiser: the single point hammock:

 

post-106179-0-93344500-1479384689_thumb.jpg post-106179-0-36921800-1479384989.png

 

Backstay Adjustment

I changed the standard setup, which requires the use of a winch, to the system used in the JPK10.80, with a purchase system.

 

 

 

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Funny that halyard locking system. How do you fix the position on the track with a simple knob... Its not a pin in track I would think.

Kind of a bierstrekker for big boats.

New are constrictors like from Karver.

 

Oh, so yur reef goes back to cockpit, but halyards on the mast ?

 

Funny it is a bit quiet in this topic, to many are focussed on the Vendee I reckon.

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You tension the halyard with a strop to the winch then drop the pin, then remove the strop. Pretty cool for permantly mounted furled sails.

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Funny that halyard locking system. How do you fix the position on the track with a simple knob... Its not a pin in track I would think.

Kind of a bierstrekker for big boats.

New are constrictors like from Karver.

 

Oh, so yur reef goes back to cockpit, but halyards on the mast ?

 

Funny it is a bit quiet in this topic, to many are focussed on the Vendee I reckon.

 

LeoV, in fact I was surprised nobody commented my mast setup yet so thanks for opening the discussion :) This is my reasoning for having reef lines to cockpit and (some) halyards to mast:

 

It's a setup used on many singlehanded focused boats (Class 40 etc) and, in my view, a setup very convenient for a cruising boat too - I think one reason why it's not seen as much is that it's cheaper to lead lines back than add a winch at the mast:

 

Reef lines to cockpit: as explained in my post, going from Reef 2 to Reef 3 means the conditions are not ideal, leaving an inexperienced crew in cockpit is an unnecessary cause for stress and the convenience of this is good. Obviously at any time this can be changed, it's a 2 line reef system and the mast reef can be done at mast if you want.

 

Spi: Sailing alone it's really useful to be able to rig and launch the spi all from one place and that is why I wanted the spi halyard at the mast. The line is long enough that it can be lead to the cockpit in a crewed situation.

 

The Spi was the main reason why I wanted a winch at the mast. Once I have that, it opened the door for these possibilities:

 

Gennaker: This is also on a furler, so it is rigged all from the bow, working at the mast is much more convenient than going back to hoist it!

Genoa and Staysail Halyards: both on a furler, once up will seldom come down. I see no need of leading these lines to cockpit and the track system (new to me) suggested by JPK seems like a good idea to ensure there is no slip. I'll be able to say more on this when I get to use it :)

 

This is the setup that made most sense to me, the additional cost is about 2K EUR compared to leading all halyards to cockpit. In a crewed situation it is not necessary, but sailing alone, and even for a family (my cases) I think this works best.

 

Constrictors are great, I considered them, but decided to stick with the clutches for familiarity.

 

Ciao

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This is the halyard rail system I described:

 

post-106179-0-00701100-1479633011_thumb.png

 

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Alca, that means its a pin, hole system, so fixed distances... not a big fan of that, but maybe small enough distance between them to make it a moot point.

 

Stu, for spi, mounting a camcleat on the mast too I reckon ?

 

I like mast action with halyards, it makes you come out of the cockpit once in a while, I am a tall guy so can reach high for the mainsail problems etc. A small guy would have all lines led back. Been mastman for years on a 40 ft racer, all due to length and weight.

 

Is there already a trick for the third reefline, I mean like a very small line running from reef eye to reef eye (double so endless) and when putting 2d reef in you tape 1 reef line to endless line and install it. That is the way I did it, but maybe there are smarter solutions found the last years ?

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This is the halyard rail system I described:

 

attachicon.gifScreen Shot 2016-11-20 at 10.08.45 am.png

 

I can envisage a simpler, lower weight version of that system simply using double loops in the ends of the halyards and fixed hooks on the mast. Complexity geting the halyards exactly the right lengths and I'd guess you need a downhaul in that version to adjust luff tension.

 

I'm also assuming this system needs to be winched up to unload it like any other halyard, and I assume a tail is connected to the halyard to lower the sail. How is the tail connected, and does it pass through the sheave at the masthead?

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I have used a system on our frac rig 36er that employs a properly sized halyard with spliced eyes at both ends which exits the mast and sits about 4' above the partners with the jib at full hoist. The bottom eye is sized to allow fitting an Antal ring. A line (strop) dead ends at deck level, runs vertically up to and turns over the ring, back down to a mast base turning block adjacent to the dead end and then back to a winch. Becuase the jib is on a furler and we rarely change jibs, the system works for us. Hoisting the jib is done as mentioned above by another poster with a hoisting halyard with an eye splice on one end and the two are lashed together with some light dyneema. It works for us!

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I have used a system on our frac rig 36er that employs a properly sized halyard with spliced eyes at both ends which exits the mast and sits about 4' above the partners with the jib at full hoist. The bottom eye is sized to allow fitting an Antal ring. A line (strop) dead ends at deck level, runs vertically up to and turns over the ring, back down to a mast base turning block adjacent to the dead end and then back to a winch. Becuase the jib is on a furler and we rarely change jibs, the system works for us. Hoisting the jib is done as mentioned above by another poster with a hoisting halyard with an eye splice on one end and the two are lashed together with some light dyneema. It works for us!

Does the lower purchase part live in a clutch or on the winch?

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So the tracks do away with the need for a clutch, which then eliminates any slippage, chance of someone releasing it, reduces lines to the cockpit etc.

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Might be too paranoid here but I'm a bit uncomfortable with the pin/loop systems that require winch generated tension to free a halyard. Ever drop a handle in a panic? And if single handing is a real possibility perhaps extra caution is a good idea? I'll take a clutch or old fashioned cleat to make sure the sails will come down when I need them to. When was the last time you saw a real knife taped to the mast? Too old school?

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And how does it exactly works with reefing, placing short lines in between track eye and loop on halyard ?

Or a long long track, can not see that work though.

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Oh, that was bad thinking of me.

 

quote Stu;

Genoa and Staysail: On a furler, will stay mostly up.

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So the tracks do away with the need for a clutch, which then eliminates any slippage, chance of someone releasing it, reduces lines to the cockpit etc.

These are the reasons why I decided to go with the track for the furling headsails !! All based on talking to other people and JPK's recommendation. Once installed I can let you know what I think.

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In the meantime the Hull and Deck have been joined last week:

 

post-106179-0-39304900-1479758635_thumb.jpg post-106179-0-66016700-1479758641_thumb.jpg post-106179-0-40531800-1479758648_thumb.jpg

 

and I just arrived in Lorient to spend a week at the yard...

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Today I'm working with the designer on hull graphics. The boat will be flagged in Italy so needs to display a registration number on both sides.

 

Main considerations:

Hull light grey, with a white section near waterline to streamline the hull length;

I also like the idea of curved stripe (red and dark grey), if we find a way to make it not too noisy with name and registration number (I can also just have the name on the stern);

 

My boat and I get to chose my colours, but the design will last 8/10 years and I don't want to get carried away: I want something that works to a buyer if I sell the boat (The owner of "Sailing Yacht A" probably should have posted on SA too before signing off on the construction).

 

I'll be spending the afternoon with the designer and sending mock ups to my wife and kids, here some initial directions,

 

post-106179-0-00713500-1479816428_thumb.png post-106179-0-37545300-1479816434_thumb.png

 


And two more directions:

 

post-106179-0-73502900-1479817120_thumb.png post-106179-0-74398200-1479817125_thumb.png

 

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This is the one that gets most votes for now, Sails are all white, Red Code 0, Black Spi:

 

post-106179-0-54866700-1479841481_thumb.jpg

 

I am also considering whether to put graphics on the sails, I think I'll put just the Circle ("Enso") on the A-Spi with no text:

 

post-106179-0-01111100-1479841477_thumb.jpg

 

 

 

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:)

 

 

In the meantime the Hull and Deck have been joined last week:

attachicon.gifHull-Dek Joint1.JPG attachicon.gifHull-Deck Joint2.JPG attachicon.gifHull-Deck Joint3.JPG



and I just arrived in Lorient to spend a week at the yard...


I'm not a fan of the orange stripes and the white wrap looks a a little loose.

 

 

But if it takes off as a new trend, expect masking tape prices to soar and new aramid and carbon laminate masking tapes to enter the market soon. A boat needs to look good under construction too.

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I just returned to Lorient to visit JPK (after 2 weeks sailing in the Atlantic on a class 40, great experience) and it's great to see all details discussed at the yard on my last visit have been implemented. Today the keel was attached so I'll comment on the main steps of the process:

 

post-106179-0-45492900-1481581688_thumb.jpg

 

After prepping of both surfaces, the keel flange is bedded into it's slot in the hull (actually, the keel is fixed in position and the hull is lowered into position with due attention to alignment and leveling). The keel is "temporarily" put into position with a thick layer of resin: The resin sticks to the hull but not to the keel flange (coated with non stick tape): This makes the keel slot a snug fit for the keel. Once the resin is cured, the keel is removed (hull is lifted off the keel).

 

post-106179-0-00334900-1481581669_thumb.jpg post-106179-0-78464000-1481581674_thumb.jpg

 

Then the whole alignment is repeated, holes are drilled (for the bolts), hull is re-positioned on the keel with a layer of Sika 291. Bolts and backing plates go in.

 

post-106179-0-62945800-1481581671_thumb.jpg post-106179-0-41932000-1481581679_thumb.jpg post-106179-0-15237500-1481581677_thumb.jpg

 

The keel flange is glassed using fiberglass tapes and resin. This is a step that some yards don't do (they just fair with Epoxy), but it makes sense to do it: It does offer some structural benefits, it is not the point: the resin used for this step when fully cured retains some flexibility so it will not crack even if the keel joint flexes. It's a proven method to fair the two parts.

 

post-106179-0-91578600-1481581681_thumb.jpg post-106179-0-03707000-1481581685_thumb.jpg

 

Last step, epoxied and faired.

 

One option I decided to go for is the Keel Laser Beam; It's new but proven to cut through any lines, whales and steel containers (max thickness 150mm) that may cross my keel:

 

post-106179-0-15332900-1481581666_thumb.jpg

 

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I just returned to Lorient to visit JPK (after 2 weeks sailing in the Atlantic on a class 40, great experience) and it's great to see all details discussed at the yard on my last visit have been implemented. Today the keel was attached so I'll comment on the main steps of the process:

 

SNIP

 

Last step, epoxied and faired.

 

One option I decided to go for is the Keel Laser Beam; It's new but proven to cut through any lines, whales and steel containers (max thickness 150mm) that may cross my keel:

 

attachicon.gifLaserKeel.jpg

 

Good stuff.

 

Does the laser beam work on port tackers as well? :lol:

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Rudders and bulb painted fluo orange. I wasn't sure about this but then I heard it's proven to make boats go faster...

 

post-106179-0-93636600-1481836034_thumb.jpg

 

post-106179-0-10611700-1481835353_thumb.jpg

 

post-106179-0-21188100-1481835437_thumb.jpg

 

 

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Rudders and bulb painted fluo orange. I wasn't sure about this but then I heard it's proven to make boats go faster...

 

attachicon.gifOrange2.jpg

 

attachicon.gifOpera Viva1.jpg

 

attachicon.gifIkigai.jpg

 

 

 

The boat looks great! I'm envious...

 

I crossed from the Canaries to Martinique in my last boat which also had twin rudders. The further across we got, the more sargassum we encountered and it would often get hung up on the rudders. I definitely wondered how much better a single, center mounted rudder would have faired. So I quite like the idea of the bright paint which will make it easier to see when the foils are fowled. The loss of speed from only a small amount was dramatic. Why leave the body of the keel in grey?

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Shed shot at evening or early morning is great, its a drive through paint shop.. The new shed looks great.

And the boat too...

 

Only bulb, the fluo is just a bit worse in antifouling efficiency. At least that was the case ten yrs ago.

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When does she launch? Looking forward to more pictures and review.

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Ok, long overdue on updates, the last few months of construction I've been to the yard a lot, spent 2 weeks sailing on a class 40 in the Atlantic, plus 2 months of yoga in India and testing another new toy back in Italy (WASZP), and most important spending time with my family :) now done with the excuses, I post a video of a short sail we did yesterday (the boat was Launched in January, is still in Lorient, I'm now planning the sail to Italy via Gibraltar for May). I'll be resuming my construction comments soon, resuming at the time the Keel was attached and mixing in comments as I sail her and to various jobs on board.

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This is the video of our short sail yesterday in Lorient, the boat is currently really heavy as I'm loading it with cheese, wine and lots of spares for the trip to Italy but still manages a good speed...

 

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Now that's a nice boat! Are there solar panels on there? What do you do for power?

 

Yes, 2 x 50W flexible Solbians, separate charge controller for each like this:

post-106179-0-82988500-1492458187_thumb.jpg

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Then one sunny, calm and (very) cold January morning, Ikigai touched the sea for the first time

 

post-106179-0-78006000-1492458624_thumb.jpg post-106179-0-25662200-1492458663_thumb.jpg

 

post-106179-0-15786900-1492458687_thumb.jpg post-106179-0-70909400-1492458815_thumb.jpg

 

And a busy few days of commissioning, test sails etc...My wife and little son flew home and I stayed on for another week with my eldest son, we moved on the boat, very grateful for the heating we installed, and spent a week sailing around Lorient.

 

 

 

 

 

 

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What a beauty, congratulations!

 

Looking forward to hear the rest of the story, and see some inside pics. How do you like the interior-layout?

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On 3/5/2017 at 8:59 AM, grandsoleil said:

What a beauty, congratulations!

 

Looking forward to hear the rest of the story, and see some inside pics. How do you like the interior-layout?

I'll post pictures of the interior when I get home next week, among similar boats i considered, for me the JpK38 wins for my needs in terms of how the space inside is used. Simple things such as a fixed table that, which can sit 4 comfortably (we had dinner in 8) bit leave the passare forward free. and the 3rd cabin with sea berths and tech room. It looks comfy to live on, yet it never takes more than 30 seconds to reach even the most inaccessible area and systems.

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I'm currently sailing IKIGAI from Lorient to Italy. I crossed Biscay with a few friends, then double handed from Galicia through Gibraltar to med Spain. Currently sailing solo through the Balearics where I'll pick up another friend. Here a short summary after sailing almost 2,000 NM with crew, short handed and solo: I love this boat. Perfectly set up for sailing alone yet big enough for a full crew. We had a couple of storms: at Cabo Ortegal we sailed through the night in steady 40-45kts gusting 60, with cross sea then following. Other than reefing down to reef 3 and Staysail, the NKE autopilot was in full control, never broached etc. It's just a matter of adjusting the Gain as needed and get excited when you surf down a wave!!

In the Alboran sea we hit our current speed record, just over 17.5 kts..still 5 kts under what others have, but we are sailing conservatively and very heavy with all the things im bringing back from France.

The best aspect of all, is how easily you can change gear/mode: Max sail and it feels like winsurfing. Reduce sail and the boat gets comfy for preparing a meal and relaxing with family. Lots of power, but only if you want it!! 

 

FB_IMG_1495542903706.jpg

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Today no wind at all and 70 Miles to go...its days like these that I am happy abt the 40 Hp upgrade, fast under Motor, not only sailing :)FB_IMG_1495614593113.jpg.b4f03ffdf33eb9d632e1c14625739da6.jpg

FB_IMG_1495614548678.jpg.3e1f10e087694fe1c428cbb4140b95ac.jpg 

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This weekend we celebrated 3,000 miles of sailing together since commissioning in January. Solo, with family, with new and old friends. We sailed in 60 kts and in very light winds. She's fast in any conditions, safe and practical. I've not set her up for racing, with a furling staysail etc, but it's been fun to occasionally join a race just for the fun of being in the front all the way, with my kids driving. So much so that the second JPK to come to Italy is being built for a guy that was so impressed he sold his boat (RM, still a very nice boat, but really not as fast) and ordered one :). No buyer's remorse here. Just wish I was sailing more!! Here a pic today in Sardinia. I have not had any major problems to date (nothing that would stop me sailing) but there are a few things on my to do list such as adding a jammer for the spi tack line at the bow so I can rig it all from there when I sail alone and other things. 

JPK38 Ikigai 3000.jpg

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Hi Stuart

Thanks for the thread - very useful stuff. The JPK 38 (along with an older Cigale 14) are on the top of my list. Have heard differing opinions on upwind and light air ability of these type boats. This may refer to the off the wind optimised racing boats (JPK 10.80, most Pogo's, Django's,etc) rather than the fast cruisers of this type of boat (JPK 38, RM's, Pogo 36)

Based on your now 3000 miles of sailing her three questions please :

1. Her light wind performance - light displacement but big hull drag - which wins? Do you sail her well heeled to reduce that drag?

2. How does she sail upwind.Typical angles? Better VMG with sheets eased?

3 .Sailing upwind how does she handle the steep short waves of the Med in say 20 knots (slamming) - compared to say Salona 380, Arcona 380, Solaris 37 type fast cruiser?

I understand that all boats are compromises and that the thrill of sailing these boats offwind could well offset any upwind disadvantages. Or has JPK created the ultimate allrounder? I know that a test sail may answer my questions but none of these boats in Australia yet AFAIK so am relying on these forums to develop my short list before a trip to the boatyards in Europe. We will be keeping the future boat in Europe

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On 10/4/2017 at 12:04 AM, Goofy said:

Hi Stuart

Thanks for the thread - very useful stuff. The JPK 38 (along with an older Cigale 14) are on the top of my list. Have heard differing opinions on upwind and light air ability of these type boats. This may refer to the off the wind optimised racing boats (JPK 10.80, most Pogo's, Django's,etc) rather than the fast cruisers of this type of boat (JPK 38, RM's, Pogo 36)

Based on your now 3000 miles of sailing her three questions please :

1. Her light wind performance - light displacement but big hull drag - which wins? Do you sail her well heeled to reduce that drag?

2. How does she sail upwind.Typical angles? Better VMG with sheets eased?

3 .Sailing upwind how does she handle the steep short waves of the Med in say 20 knots (slamming) - compared to say Salona 380, Arcona 380, Solaris 37 type fast cruiser?

I understand that all boats are compromises and that the thrill of sailing these boats offwind could well offset any upwind disadvantages. Or has JPK created the ultimate allrounder? I know that a test sail may answer my questions but none of these boats in Australia yet AFAIK so am relying on these forums to develop my short list before a trip to the boatyards in Europe. We will be keeping the future boat in Europe

Quick reply as I just saw your post while I wanted to post on something else...

Light wind performance - was one of my criteria - I want to move at decent speed even in the summer low winds we have here when most other sailboats are motoring. In light winds I love the gennaker all the time sailing upwind at 40 degrees angles and even manage to "tack" with it.

Sailing in short waves is regular but somehow no slamming - i did not expect this as I too did not get to test the boat in short sea before - compared to a class 40 or a Pogo 12.50, great boats, the JPK38 project started on a class 40 concept but the hull has a deeper V that makes it way softer yet still easy planing. 

As for sailing angles, I don't have polars but have those a friend of mine made with a VPP program and they are on line with my performance 100% if i'm light and set up to go fast, 90% if cruising. 80% being lazy. I'll send them when I'm on the boat next.

Enjoy the process of boat searching :)

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Possible that a new Wichard U bolt (Pad Eye) has a manufacturing defect (steel is not smooth, so chafing)? Or should I look at the next cause? I've just emailed the sailmaker and rigger for their advice, but thought I'll post here in case someone has a view: 

I noticed that the Wichard U bolt (Pad Eye) on the spinnaker pole (at the Spi/Gennaker tack attachment point) has some damage and is chafing the dyneema lashing of the Spinnaker tack (pics below).
 
I don't know if this was a faulty Wichard U-bolt (I didn't notice it before) but maybe it's the Gennaker Karver furler (attached to the same pad eye with a snap shackle when in use), and when under load it is scratching the steel of the U-bolt ??  Seems unlikely as this is the intended use. Is it possible the Wichard had a manufacturing defect?
 
I don't want to replace the U-bolt and then find the problem persists. I have 2 possible solutions:
 
1. Change the Spi tack line set up - currently passes through a low friction ring and dyneema lashing on the U bolt - to a steel (so the scratched steel won't chafe) - problem solved. 
 
2. But if I want to keep my current set up, assuming the cause of the problem is the furling gennaker's snap shackle, I need to change this. bearing in mind the furler needs to twist so it can't be attached to the spi tack line.
 
   Inline image 1
 
Inline image 2

image.jpeg

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What a good looking boat.

Mazel tov. Sail it well.

Seeing it is like a fresh, just-in-time palate cleanser to retire ones faith and erase the shit-smeared abomination of that whole Wahine debacle. 

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  The shackle for the Karver has deformed the U bolt, creating a nice lip for the lashing to chafe on. Very common problem, not a manufacturing fault, SS is a soft steel because carbon is removed & nickel added to make it stain less. Solution is to attach both systems with rope, after filing/sanding the lips off.

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On 10/27/2017 at 6:08 PM, longy said:

  The shackle for the Karver has deformed the U bolt, creating a nice lip for the lashing to chafe on. Very common problem, not a manufacturing fault, SS is a soft steel because carbon is removed & nickel added to make it stain less. Solution is to attach both systems with rope, after filing/sanding the lips off.

Very quick feedback from Karver this morning. As you point out this issue is not uncommon. Their suggested solution is to replace the standard snap shackle with the 2:1 / 3:1 friction sheave. This, they say, will also better stabilise the drum when furl/unfurling and will make it easier to to install the furler when the bowsprit is out. 

I wonder if setting this up 2:1 I could use the spinnaker's tack line, or what the issue would be if I use the new 3:1 sheave as a spi tack too. 

A simpler, cheaper and workable solution may however just be to splice a soft dyneema loop around the U-bolt on the bowsprit and use the snap shackle on that, which is what I think you too are suggesting. I'm looking for pics of similar set ups. concerned about torsion when furling in heavy wind. I'll start a dedicated thread in gear anarchy or fix it anarchy and revert with the conclusion!image.thumb.png.78359474089edfe1dfc05f366ade01d9.png

 

 

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 Using the 2;1 sheave is the best option. It helps a lot to keep the lower unit from rotating when rolling/unrolling sails. Avoid having any swivels in the system.

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I got some great advice here and elsewhere regarding my Gennaker furler attachment to the bowsprit. I considered all options and here is what I did:

Adding a 2:1 sheave a neat solution and gives an extra control, but given that my halyard is already 2:1 and I'm happy with the tension I get on it I decided to go with the simplest option - keeping the ethos of this boat of minimising systems whenever possible:

The problem was caused because the furler's snap shackle and the U-bolt's round profiles, they worked away on each other till they had enough surface to carry the load. No structural issues but it caused sharp steel parts that chafed by dyneema lashing. I found this to be a very common problem on other boats, but most owners didn't even realise, because the 2 steel parts wear each other out till they get to a good working solution and there are no structural consequences. You only have a problem if on the same U-bolt there are other lashings (as in my case, for the spi tack line). My sister boats (previous 19 JPK38 models) use a shackle and sheave to get the spi tack line on the bowsprit, so they don't have a problem. But I have a low friction ring and dyneema lashing around the U-bolt. I could have just hanged this configuration to the one of the other boat. But I did this instead:

1. Faired the snap shackle and replaced the U-bolt (20 Euro) - so far no rust on the steel I faired.

2. With both parts smoothed, I decided to use a soft connector between the 2, I considered using a soft shackle, a dyneema loop around the prod and other solutions.

3. I temporarily sailed with a webbing loop (I have a few onboard) - This is rated at 22KN so load no problem, but I wasn't sure about UV degradation and possible twist resistance. It worked well temporarily:

 20171112_100551.jpg.dcd0c76a76bd405e20ed3b8891bcf3ef.jpg

3. My final (for now) solution was to splice a dyneema loop + brummel splice: Rather than having just a loop around the U-bolt, I wanted to use the U-bolt to hold its position but also the Prod to load the weight. I made a brummel splice catching the U-bolt in the loop. The brummel splice serves to center the loop on the U-bolt but what carries the load is the loop around the bowsprit. I have then taken the dyneema all the way back into the brummel loop and around again. There is no way this is ever going to come loose :) 

20171112_094556.thumb.jpg.8ea2ae13f4c44b76fbd8306855fcd37e.jpg20171111_173106.thumb.jpg.fda10cfcafb71da9a5feedb8de980d61.jpg

Here you can see it set up with the Spi tack line dyneema lashing:

20171112_100351.thumb.jpg.36f5b57da37a7176a231e67f221fccf7.jpg

 

 

Dyneema loop around the U-bolt - then I saw many boats with this setup but the loop around the  

      

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1 hour ago, stuartXe said:

Dyneema loop around the U-bolt - then I saw many boats with this setup but the loop around the 

NIce, a cliffhanger :)

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In the meantime, lousy installation of a hose fitting of my Eberspacher Heating caused me a cold night at anchor and a bad surprise in the morning:

The main hot air hose came loose, so hot air blew in my aft locker rather than in the cabin. The locker overheated and the heater went into emergency shut off. I restarted it a few times (sometimes it shuts off if there is a back wind) but then I gave up as clearly there was a problem. In the morning I found out the damage. Nothing catastrophic, and I already informed the yard and the insurance (I assume it's a yard's problem rather than insurance):

1. Aft Speakers don't work - they have not been working for a few weeks, problem may be unrelated or perhaps the thin speakers wire coating was the first to melt and short!

2. Autopilot dust cover is distorted - Autopilot works well but I'll have the drive belt checked (Think it's the only part that could suffer heat).

3. A plastic support holding my Navtex antenna has been deformed by the heat - it was made of Forex I believe, which is molded with a heat gun. I'm making a new one in carbon fiber as a first attempt to work carbon rather than glass - opportunity to learn :)

I suspect the temperature may have reached 100/120 degrees for the heater to have gone into Emergency shut off. I know GRP can reach up to 100 degrees during the infusion process in some monolithic sections, so i'm not worried about structural damage to the fiberglass (and there are no signs of any).

There is no visual damage elsewhere but this did make me realise how easy the risk of fire (or heat damage) is and the importance of triple checking any system that could be a fire hazard. All hoses are properly connected, except this one that came loose because it was fastened with a plastic clamp rather than steel!!! Ok the heater has an 80 degrees output temperature so it may not actually be a fire hazard. 

I'll let you know how I get on - hope to have all fixed within a few days.

Here a little video with the damage:  

 

 

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Fantastic thread, and what an interesting process.

Out of curiosity, what did it cost, roughly, to have your boat and rig built? (I have absolutely no idea; I've never done anything like that.). I'm wondering if --one day--I'd want/be able to do something like this.  It sounds like you've put a tremendous amount of thinking into it, so it must be very gratifying to see it come together.

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