Carbon Fiber Chainplates??? | Sailing Wisdom [S6 Ep3]

[@markchodroff250]

Wow ! I seen the making and installing of the carbon and fiberglass chain plates on Duracell Project, I think it would cost 1/4 of those silicone bronze parts and you never have to do anything or worry about them again!

[@markgreen7701]

The Duracel Project on KZbin built multiple carbon chainplates for his boat. Doesn't look too complicated.. www.youtube.com/@TheDuracellProject

[@RiggingDoctor]

I watched their stuff! I love the concept!!

[@knolltop314]

Hopefully ya have opportunity to talk to Matt of DuraCel Project fame.

[@789train]

dont forget you can combine composites . kevlar is really for impact resistance, but you might consider a carbon reinforced composite structure, as carbon fiber tends to be brittle by itself. you can vacumn bag and cook in a homemade oven if you want. am so excited in anticipation of future videos

[@clivestainlesssteelwomble7665]

Think Rock solid and always stable ... Begins with B.. carbon fiber does cause some corrosion. It also de laminates between layers more easily leading to brittle fractures. Your boat your experieces

[@schwizelled]

Young Barnacles is another channel that has a series on a carbon chain plate build. Living On The Ocean is also a channel with a lot uni carbon layups, although I don't think he ever builds a chain plate. But the concepts transfer. I would not attempt it with E-glass, as some suggest. You have to have at least double the thickness (probably more) to match the strength of carbon. And if I were doing this, I would want to ensure that the strength of the chain plate at least matches the breaking strength of the weakest link in the shroud. Probably better if it exceeds by a 50% margin, or so. You want your shroud to break long before the chain plate rips out of the boat. VectorPly is a company that manufactures and distributes composite materials and they have an online program called VectorLam where you can make up a laminate and it'll give you the mechanical properties. It is, of course, an estimate, as much of engineering is. But it's a starting point.

[@braithmiller]

You and your projects are definitely interesting and adventurous. I would like to see how this works. Retro fitting new technology in an old hull.

[@SteinVarjord]

New tech on old hull is no issue in this case. The boat is fibreglass anyway, which fits just fine with carbon, if done right. The point is that bolts are point loads, while a fibre structure spreads the loads much better into the boat structure. The fact that it’s a permanent solution, with zero maintenance, tells the story…

[@johncollins5021]

Sorry I missed your zoom chat. I have worked with carbon fiber for 34 years in the aircraft industry.

[@shantamwoodworks6531]

the boat im buiding right now will have composite chain plates,it will be E-glass and it designed by a naval architech

[@lorenzom7237]

do you have a website?

[@carlospereira9838]

Do not use e-glass for your chain plates you must use uni directional carbon fiber. This is what i was told by the experts. That is what I will be using for my future build on my 49 foot catamaran. Carbon fiber uni on all chain plates and dagger board casings. I will be using basalt on the rest of the hull.

[@789train]

@@carlospereira9838they also make carbon roving of different weights and reinforcing ribbons too

[@MrJhchrist]

@@carlospereira9838 A naval architect or engineer can design almost anything out of anything. E glass is more than fine as long as you have enough, the only benefit of carbon is that it takes less to be as strong, that's it.

[@dan2304]

While Kevlar is difficult to bond with epoxy the tensile strength is also suitable for tensile applications.

[@carlospereira9838]

Hey rigging doctor. A few years ago I spoke with a engineer who specializes in carbon hulls. He worked on a few Volvo race designs. All their boats have carbon fiber chain plates and he told me that the standard design is to build the chain plate 5X the breakage of the shroud. If there are 2 shrouds on the same chain plate then you add them up. He would not tell me the formula he used to calculate how thick or how many layers of carbon fiber is required. On the Duracell project I believe he used 36 layers again that was specific to his build but 5 X the breakage of the shroud is the standard and you must use uni directional carbon fiber.

[@RiggingDoctor]

I found in a book where they recommended doing 20x the wire breaking strength that way the carbon is never stressed. For the dimensions, you simply figure out the breaking strength of the wire x20 to give you the value on the chainplates. Then you take the tensile strength of Carbon Fiber and that gives you the cross sectional surface area for the chainplates. The length of the chainplates comes from the tensile strength of the epoxy which will bond the plate to the hull. This value will be in square inches and between the two factors you can calculate the dimensions of the carbon fiber chainplates. Next step is to talk with the supplier to get a layer count to make that thickness and you are golden!

[@carlospereira9838]

@@RiggingDoctor Wow talk about overbuilt. Considering that the standing rigging tension is only 12 to 15 percent and the diamonds are at 18 to 20 percent breaking strength of the shrouds. I too only use synthetic rigging standard sk78 over heat set ie. dynice dux because its at least 1/3 less. Just replace every 10 years that is what I am planning for my build. As for the chain plates I was told 5X the breaking strength of the shrouds however at 20X the shroud breakage there is no way in hell that these chain plates will ever break. Can you please explain in detail how do you calculate the layers required. My math sucks however I can follow a formula once I under stand it. For example I am planning on using uni carbon fiber 300g to 600g. I like up to 600g because it's easy to work with. Anything more than 600g is very difficult to work with 300g is my favorite. The specs for the carbon fiber is for example 300g sample Tensile Strength 4137 Mpa, Tensile Modulus 242, Density 1.81 g/cm3, Filament Diameter 7.2 um, Yield 207 m/kg Laminate, Thickness 0.3 mm and my breaking strength of sk78 18 mm shroud is 34000 kgs Now with all this info HOW do you calculate how many layers of carbon fiber you need for a 20x breaking strength over the shroud. Please explain formula even the marine architect wont tell me as he only knows wood and aluminum.

[@carlospereira9838]

My last comment I said that the architect only knows wood and aluminum I forgot to mention steel as well. I was reading up more on carbon fiber calculations and it seems that you don't need all the info that I provided in my last comment. Its seems that you only need the Tensile Strength, Modulus, and Thickness. This is the carbon fiber I will be using it's 300g 12k unidirectional the Tensile Strength is 3000 Mpa the Modulus is 210 Gpa and the thickness is 0.167 mm. So with this new info how do you calculate how many layers you will need for 20X shroud breaking strength of 34000 kgs.

[@RiggingDoctor]

The issue with “how many layers” is it depends on the type of cloth. For that you need to ask the manufacturer and they can tell you how thick the cloth layup is. From there you can calculate the number of layers to achieve your thickness. Sadly, I don’t have that answer either but the way to find out is to ask the person you buy the carbon fiber from “how many layers will I need for X thickness?” They will tell you and then you can purchase accordingly.

[@carlospereira9838]

@@RiggingDoctor Thanks for the reply however I am not worried in how much carbon fiber I will order as I will buy enough for all the chain plates and the dagger board casings. The have in stock 300g to 600g all the same spec except for the thickness. Specs are: Tensile Strength 3000 Mpa Modulus Gpa 210 Elongation % 1.5 Weight 300 g/m2 for 300g Thickness 0.167 mm for 300g That is for 300g which is the one I will purchase. What i need to know is how many layers I need and how long the layers need to be from the top of the chain plate down to the hull x2 to cover both sides in order to have 20X 34000 kgs breaking strength of the shroud. The specs above is the only information they provide. I will be building it in an X pattern with the center straps in the middle. Half of the layers in the middle and 1/4 each side for the X pattern. This is what I was told. I don't know what else info I can provide you.

[@johnnyrevel5545]

Expedition Evans is doing carbon fiber and a special ty[e of fiber glass over special foam board now. They are vacuum bagging the parts as well.

[@EngineerK]

Something to think about is the stress strain curve for CF. Steel has a yeild plateau where you can continue stretching it after it riches its yield stress (by about 250%) - hence a ductile material. CF will tend to have a linear curve to failure ie. When yield is reached it fails. From this perspective I think CF chain plate needs to be designed for higher force (1.5 or 2x the yield capacity of your stay?). The chain plate cannot be the weak link in the system and it's lack of a yield plateau has to be considered in the design of the rigging system (you always want the failure point to be in the ductile component of the system ie. the stay).

[@waterworldtrimaran544]

Shayne from Young Barnacles and also Aarie from living on the ocean make nice carbon chainplates, Matt on Duracell cuts his carbon uni's after lamination, reducing strength and leaving square corners which may lead to stress cracking.

[@RiggingDoctor]

I’ve watched both of their videos on their chainplates. They did an amazing job!

[@louisavondart9178]

Use kevlar to bond in the chain plates. It is much more resistant to impact stress than fiberglass. Perfect for interiors, not much advantage on exterior, unless you get shot at.

[@RiggingDoctor]

I will look into that for when we do the chainplates on Windpuff

[@bunkerhill4854]

Why did the original builder of the boat add a strip of “iron” that went all the way to the keel. That seems so unnecessary. There must have been a purpose. Was it part of a grounding system intended to deal with lightning strikes to the rig?

[@AbNomal621]

Given the obvious lug attached to the first plate, I would think there is some grounding scheme.

[@pontoonrob7948]

Buy silicon bronze bar stock, and the thread each end. I have to believe one if your patrons has a bridgeport and would make you some nuts. I did, but unfortunately just sold everything I own to go sailing. Inspired in part by you, however ironic that may be...

[@AlanKaufer]

This may be a moot point if you do end up going with some sort of composite chainplate, but it appears on the video that the bolts you currently have in your chainplates are actually 1/2” bolts with 3/4” inch nuts. If you do end up going back with bronze, you may be able to reduce the bolt size which would have potentially a significant cost reduction

[@michaelsimpson9779]

Bronze to the topside? Did I hear that right? What's with the copper bonding lug? Lightning protection or just a common earth bond? Will the bronze be up to the cyclic loading? If that's the overall intention...?

[@RiggingDoctor]

The copper lug is for the old lighting system when we had steel rigging. I won’t be putting it back on because the synthetic rigging we have won’t conduct electricity to the chainplates to then need to be dissipated to the lightning plate. Bronze, if sized appropriately, will work as well as stainless steel and last a lot longer.

[@michaelsimpson9779]

@@RiggingDoctor it'd be interesting to see some actual tests. The base material of the synthetic rigging will not be conductive, but it will have a moisture content by nature of its environment of use and that moisture will be laden with impurities, I reckon it would have a fair degree of conductivity. Also, thinking slightly further on that, during a storm with electrical activity, it's more than likely that the rigging will be saturated with rainwater..... might have to see how many synthetically rigged boats have been through that scenario. Begs the question. What a can of worms.

[@kennethgrapp8574]

Duracell project did carbon chain in refit

[@daveg4963]

Yes

[@johngalt5887]

Just remember those dudes went down to see Titanic in a carbon fiber submersible….😝

[@michaelsimpson9779]

Carbon. Tension good, compression nooooooooooo

[@IxnayMalarkavitch]

That’s a hard no from me. Carbon fiber is impact sensitive. Whack the top of one of those chain plates on a dock, it’s compromised. Plus you are relying on the interlaminant bond of 40 year old fiberglass. To hold a pretty big spar in place in a hurricane. Others have mentioned lightning so I won’t bother. Bronze is incredibly durable. It tolerates moderate deformation. It’s slightly malleable. Some jerk with a cruddy anchor winds up along side you in a blow, while bronze might bend a little and you’re like, might be able to bend it back with a mallet instead of oh. Now we got to tear all that glasswork out to replace a Chainplate. Lastly you can bolt those on with stainless. Check one every five years. Regarding the bottom bolt in a chainplate. You said you are supposed to leave 20 times the diameter of the fastening below the last bolt?

[@myrlstone8904]

I do know that carbon fiber layups and the tremendous current and voltage surge of a solid lightning strike do not play well together. This was a significant roadblock to the technologies use in aircraft. Though in common use today, it was a steep learning curve getting to this stage. Beechcraft built and sold a number of corporate aircraft ( the Beech Star ship) using a carbon fiber composite structure. Only after being in service was it discovered the vulnerability to electrically caused structural damage, be it from static discharge or lightning strikes. Beechcraft eventually bought these aircraft back seeing the potential for a catastrophic structural failure, and destroyed them. I’ve repaired a number of sail boats having had hard solid lighting strikes. The damage suffered is completely unpredictable even on boats having quality electrical bonding. I’ve seen heavy bonding cables with insulation covering melted from the fraction of a second lightning strike. I would do a deep dive into the subject before adding a direct load bearing component to the standing rigging which could be asked to be a current path in the event of a lightning strike. Particularly so on a boat intended for long distance cruising.

[@PyeGuySailing]

To be honest I'd be terrified to have carbon fiber chain plates...I've watched CF fail on those huge racing boats and its scary. I've watched an entire boat snap in two. Maybe its better, IDK but i hope it works out for you.

[@FTATF]

I think the application is drastically different. In race boats it's about weight and strength, here they can overbuild. I am not an engineer, but the fact that the corrosion factor is nearly eliminated is a very big bonus.

[@PyeGuySailing]

@@FTATF ya, if it works it'd really be a game changer. I'm no engineer either. But bronze chainplates for sure will last longer then he'll have the boat and it's time tested. If I saw some shock load testing done on them I might feel better about them. But he's a smart guy, I'm sure he'll look deeply into everything before hand and if he chooses CF then I trust he knows what he's doing.😁

[@johnbenker1347]

Hot dip galvanize perhaps...

[@RiggingDoctor]

That would give it new life!

[@nodogrunner]

How are chain plates not made out of carbon fiber forevermore?

[@wmstone3914]

Yes you should!

[@RiggingDoctor]

I’m so excited for this project!!

[@wmstone3914]

@@RiggingDoctoryoung barnacles, which I believe you said you watched has a great video. He’s a carbon fiber guru.

[@RiggingDoctor]

Great to know! I love what they built!!

[@robthompson7174]

Shane of Young Barnacles is a composite engineer, that has experience in the marine industry. If I were you, I would approach him, or someone similarly qualified, to consult on this project both for the technical feasibility first, then the expertise to design the system. Having built a 15 meter performance cat with all carbon chainplates (8 of them), all professionally designed and built by qualified composite professionals, I have learned enough about the pitfalls of composite construction to offer the opinion this is NOT an easy peasy DIY project. I got very nervous reading your comment that Total boat have 2" twill woven carbon with " good characteristics". Seriously?

[@billfromgermany]

Mixing composites, eg grp and carbon, is a bad idea - unless you are an Open 60 team with the world’s best design engineers, and the relative budget.

[@pl7868]

Carbon fiber is very good at some things not so good at others , it's no good at all for being shocked as in what happens when you loose a stay an the mast is whipping around , also you have an old boat the glass on it has water in it will be very hard to get a good bond in the first place and would take an engineer to design the fix if it is going to have any chance of being reliable , you may think your boat is overbuilt but there was a reason the designer brought the chain plates down to the floors and keel , I wouldn't try to out think him , just use stainless steel run them down where they belong , won't cost much but will be some work and call it a job well done , stainless is cheap and strong and you can make your own from flat stock , will probably last until your an old man , IMHO

[@DowneastThunderCreations]

👍👍👍

[@davidseslar5798]

Anyone who's caught the "carbon fiber fever" needs to watch and understand the concepts of this excellent short video on the relative characteristics of e-glass, s-glass, kevlar and carbon fiber: kzbin.info/www/bejne/gXm7h5lmiMZ9pqM They may not behave the way you think they do, especially in combination as discussed here: kzbin.info/www/bejne/oGjFgox7qcSkqrc.

[@hatatfatcat]

I didn't know carbon fibre chain plates were a thing, however I do know from my experiences racing bikes that there are 2 types of carbon fibre, the cheap stuff that is basically carbon fibre weave in resin that is made the same as fibre glass, and the 'proper' carbon fibre which is the same thing but is baked when it is laid up and is far stronger. The cheap stuff is rubbish by comparison and will explode into dust and fibre if it experiences a lateral impact whereas the good stuff is more resiliant and better made. Honestly don't skimp on the costs. Secondly why are the bolts and chain plates so expensive??? you could get titanium for that price lol

[@RiggingDoctor]

Fun fact about titanium: grade 7 and 12 are the only two that have any business being used on a boat. Grade 6 is Aviation Grade which is great for airplanes but not a good idea on a boat as it will develop crevice corrosion. The fastener prices are just insane!! I was looking at the carbon fiber from Totalboat and they have a 2x2 twill that has some very nice properties!

[@Lana_Warwick]

I think the "cheap stuff" your referring to "maybe" wetpreg, which this guy, who builds racing boats, incl for Americas Cup, uses & explains why here kzbin.info/www/bejne/n5m4oZeZmJybbM0si=brzHzpFBYwlv9kds&t=5

[@Lana_Warwick]

@@RiggingDoctor Just seen this re dyneema stretch test, thought you might find it interesting. Could obviously do similar pulling it with a car - kzbin.info/www/bejne/boebZHRnbLmil8U

[@deborahdoyle6743]

From what i have seen of carbon fiber i would not use it. Any flex breaks .

[@todddunn945]

Yes, I have seen a carbon fiber mast fail. It happened all at once and was not pretty. That was a professionally built spar not a home built project. The boat was sailing and clipped one shroud a bow sprit on a moored boat. The shroud wasn't visibly damaged but the shock wave literally blew the mast up.

[@dougsrepair1060]

Carbon fibre would certainly take care of the corrosion issues. Why not run the carbon fibre component all the way up through the deck and to the rigging.

[@RiggingDoctor]

That’s how it would go. The fibers run up and over the pin that attaches the rigging. It’s an incredible system!

[@ajnasreddin]

Yeah, well instead of having bolts transfer the forces to the hull, the fiber bond - a mechanical bond - will transfer those forces. Just gluing something in doesn't make it part of the whole. I hope you study it well.

[@RiggingDoctor]

Definitely! This is a topic for much discussion with a composite’s engineer!

[@Frustino]

It's super strong, just don't make a submarine out of it.

[@Tb0n3]

I'm not sure the strength characteristics of carbon fiber is ideal for this kind of application.

[@RiggingDoctor]

What material would you suggest?

[@Tb0n3]

​​@@RiggingDoctora material like steel has much more evident failure modes, whereas carbon fiber will just fall apart immediately on failure instead of stretching. It doesn't like impact which may be an issue when tacking. I haven't watched the whole video yet, so I'm not sure how you're dealing with attachments, but if you drill a hole in it, that's another weakness, but if you cast in a bushing it would probably be a lot stronger. I think shock loads would be significantly more since you like to use dynema which doesn't stretch. Take this all with a grain of salt because I am just a layman not a structural engineer or materials scientist. I was merely answering the question in the title before watching the video based on my own understandings.

[@RiggingDoctor]

There would be a cast bushing at the top. The plan is to overbuild it so that an “impact” shock load would still not be that much of an impact for it

[@JohnJohn-cu7nk]

​@Tb0n3 all racing boats use carbon fibre chain plates at much higher impact loads than a cruising boat

[@oldsailor9022]

Not sure that you need carbon. Weight doesnt seem a critical factor for this project. Why not use unidirectional glass instead. The finished product will be bulkier and heavier, but this shouldn't be a problem.

[@RiggingDoctor]

True! In a 18T boat, shaving a few grams is a fools errand. Do you know of any places that sell unidirectional glass?

[@oldsailor9022]

Uni directional tape is readily available in the UK (East Coast Fibreglass). Google Kurt Hughes on composite chainplates for an informed view as to why you can use glass rather than carbon.

[@anthonyrstrawbridge]

​@@RiggingDoctorAircraft Spruce. I'm not so sure about changing because the fatigue cycles and condition inspection. If I did it, I would do they layup with solid bushings inside and thus still use through bolts. Just my .02 cents.

[@braithmiller]

​@@RiggingDoctor no I have not engineered any chain plates in this manner. Tri-axial S-glass 24oz possibly between unidirectional tape layers.

[@sailingeximius]

Check out the Duracell project for how he builds carbon fiber chainplates

[@deborahdoyle6743]

Check out Alex Thomson's race boat structural failure in the bow of his boat as well as gunrunners carbon fiber mast failure. I respect your desire for the cool factor but your families safety does not need to be cool.