Nick, you continually impress with your astute probing. This tech series is not only informative, it is important to all catamaran owners or potential owners. I have watched each episode with Antoine a few times over and picked up something new each time. Excellent presentation, and sorry he has to go back to work. I have about a dozen more questions I can think of for him. Thanks for the education.
Antione & Seawind thank you for making this level of expertise possible on Nick's TH-cam channel. Each show brings more questions. Your channel here has really helped the individual buyer. Bless You 😃 Merry Christmas 🎄⛄
As a engineer with experience in these material systems, I thank you for technical explanations. I think one particular Catamaran design to understand is the deck to hull material process. Maybe in a future video you could discuss the various ways the deck is attached to the hulls.
A very good intro to a complicated topic! I know this could have gone on for hours, but I would have added some more discussion about both the varieties of sandwich materials other than foam (and not all foams are created equal) and their pros and cons above and below the waterline, as well as how much the lay-up of the GRP/E-glass/S-glass/CF in combination with the sandwich materiel affects the strength, compression, etc. (this was lightly glossed over). Builders are evolving from hand-layup to wet-vacuum to infusion as they get better financing, tooling and experience with the process, but even with the best materials and processes, lack of attention to the properties needed in specific components leads to disaster. I have been riding in pelotons where super expensive carbon bikes exploded under their riders because either the bottom bracket or the top tube were not sufficiently reinforced. I have seen foam cored skis go 90 degrees. And the latest edition of the Vendee Globe shows just how difficult construction can be even with relatively unlimited budgets and the best engineers. I am sure no expense was saved on the construction of PBR and Hugo Boss, yet obviously they were pushed beyond the limits of their materials and construction techniques. One other aspect of this discussion is the economics. Obviously, we all want the best materials and construction, but these come at a cost. What combinations are "good enough" for an ocean crossing cruiser?
Thank you for this video. I am looking at lower costs catamarans and after looking build specs they all use polyester throughout and plywood in the bulkheads. My biggest concern is osmosis.
Re the discussion on hull to deck bonding, etc: I think the discussion got confused. There are really only 2 methods not three, gluing and bonding are the same thing using the same materials (epoxy or poly or vinyl ester), vs taping which applies an additional layer(s) of fiber across the joint in addition to the epoxy or whatnot.
S glass is as strong as carbon (or even stronger in some tests) but its heavier. Talking about balsa, its not just the money end grain balsa has the best bonding strength and is most resistant to debonding/delamination and has better crush resistance than foam. It's also light. The trouble is rot when it gets wet.
While this series has been technical, you have managed to explain it all in a really straightforward, easy to understand way. Sharing knowledge is the cruisers mantra. That makes a huge difference to people with little experience, to gain knowledge and up skill. Well done.The concept is brilliant. i can't wait to see the build underway...
That was great Nick! (great editing as well). Really interesting break down on composite polymer construction. Sounds like there are compromises all over, but having a good knowledge of the basic processes is critical during the buying process. I think it speaks well of Seawind to freely go over all that they do. Very excited for you! Thanks again :) Franny
We decided to strike a balance between too much information and too basic. While the weave and orientation of fibreglass is something that interests me hugely, we felt it may be too much information for a lot of people.
I understand not wanting to complicate the discussion, it's just that the vast majority of cats are made of fiberglass and the quality of glass used is significant especially in the used market. I think an overview of this topic would be helpful for people looking to buy used.
Very useful info on materials from an experienced boatbuilder. May I just add as a structural engineer than just using high grade expensive materials Vs lower performing materials does not necessarily give you a stronger boat. Materials with better physical properties give you higher strength and stiffness per unit weight. They enable a competent designer to produce a high performance boat. However, if you look at Vendée globe now you have a bleeding edge high tech boat made using top quality materials like Hugo boss breaking up and losing bits of the boat until, ultimately, retiring after 4 weeks of racing. And on the other end of the scale you still have numerous well-constructed fiberglass boats from the 1960s and 1970s still happily floating about. They are not nearly as fast but seemingly much stronger.
No they are just less stressed than a IMOCA 60 up on foils hitting waves at 20 to 30+ knots. Ooh and seeing as a IMOCA 60 weights around 8 tons INCLUDING its 3 ton keel their very lightly built !! Alex punched straight through that storm foiling which is probably what started the bow stress cracking his retirement was due to damaging a foil and ripping a rudder off.
That didn't tell us anything about the difference between epoxy and vinyl ester. Some people have suggested there are health effects. I suppose this is due to residual evaporation from the resin. Jeff Schionning talks about the benefits of balsa being far greater compressive and shear strength, he suggests he can use almost half the thickness due to greater shear strength and less fibre either side of the core due to the increased compression strength. So despite being about twice the density of suitable foam the weight increase is not much but the result is stiffer. This didn't mention a property of foam is that it can follow a curved form easier unlike planks. Then prepreg carbon fibre. Given that it has to be stored and laid up in a refrigerated environment then vacuum bagged, I cannot see how it is practical to use it for even a small boat hull. Laying up a hull takes days/weeks so how would a whole shed be kept refrigerated and how would people work in it? Smaller parts and specific areas perhaps. Didn't explain gluing, bonding and taping the deck to the hull. Gluing and bonding sound the same. Taping, wet layup of fibre across the join? Presumably even if the two halves are bonded there is still taping to cover the join if only for aesthetics.
Super informative intro to the basic ingredients. You really have a knack for working the info out and putting it into a practical and useful perspective.
FYI. Even some of us who have never been on a boat like these, won’t be buying a boat or won’t even see a boat such as these find your video very interesting. I watch several channels of travelers such as yourselves and now will pay more attention to their vessels. You and Impi bring your life’s choice to a reality level others don’t achieve. Thank you.
Nice vid Nick, although I think it's a bit quick to exempt balsa core as only chosen because of price. Working with balsa core requires the manufacturer to use a higher standard, ie: sealing the balsa where the core is perforated like thru hulls, deck fittings etc., typically, a high quality builder will remove the core in these areas. As for the wetting out due to water ingress, with the more commonly used "Infusion" methods these days, all gaps are closed off in the sandwich so that the transport of water through a damaged panel is restricted due to the fact that "End Grain Balsa" is used. In general, the resin to core bond is strongest in a balsa core panel and is generally stronger in compression and has superior sheer/ fatigue qualities. Basically, the bad rep comes from bad building practises, causing expensive repairs, like on screwed teak decks that start leaking for example. As a point of interest, in the DIY build kits from Schoinning Catamarans, the prefab Balsa cored panels are actually the strongest/lightest and most expensive option. Really looking forward to your build series and enjoy the build process. Cheers
Something I know for a fact is a big ticket item for many buyers is after market structural and system customisation options for a catamaran. Some manufacturers offer this and some don't. Another good video anyway, tech discussions are interesting.
Wow! amazing video. why has no one else done such a video and it's been left to Nick and Terysa. can you do one on build contracts and should you use solicitors etc? absolutely a fantastic video. Good on ya.
A great idea using Antoine to organise and rank so many nautical and scientific terms. An excellent introduction into the complexity of yacht design and construction. I now know I am not an expert, but I have a better idea what questions to ask.Thank you Nick for a great 5 part series.
Great series. Thank you. And the next question: What are all the bad things that can happens to cats? (There are really two major categories here: accidents that can happen to any boat, and then issues specific to cats.) What kind of accidents, hull breaches, damage, etc? When I was building my first sea kayak I read the book 'Deep Trouble'; accident reports - all the many ways I could die in my kayak. Probably why I'm still alive after 15 years of soloing. I wonder if it's possible, without stepping on toes, or risking being sued, to do a video on specific types of build failures, keel loses, entire frames separating from hulls, layers improperly bonded, most of these are generally monohull construction issues. There's one major brand I won't go near, including their line of cats. I don't know if I'm justified in this prejudice - but I have it. What can and has gone wrong in boat construction that maybe doesn't show up until later? So there are two categories here: what still can happen even though everything was done right? and What are the things done wrong that have made it out of the boat yard?
A couple questions I don’t believe where covered. How do these material hold up over time? Are some better than others? As materials improved over the last 30 years what has been the results? In terms of weight, strength, repairs?
We have a 1975 Iroquois Mk ll 30 ‘ cat. Polyester resin and fiberglass hull , polyester and fiberglass with balsa sandwich deck and cabin. The hull has been in the water for 45 years with no problem. There has been problems where water has penetrated the balsa. Had to replace the cockpit floor with foam and coosa board epoxied . Fortunately the sandwich on the deck and cabin were strong enough by themselves so that no soft spots occurred, the top layer of the sandwich was overbuilt fortunately with the exception of the cockpit floor where water penetrated and destroyed the balsa.
What about core material for bulkheads, deck and the other components? I have owned boats that heavily relied on plywood. It didn't cause any issues while I owned it, but once water starts to infiltrate the wood, rot soon follows with big repair bills to fix the problems. The other thing is chopped mat vs cloth. A lot of quality difference there too.
Also substandard ply wood structural bulkheads in the Lagoons, bending and breaking without any water intrusion, causing them to sag and almost fall apart.
I follow a couple who assemble a big sail cat from premade hull materials, and they parred the two hulls with a' lenght 30- 35 centimeter wide ( looked like 18-22 cm ) hand laminated bands , about 30 layers , With poly . I asked them if they thought that would hold up in a storm , they said that floor and furniture would help , i still doubt it .
Thanks for sharing... One thing I thought of that rarely is discussed is isolation materials. How this could be done with increased thikness of the foam core insted of doing an extra layer like a 2nd sandwich construction? Aren't there any benifits with a thicker and warmer foam core to start with? Any ideas regarding that?
balsa core is used to save weight as much as it is used to save money ... boats with a race pedigree have often chosen to use balsa in places where wisdom would suggest not to ( below the water line ) or in places on the deck which will be punctured by deck fittings - one way companies have got around some of the shortfalls of balsa is to have a grid pattern scored into the layup which allows epoxy to isolate balsa into squares ... and therefore limit water movement though coring should the core be exposed to moisture ....
I assumed the scoring was to allow the material to conform to the contours of the boat. Having watched a few videos of replacing rotten balsa, it looks like many builders are unaware of this, or just don't use enough resin to create an isolation grid.
Excellent video. The obvious statement comes to mind “You get what you pay for.” Or, at least you better - if you are paying the price. Now, cats were singled out here. I would assume the technologies apply to monohull too. Or is there a difference? Also, do most boat builders offer choices within the same models? Or is one model made consistently with the same construction? Unless you get a custom boat, you have to weigh everything from weight, size, room, features above and below deck, handling of the boat, construction materials and construction methods. If you have a very limited budget, it must be so hard choosing and prioritizing features. How do you do it? It could be the difference between going for a new boat or used one, or even a very used one.
In monohulls it is easier as weight isn’t normally an issue. Personally if I were looking for a monohull I’d look for a pre 2008 boat. Well made and a well looked after model will take you around the world
@@sailingrubyrose Absolutely agree - prior to the explosion in charter fleets and boats that are mass produced and don’t last longer than 10yrs. Even a pre- 2006 Bavaria is solid boat. Today’s mass production standards are just creating tons of future landfill..
Excellent info Nick... 2 other aspects are the stringers ( very important) and the gelcoat ... Carbon fibre is light and strong but brittle, can be Cracked and splintered if impacted...aluminium Would be best but very expensive..Only Garcia make an aluminum, go anywhere cat...there are also custom builds..
Bassalt has high abrasion resistance also...it weighs more, but it costs less than Kevlar. on lighter cats, ( one's that typically are intentionally beached ), i would think basalt would be a standard in some areas of the hulls....it's low down weight anyway.
Well done!!! I am a material scientist and i applaud the both of you for this 'general discussion' and .....I certainly like my fiber; nicely Dry and Cake; properly Baked :)
Possibly a tad oversimplification, my sympathies to the Naval Architect to be brought down to this level. However it al least pointed out some basics which I appreciate as I think your intension.
A couple of comments. Don’t assume that a foam core won’t absorb water, there are plenty of older foam cored race boats down here in Oz that have a lot of water in the foam. It doesn’t affect the structural strength, but it can be a weight and osmosis problem. Secondly, epoxy is heat sensitive, which matters if you are in constant sun in the tropics, it can deteriorate and even soften if it gets hot enough. It is even worse if the hull is coloured.
Sounds like Schionning designed cats that are pre peg epoxy are the way to go (foam rather than balsa) compared to standard production cats. Otherwise, how about aluminum in a cat 48 feet or greater? I only know of Garcia aluminum cats that are around 48 feet, otherwise a custom one off like a Mumby 48 or does anyone know of others?
Appreciate the informative videos. For what it’s worth, I think the guest expert would have been able to convey greater detail if he spoke in his native language, with the translation via captions. It seemed like his responses were short simply because he was struggling to find the English words.
So if I'm reading this right, for the mast, you would want to potentially go with pre-preg carbon-fiber, using, at minimum, vinylester. That would give you the most strength while keeping it light (as light as a 70' mast can be!). Is that correct? Also, you would want foam with a higher density sandwiched in the load bearing sections, with less dense foam in the less critical, non essential forms, like molded furniture? Again, going with vinylester as a minimum, with a fiberglass construction. Carbon-fiber would be to cost inhibiting for the entire hull. Or are there certain areas of the huĺl where you would want it? Great job on this series sir!
Hey Nick, I could just imagine myself walking into a boat factory armed with all this information via a bullet point spreadsheet that I’ve amassed after watching all your videos concerning boat building! Do you think that they’ll shoot at me all the while I run out their door once I prod them on how they’ll build my boat!?
I have delivered hundreds of yachts , cats and mono hulls from the factory. You find the creeks very quickly I would say cats mostly , I think it's part of the job.
Nick, very intersting video series. It gives us valuable intel that we didn’t have a clue about before. Thank you for your shrudenes and altruistic sharing. Means a lot 🤝👍
Nick, great great stuff in this series, but now after all this info I want you to tell which manufacturers meet some or most or even all these qualities as I am in the pre stages of purchasing . Throw me a bone, when looking used which is the way to go? ( yes I have viewed your series on all the cats you reviewed ) Thanks a million the work you guys do , the entertainment and the knowledge are top notch!
Honestly mate I can’t tell you about even half of the manufacturers. I know that Outremer use foam core and even some solid fibreglass in impact areas around the keels. They also use a lot of carbon fibre. Seawind of course as mentioned in the video and balance. The rest is for you to enjoy finding out. Don’t forget the free download to help you. Good luck
Very interesting discussion of materials. What can you say about design? You can use the finest materials, but they do no good if there are flaws in the design. (see Parley Revival, e.g.) On the other hand, even the cheapest materials can be used to build a safe boat if it is properly designed and constructed. So, in the end, what is a buyer to do?
Some of the very best racing boats are hand laminated. It takes way more effort to do so however. For example if you want the very best, lightest, strongest layup the builder MUST start and ensure each and every layer is completely free of air bubbles. Excessive resin must be either removed or alternatively have the next layer of glass absorb ALL the remaining resin so that each and every layer has sufficient resin to completely wet out the glass but no more. To that to achieve the highest quality layer layups must finish only when EVERY layer is compiled fully. Lastly peel ply should be used at the very end to enable greatest bonding properties to ,for example tape furniture decks and hull together at final assembly time. But it must be noted that vacuum bagging at that stage has a great effect of ensuring all layers are layer up void free but also with low resin to re-enforcement layer ratios.
Good presentation. Cost is a huge consideration, for most of us anyway. I'd love to see a naval architect video on what is the best combination of compromises to build high quality, yet cost competitive, boats that middle class people can afford to buy. The marriage of quality, performance and affordability is attainable through innovation, but only if the demand is there. Hope your videos change the demand side, which could drive the supply side. Thank you!
This is a great point. Nothing in real life uses 100% of the best most expensive materials. You need to weight the trade offs and costs to build a good product. For example you could build a home that lasts a 1000 years using stainless steel exteriors, steel framing, 12 thick walls for insultation... but why do you need a house to last that long and cost that much?
Back in the day I worked on a prototype bobsled with a composite structure. Kevlar/carbon fiber mesh (6 layers on each side I believe) with a honeycomb core. Still had a fiberglass body shell, but the composite structure took the place of the tradition welded steel frame. We joked it was the only bulletproof bobsled ever built. I even rode the sled on a test run at Calgary during the Olympics there. It was an interesting design exercise.
Great info about catamaran building materials, thanks. It just occurred to me while you were talking about carbon fiber boat/mast whether it would be less safe when lighting strikes or could it be more susceptible to permanent structural damage after a strike, specially at the interface of two joined carbon fiber pieces. I am assuming that's where you have a resistance to the passage of current and possibly maximum heat generated...etc
Just a small comment.. pre-preg does not indicate a higher level of quality... its a time saver in the lay-up/assembly process... thats all. dry sheets of fiber are layed out, liquid resin is spread over and pressed down into the dry fiber. the now "wet" fiber is covered in mylar tape (to maintain separation of wet sheets) and then the sheet is placed in a freezer for later use. placing any resin in a freezer slows down the resin curing process and slightly extends your assembly time. it is no different quality-wise than hand lay-up.
The overall price diference between epoxy and venylesther would be interessting. I allways wonder way one does not want to go all the way in an investment that big.
It’s all about cost saving and because no one asks. The brokers won’t tell you their boats aren’t as well built as the one next door unless you know what to ask
Anton, I'll take a semi-pro stab at this. Epoxy vs vinyl ester is about twice the price. For a big boat, you going to need about 1000 gallons. If you look at retail for example FibreGlast quotes $2,500 per 55 gallons for vinyl ester so $50,000. For Epoxy that would be double. And manufactures can get it a lot cheaper. So let us say is half of that. So only a $25,000 difference. Does not sound like much for a boat that costs $500,000?? The real problem is epoxy is not UV resistant in its basic form. And will not chemically bound with gel-coat. So instead of applying gel-coat, followed by wet on wet laminating resin and finally finishing resin in the mold in one nonstop process. When using epoxy the process gets much more complicated, labor-intensive and time-consuming. With epoxy, you have to stop, wait for curing and then mechanically bond it to the top-coat(sanding). Or even worse hand finish after it is out of the mold. To the point that some boat builders claim the cost on the final hull is 2-5 times more for epoxy. So if you use the rule-of-thumb that the fiberglass shell is 50% of the cost of the boat and the systems the other 50%. Then the $500,000 boat now costs between $750,000 and $1,500,000 when made with epoxy. I hope this is helpful in some small way.
Aluminum? Steel? Mollen? Cupronickel? Even major manufacturers have metal models in their line up, but there is not so much info about it even on youtube. Maybe you can bright that a little on your channel?
So they wax the mold...spray on the gelcoat, then lay up the fiberglass layer below the gelcoat...when and how do they adapt the foam core ( or balsa) to the first layer of fiberglass ? Do they do that prior to the infusion or vacuum bag? I’m curious how they adapt stiff layers of foam core to a compound curved hull mold...great technical series.
Have a look at the TH-cam Series - Life on the Hulls - which shows where he has used different density foams adhered to the Gel Coated Fibreglass mold and where he is also building all his furniture from molds. These plus all the bulkheads etc etc are all taped into place with Fibreglass and glassed over where appropriate. He also illustrates the techniques required for molding the density foams over curved surfaces etc. hope useful. Kind regards Gavin
Hi Nick, good useful info for viewers, it's a slight shame about the choice of shot for click bait, it looks to me that it's a Mk1 Iroquois, built no later than 1970 if my memory serves me plus I'm guessing it's after a hurricane. Maybe a shot of true delimitation would have better.
Apologies for the slightly clickbaity thumbnail. As it’s a slightly dry subject we decided to “pep up” the thumbnail. The video has been live for two weeks and since we changed the thumbnail, More people are clicking on it. I guess it is a means to an end. Btw, the previous thumbnail has the lovely Terysa on. However it seems as if a sunken boat has greater pulling power 🤣🤣🤣
Interesting, but I wonder how many salesman are actually going to know the answers to these questions, To be honest Nick yourself and Terysa did a complete Series on Cat reviews and you never gave us any of these specs? Kinda voided your own rating system, although i 100% don’t think intentionally, the only company i know that advertisers complete wet infusion molding inc Structural Furniture and bulkheads in Amel. Do you see my point? Like a new car dealer if he or she is selling a volvo it’s the best car, then they move to Toyota and suddenly that’s the best car.. what would they know, they didn’t build either, they get a list of selling points provided by the companies, and if luck an independent safety rating! Not preformed under real life conditions, because all heavy 4x4s are normally rated very bad, where a tiny electric Nissan is rated excellent! If the two collided I would want to be in the 4x4 please! I think there is a direct comparison, because as i say, the salesman is not going to have a clue what weave glass was used, what epoxy or probably not even the core, but hey “look at this dishwasher and washer dryer they are standard you know” I think this series needed to be made, I believe it’s interesting ive enjoyed it. I just don’t know how helpful it will be? Probably far far less than it should.. Thanks guys!
It could force the companies into making sure that the salesmen have access to this information. & the salesmen into being sure that they know it. (Not necessarily in that order.)
@@pneumarian yeah! You could, but a secondhand dealer, he/she probably won’t have that information.. so basically do your own homework? Look at the video title. Ask your broker, maybe do it yourself and just look at what you know?
@@trevhedges Yeah, the broker who wouldn't try to avoid the question is rare. It definitely is a good idea never to rely on a middle-man giving good info, even if you know them to be trustworthy. "Trust, but verify."
@@normanboyes4983 nope! If I’m dropping a million down! For sure I’m doing my own homework! I think that in hindsight would have been a better video title “questions you should know the answers to before buying a boat”
Awesome video, i wish i had found your channel 8 months ago when i bought my old project cat. I have made my mistakes with incorrect materials and learning everyday. This is a great help for my planning!! No subbed and will do a binge after RTIR.👍🏻👍🏻
While three fiber materials, three resins, three cores, and four laminations give you over 100 theoretical construction combinations, in practice that is probably not the case; you would not use, for example, the most expensive fiber material together with the cheapest resin, and put it together by hand lamination. What I assume is more likely is that they would be grouped: cheap with cheap, and expensive with expensive. If this is true you would know the overall quality of the boat by knowing one or max two of the factors. Is this a correct assumption?
Definitely you would consider a vinylester boat to be of superior construction to a polyester one. This is a no brainer as the materials are used and Infused in the same way. It just comes down to cost as to which one.
I am biased owner, but according to this series, My SMG50 checks all the boxes for a true blue water cruiser when it comes to design, speed, comfort, maintenance simplicity, access, safety, material choice and build quality.
The problem is the budget : take Sirius Yacht : ultra sick monolothic hull, all bulkhead laminated to the hull, furnitured built IN the hull and so on : 450 000 for a 35' monohull. Take Amel : vinylester and glass/kevlar hull , all interior with watertight bulkhead... not far from 1 million for a 50' mono. You can do multi with all this ingredients, but what is the price ?
Brilliant! You guys or someone should put together a comparison table with all the major brands and models with all these criteria listed. It would be enormously valuable for the transparency in industry.
I watch their series as well. I like the nidacore construction because I believe it would be extremely strong and very light. One drawback might be how it's harder to flex it to curves.
this is a basic understanding , but you can ( once you have a general knowledge of fibreglass and its characteristics ) .. i would ask for the laminate schedules ,.. eg , types of foam core .. as all foams are not the same , the glass ,, is it , e glass , ,, or s glass // in this you will see for examples the layers ..of chop stand matt . 1708 biaxial matt 8oz , 10 oz.... triaxial etcetc ../ all that will be shown in the "laminate schedules " it is on the build plans . another thing .. some epoxy does not do well with fuels oil etc , (fuel . blackwater tanks)and
I love talk like this! We talked about all of this regarding Ruby Rose 2. In the end we felt that it would bore the living be-Jaysus out of most of the people watching, so left this in depth part out of the video.
@@sailingrubyrose hi nick, i think you under estimate some of viewers . i assume the foam core is closed cell? is closed cell honey comb used in any parts of RR2? bi or tri axial glass or carbon &what weights? also the bonding of the hull & deck ,antoine mentioned taping(glass or carbon & type of resin ?) as well as gluing & bonding, but adds weight!! but no comments were made in regard to extra weight versus strength in a major join. just a couple of points to clarify! ps. love the channel and as they say ,the devil is in the detail. cheers nick (
Very good video! The problem is not just the people that dont whant to know that process, the big and real problem its that the most of the buiders dont inform the byers, its incredubly insame, the nautical industry needs to change that atitude...
There was no question between sandwich properties, between balsa and foam. You said "balsa under the water line is for cost saving", so I suppose balsa is cheaper, but how really is foam better ? for structural properties, and for sea proofing ?
Foam core is closed cell which makes it better resistant to water ingress. Balsa swells when wet and this leads to a greater chance of delamination if you get water ingress. Balsa is also an organic material and prone to rot if water ingress occurs.
I had a balsa core boat and the fiberglass cracked . The balsa got wet and turned to something like weetbix ( aussie breakfast cereal) after your poor hot water on it... just turned to mush. I had to cut the whole area out of the boat and rebuild it. Lucky the area was above the water line otherwise the boat would have been on the bottom of the sea.
I'd also chime in that just as there are different core types, there are different foam types even within the category of "closed cell core foam", all with varying density, weight, stiffness, and price. Differing resistance to compression in the foam core will change the stiffness in the panel (deck, hull, etc) - part of the strength/stiffness from the fibre layers comes from keeping them further apart - if the core compresses when it bends, you'll quickly build stress in that one area and it will be the point that buckles. Think of cardboard packing boxes with the corrugations in it - it's strong, but if you give the corrugations flat, the squeezed bit becomes floppier/weaker (not a perfect analogy but there is a box in front of me, so there ya go :) )
Nick, you continually impress with your astute probing. This tech series is not only informative, it is important to all catamaran owners or potential owners. I have watched each episode with Antoine a few times over and picked up something new each time. Excellent presentation, and sorry he has to go back to work. I have about a dozen more questions I can think of for him. Thanks for the education.
A pleasure mate
Antione & Seawind thank you for making this level of expertise possible on Nick's TH-cam channel. Each show brings more questions. Your channel here has really helped the individual buyer. Bless You 😃 Merry Christmas 🎄⛄
@@sailingrubyrose Hi Nick, just to let you know that the link to the "buyers guide" you created is dead.
As a engineer with experience in these material systems, I thank you for technical explanations. I think one particular Catamaran design to understand is the deck to hull material process. Maybe in a future video you could discuss the various ways the deck is attached to the hulls.
A very good intro to a complicated topic! I know this could have gone on for hours, but I would have added some more discussion about both the varieties of sandwich materials other than foam (and not all foams are created equal) and their pros and cons above and below the waterline, as well as how much the lay-up of the GRP/E-glass/S-glass/CF in combination with the sandwich materiel affects the strength, compression, etc. (this was lightly glossed over). Builders are evolving from hand-layup to wet-vacuum to infusion as they get better financing, tooling and experience with the process, but even with the best materials and processes, lack of attention to the properties needed in specific components leads to disaster. I have been riding in pelotons where super expensive carbon bikes exploded under their riders because either the bottom bracket or the top tube were not sufficiently reinforced. I have seen foam cored skis go 90 degrees. And the latest edition of the Vendee Globe shows just how difficult construction can be even with relatively unlimited budgets and the best engineers. I am sure no expense was saved on the construction of PBR and Hugo Boss, yet obviously they were pushed beyond the limits of their materials and construction techniques. One other aspect of this discussion is the economics. Obviously, we all want the best materials and construction, but these come at a cost. What combinations are "good enough" for an ocean crossing cruiser?
Thank you for this video. I am looking at lower costs catamarans and after looking build specs they all use polyester throughout and plywood in the bulkheads. My biggest concern is osmosis.
Lagoons had tons of bulkhead failures. Not sure if it affects other budget brands. Balsa core rotting could also be an issue.
Re the discussion on hull to deck bonding, etc: I think the discussion got confused. There are really only 2 methods not three, gluing and bonding are the same thing using the same materials (epoxy or poly or vinyl ester), vs taping which applies an additional layer(s) of fiber across the joint in addition to the epoxy or whatnot.
S glass is as strong as carbon (or even stronger in some tests) but its heavier. Talking about balsa, its not just the money end grain balsa has the best bonding strength and is most resistant to debonding/delamination and has better crush resistance than foam. It's also light. The trouble is rot when it gets wet.
They say Hanse yachts suffer with gel coat crazing and the bolt on fin is vulnerable to snapping, falling off
While this series has been technical, you have managed to explain it all in a really straightforward, easy to understand way. Sharing knowledge is the cruisers mantra. That makes a huge difference to people with little experience, to gain knowledge and up skill. Well done.The concept is brilliant. i can't wait to see the build underway...
That was great Nick! (great editing as well). Really interesting break down on composite polymer construction. Sounds like there are compromises all over, but having a good knowledge of the basic processes is critical during the buying process. I think it speaks well of Seawind to freely go over all that they do. Very excited for you! Thanks again :) Franny
I'm curious why the fiberglass weave wasn't discussed, not all fiberglass is equal, and there have been major improvements in this area.
We decided to strike a balance between too much information and too basic. While the weave and orientation of fibreglass is something that interests me hugely, we felt it may be too much information for a lot of people.
I understand not wanting to complicate the discussion, it's just that the vast majority of cats are made of fiberglass and the quality of glass used is significant especially in the used market. I think an overview of this topic would be helpful for people looking to buy used.
Very useful info on materials from an experienced boatbuilder.
May I just add as a structural engineer than just using high grade expensive materials Vs lower performing materials does not necessarily give you a stronger boat.
Materials with better physical properties give you higher strength and stiffness per unit weight. They enable a competent designer to produce a high performance boat.
However, if you look at Vendée globe now you have a bleeding edge high tech boat made using top quality materials like Hugo boss breaking up and losing bits of the boat until, ultimately, retiring after 4 weeks of racing. And on the other end of the scale you still have numerous well-constructed fiberglass boats from the 1960s and 1970s still happily floating about. They are not nearly as fast but seemingly much stronger.
No they are just less stressed than a IMOCA 60 up on foils hitting waves at 20 to 30+ knots. Ooh and seeing as a IMOCA 60 weights around 8 tons INCLUDING its 3 ton keel their very lightly built !! Alex punched straight through that storm foiling which is probably what started the bow stress cracking his retirement was due to damaging a foil and ripping a rudder off.
Awesome video with a great overview! Essential for everyone who‘s planning to buy a boat (not limited to catamarans)… 🤩👍
Cheers mate. We made the video with monohull sailors in mind as well at catamarans
That didn't tell us anything about the difference between epoxy and vinyl ester. Some people have suggested there are health effects. I suppose this is due to residual evaporation from the resin.
Jeff Schionning talks about the benefits of balsa being far greater compressive and shear strength, he suggests he can use almost half the thickness due to greater shear strength and less fibre either side of the core due to the increased compression strength. So despite being about twice the density of suitable foam the weight increase is not much but the result is stiffer. This didn't mention a property of foam is that it can follow a curved form easier unlike planks.
Then prepreg carbon fibre. Given that it has to be stored and laid up in a refrigerated environment then vacuum bagged, I cannot see how it is practical to use it for even a small boat hull. Laying up a hull takes days/weeks so how would a whole shed be kept refrigerated and how would people work in it? Smaller parts and specific areas perhaps.
Didn't explain gluing, bonding and taping the deck to the hull. Gluing and bonding sound the same. Taping, wet layup of fibre across the join? Presumably even if the two halves are bonded there is still taping to cover the join if only for aesthetics.
Super informative intro to the basic ingredients. You really have a knack for working the info out and putting it into a practical and useful perspective.
FYI. Even some of us who have never been on a boat like these, won’t be buying a boat or won’t even see a boat such as these find your video very interesting. I watch several channels of travelers such as yourselves and now will pay more attention to their vessels. You and Impi bring your life’s choice to a reality level others don’t achieve. Thank you.
Nice vid Nick, although I think it's a bit quick to exempt balsa core as only chosen because of price. Working with balsa core requires the manufacturer to use a higher standard, ie: sealing the balsa where the core is perforated like thru hulls, deck fittings etc., typically, a high quality builder will remove the core in these areas. As for the wetting out due to water ingress, with the more commonly used "Infusion" methods these days, all gaps are closed off in the sandwich so that the transport of water through a damaged panel is restricted due to the fact that "End Grain Balsa" is used. In general, the resin to core bond is strongest in a balsa core panel and is generally stronger in compression and has superior sheer/ fatigue qualities. Basically, the bad rep comes from bad building practises, causing expensive repairs, like on screwed teak decks that start leaking for example. As a point of interest, in the DIY build kits from Schoinning Catamarans, the prefab Balsa cored panels are actually the strongest/lightest and most expensive option. Really looking forward to your build series and enjoy the build process. Cheers
Very very helpful. Thank you for all of your work. Can you share the buyers guide because the link in the description doenn't work (anymore).
Hi,
Just went to your discussion on electric power with the UMA crew. My takeaway is a Hybrid powerplant!
Did you address whether you want your boat gel coated or painted? You can not gel coat epoxy.
Is there any way to tell which materials and methods have been used after a boat is built?
Aluminum - over about 40 feet it is lighter, stronger, more durable then plastic, but crazy labour, all by hand
Something I know for a fact is a big ticket item for many buyers is after market structural and system customisation options for a catamaran. Some manufacturers offer this and some don't. Another good video anyway, tech discussions are interesting.
Wow! amazing video. why has no one else done such a video and it's been left to Nick and Terysa. can you do one on build contracts and should you use solicitors etc? absolutely a fantastic video. Good on ya.
A great idea using Antoine to organise and rank so many nautical and scientific terms. An excellent introduction into the complexity of yacht design and construction. I now know I am not an expert, but I have a better idea what questions to ask.Thank you Nick for a great 5 part series.
Hey Nick you drove this discussion very expertly. Your descriptions absolutely clear. Chapeau mon ami.
Great series. Thank you. And the next question: What are all the bad things that can happens to cats? (There are really two major categories here: accidents that can happen to any boat, and then issues specific to cats.) What kind of accidents, hull breaches, damage, etc? When I was building my first sea kayak I read the book 'Deep Trouble'; accident reports - all the many ways I could die in my kayak. Probably why I'm still alive after 15 years of soloing.
I wonder if it's possible, without stepping on toes, or risking being sued, to do a video on specific types of build failures, keel loses, entire frames separating from hulls, layers improperly bonded, most of these are generally monohull construction issues. There's one major brand I won't go near, including their line of cats. I don't know if I'm justified in this prejudice - but I have it. What can and has gone wrong in boat construction that maybe doesn't show up until later? So there are two categories here: what still can happen even though everything was done right? and What are the things done wrong that have made it out of the boat yard?
Watch parlay revival..
A couple questions I don’t believe where covered. How do these material hold up over time? Are some better than others? As materials improved over the last 30 years what has been the results? In terms of weight, strength, repairs?
We have a 1975 Iroquois Mk ll 30 ‘ cat. Polyester resin and fiberglass hull , polyester and fiberglass with balsa sandwich deck and cabin. The hull has been in the water for 45 years with no problem. There has been problems where water has penetrated the balsa. Had to replace the cockpit floor with foam and coosa board epoxied . Fortunately the sandwich on the deck and cabin were strong enough by themselves so that no soft spots occurred, the top layer of the sandwich was overbuilt fortunately with the exception of the cockpit floor where water penetrated and destroyed the balsa.
Unfortunatly the link is not working anymore 🥴 any chance to get the chechlist? I could‘t found on your web page. Thx!
What about core material for bulkheads, deck and the other components? I have owned boats that heavily relied on plywood. It didn't cause any issues while I owned it, but once water starts to infiltrate the wood, rot soon follows with big repair bills to fix the problems. The other thing is chopped mat vs cloth. A lot of quality difference there too.
Also substandard ply wood structural bulkheads in the Lagoons, bending and breaking without any water intrusion, causing them to sag and almost fall apart.
I think I might have OCD but please fix the middle of the 5-set of blue books... it is upside don while the other four in the set are not.. right?
Great series, thanks for the work into producing it
We use synthetic honey comb sheets between the fiber glass layers.
I follow a couple who assemble a big sail cat from premade hull materials, and they parred the two hulls with a' lenght 30- 35 centimeter wide ( looked like 18-22 cm ) hand laminated bands , about 30 layers , With poly . I asked them if they thought that would hold up in a storm , they said that floor and furniture would help , i still doubt it .
Hahaha. Say hello to our friends Matt and Jessica
I can’t seem to get the link for the catamaran buying guide to work... quite a pity, would anyone with it that happens to see this please reply?
Thanks for sharing... One thing I thought of that rarely is discussed is isolation materials. How this could be done with increased thikness of the foam core insted of doing an extra layer like a 2nd sandwich construction? Aren't there any benifits with a thicker and warmer foam core to start with? Any ideas regarding that?
Thicker and proper isolation (and ventialtion) makes the boat warmer, less condensation and even cooler in warmer parts of the world right?
balsa core is used to save weight as much as it is used to save money ... boats with a race pedigree have often chosen to use balsa in places where wisdom would suggest not to ( below the water line ) or in places on the deck which will be punctured by deck fittings - one way companies have got around some of the shortfalls of balsa is to have a grid pattern scored into the layup which allows epoxy to isolate balsa into squares ... and therefore limit water movement though coring should the core be exposed to moisture ....
I assumed the scoring was to allow the material to conform to the contours of the boat. Having watched a few videos of replacing rotten balsa, it looks like many builders are unaware of this, or just don't use enough resin to create an isolation grid.
Excellent video. The obvious statement comes to mind “You get what you pay for.” Or, at least you better - if you are paying the price. Now, cats were singled out here. I would assume the technologies apply to monohull too. Or is there a difference? Also, do most boat builders offer choices within the same models? Or is one model made consistently with the same construction? Unless you get a custom boat, you have to weigh everything from weight, size, room, features above and below deck, handling of the boat, construction materials and construction methods. If you have a very limited budget, it must be so hard choosing and prioritizing features. How do you do it? It could be the difference between going for a new boat or used one, or even a very used one.
In monohulls it is easier as weight isn’t normally an issue.
Personally if I were looking for a monohull I’d look for a pre 2008 boat. Well made and a well looked after model will take you around the world
@@sailingrubyrose Hi, maybe I missed it in the video but why would you recommend a monohull from pre 2008 and not after?
@@sailingrubyrose Absolutely agree - prior to the explosion in charter fleets and boats that are mass produced and don’t last longer than 10yrs. Even a pre- 2006 Bavaria is solid boat. Today’s mass production standards are just creating tons of future landfill..
Excellent info Nick...
2 other aspects are the stringers ( very important) and the gelcoat ...
Carbon fibre is light and strong but brittle, can be
Cracked and splintered if impacted...aluminium
Would be best but very expensive..Only Garcia make an aluminum, go anywhere cat...there are also custom builds..
Bassalt has high abrasion resistance also...it weighs more, but it costs less than Kevlar.
on lighter cats, ( one's that typically are intentionally beached ), i would think basalt would be a standard in some areas of the hulls....it's low down weight anyway.
Great video! Basic thing that the majority of people overlook when buying a boat!
Very, very good video. Extremely informative, thank you!
Well done!!! I am a material scientist and i applaud the both of you for this 'general discussion' and .....I certainly like my fiber; nicely Dry and Cake; properly Baked :)
Ah cheers mate. Thanks for the supportive words
I may have missed it, but did you discuss options for protection from lightning strikes?
Talked about it in the live feed yesterday
Thanks, this was very informative!
A pleasure mate
it' s not informative, it's infomercial.....antoine richet work for seawind......the best brand ever, of course !!!!
@@sailingrubyrose and thank you to erase my other comment, great !!!! unsub
Great video - love your technical ones
Possibly a tad oversimplification, my sympathies to the Naval Architect to be brought down to this level. However it al least pointed out some basics which I appreciate as I think your intension.
A couple of comments.
Don’t assume that a foam core won’t absorb water, there are plenty of older foam cored race boats down here in Oz that have a lot of water in the foam.
It doesn’t affect the structural strength, but it can be a weight and osmosis problem.
Secondly, epoxy is heat sensitive, which matters if you are in constant sun in the tropics, it can deteriorate and even soften if it gets hot enough.
It is even worse if the hull is coloured.
Sounds like Schionning designed cats that are pre peg epoxy are the way to go (foam rather than balsa) compared to standard production cats. Otherwise, how about aluminum in a cat 48 feet or greater? I only know of Garcia aluminum cats that are around 48 feet, otherwise a custom one off like a Mumby 48 or does anyone know of others?
allures makes some. Theres a few cat manufactures using foam. I think some seawinds and balance.
I am assuming the information here also relates to monohull construction when considering materials.
Yes mate
@@sailingrubyrose I think this is why I favor Amel. Thoughts on your former Southerly?
Appreciate the informative videos. For what it’s worth, I think the guest expert would have been able to convey greater detail if he spoke in his native language, with the translation via captions. It seemed like his responses were short simply because he was struggling to find the English words.
He did get the concept over in an understandable way however.
Very informative! Great job to both of you.
Hi Nick, could you ask about the durability of those material? What is a hull life expectancy vs boat life expectancy?
It was very clear and useful. Valid for any kind of boat, I would say, not just catamaran.
So if I'm reading this right, for the mast, you would want to potentially go with pre-preg carbon-fiber, using, at minimum, vinylester. That would give you the most strength while keeping it light (as light as a 70' mast can be!). Is that correct? Also, you would want foam with a higher density sandwiched in the load bearing sections, with less dense foam in the less critical, non essential forms, like molded furniture? Again, going with vinylester as a minimum, with a fiberglass construction. Carbon-fiber would be to cost inhibiting for the entire hull. Or are there certain areas of the huĺl where you would want it? Great job on this series sir!
Hey Nick, I could just imagine myself walking into a boat factory armed with all this information via a bullet point spreadsheet that I’ve amassed after watching all your videos concerning boat building! Do you think that they’ll shoot at me all the while I run out their door once I prod them on how they’ll build my boat!?
Thank you, Nick and Antoine. Totally informative. I even took notes!
I have delivered hundreds of yachts , cats and mono hulls from the factory. You find the creeks very quickly
I would say cats mostly , I think it's part of the job.
Nick, very intersting video series. It gives us valuable intel that we didn’t have a clue about before. Thank you for your shrudenes and altruistic sharing. Means a lot 🤝👍
A pleasure my friend. Glad you found it useful
Great discussion. Extremely illuminating!
Nick, great great stuff in this series, but now after all this info I want you to tell which manufacturers meet some or most or even all these qualities as I am in the pre stages of purchasing . Throw me a bone, when looking used which is the way to go? ( yes I have viewed your series on all the cats you reviewed ) Thanks a million the work you guys do , the entertainment and the knowledge are top notch!
Honestly mate I can’t tell you about even half of the manufacturers. I know that Outremer use foam core and even some solid fibreglass in impact areas around the keels. They also use a lot of carbon fibre.
Seawind of course as mentioned in the video and balance. The rest is for you to enjoy finding out. Don’t forget the free download to help you. Good luck
@@sailingrubyrose Thanks Nick, I knew the answer before I asked just thought I would throw it out there anyways. Much Respect!
Thanks. Super informative
What about metallic hulls?
You are the man. Exactly what I have said about the Boss Vendee glabe yacht damage.
Very interesting discussion of materials. What can you say about design? You can use the finest materials, but they do no good if there are flaws in the design. (see Parley Revival, e.g.) On the other hand, even the cheapest materials can be used to build a safe boat if it is properly designed and constructed. So, in the end, what is a buyer to do?
tried the link for the checklist - it doesn't exist
Some of the very best racing boats are hand laminated. It takes way more effort to do so however. For example if you want the very best, lightest, strongest layup the builder MUST start and ensure each and every layer is completely free of air bubbles. Excessive resin must be either removed or alternatively have the next layer of glass absorb ALL the remaining resin so that each and every layer has sufficient resin to completely wet out the glass but no more. To that to achieve the highest quality layer layups must finish only when EVERY layer is compiled fully.
Lastly peel ply should be used at the very end to enable greatest bonding properties to ,for example tape furniture decks and hull together at final assembly time.
But it must be noted that vacuum bagging at that stage has a great effect of ensuring all layers are layer up void free but also with low resin to re-enforcement layer ratios.
Good presentation. Cost is a huge consideration, for most of us anyway. I'd love to see a naval architect video on what is the best combination of compromises to build high quality, yet cost competitive, boats that middle class people can afford to buy. The marriage of quality, performance and affordability is attainable through innovation, but only if the demand is there. Hope your videos change the demand side, which could drive the supply side. Thank you!
This is a great point. Nothing in real life uses 100% of the best most expensive materials. You need to weight the trade offs and costs to build a good product. For example you could build a home that lasts a 1000 years using stainless steel exteriors, steel framing, 12 thick walls for insultation... but why do you need a house to last that long and cost that much?
thank you for these info. merci Antoine.
wow. this has been absolutely fantastic and explains why some Cats are cheaper than others
So pleased you found it useful.
Back in the day I worked on a prototype bobsled with a composite structure. Kevlar/carbon fiber mesh (6 layers on each side I believe) with a honeycomb core. Still had a fiberglass body shell, but the composite structure took the place of the tradition welded steel frame. We joked it was the only bulletproof bobsled ever built. I even rode the sled on a test run at Calgary during the Olympics there. It was an interesting design exercise.
Jamaica had a bob sled team.
@@justincruz8352 yes they did, and they were practicing at Lake Placid when we were there in late 1987 for testing.
Thank you this is very informative.
Great info about catamaran building materials, thanks. It just occurred to me while you were talking about carbon fiber boat/mast whether it would be less safe when lighting strikes or could it be more susceptible to permanent structural damage after a strike, specially at the interface of two joined carbon fiber pieces. I am assuming that's where you have a resistance to the passage of current and possibly maximum heat generated...etc
Awesome video .... very helpful... Thank you .
Good video, it would of been nice to have video cut aways for each of your topics.. just a suggestion..
Just a small comment.. pre-preg does not indicate a higher level of quality... its a time saver in the lay-up/assembly process... thats all. dry sheets of fiber are layed out, liquid resin is spread over and pressed down into the dry fiber. the now "wet" fiber is covered in mylar tape (to maintain separation of wet sheets) and then the sheet is placed in a freezer for later use. placing any resin in a freezer slows down the resin curing process and slightly extends your assembly time. it is no different quality-wise than hand lay-up.
Excellent job of gaining critical info & insight into the build! Sooner or later it always comes down to a materials expert....
The overall price diference between epoxy and venylesther would be interessting. I allways wonder way one does not want to go all the way in an investment that big.
It’s all about cost saving and because no one asks. The brokers won’t tell you their boats aren’t as well built as the one next door unless you know what to ask
Anton, I'll take a semi-pro stab at this. Epoxy vs vinyl ester is about twice the price. For a big boat, you going to need about 1000 gallons. If you look at retail for example FibreGlast quotes $2,500 per 55 gallons for vinyl ester so $50,000. For Epoxy that would be double. And manufactures can get it a lot cheaper. So let us say is half of that. So only a $25,000 difference. Does not sound like much for a boat that costs $500,000?? The real problem is epoxy is not UV resistant in its basic form. And will not chemically bound with gel-coat. So instead of applying gel-coat, followed by wet on wet laminating resin and finally finishing resin in the mold in one nonstop process. When using epoxy the process gets much more complicated, labor-intensive and time-consuming. With epoxy, you have to stop, wait for curing and then mechanically bond it to the top-coat(sanding). Or even worse hand finish after it is out of the mold. To the point that some boat builders claim the cost on the final hull is 2-5 times more for epoxy. So if you use the rule-of-thumb that the fiberglass shell is 50% of the cost of the boat and the systems the other 50%. Then the $500,000 boat now costs between $750,000 and $1,500,000 when made with epoxy. I hope this is helpful in some small way.
Aluminum? Steel? Mollen? Cupronickel? Even major manufacturers have metal models in their line up, but there is not so much info about it even on youtube. Maybe you can bright that a little on your channel?
garcia yachts makes them.
I really enjoyed the breakdown of haul and deck builds. Do you have an opinion on aluminum hauls and how they compare to the builds in this video?
So they wax the mold...spray on the gelcoat, then lay up the fiberglass layer below the gelcoat...when and how do they adapt the foam core ( or balsa) to the first layer of fiberglass ? Do they do that prior to the infusion or vacuum bag? I’m curious how they adapt stiff layers of foam core to a compound curved hull mold...great technical series.
Have a look at the TH-cam Series - Life on the Hulls - which shows where he has used different density foams adhered to the Gel Coated Fibreglass mold and where he is also building all his furniture from molds. These plus all the bulkheads etc etc are all taped into place with Fibreglass and glassed over where appropriate. He also illustrates the techniques required for molding the density foams over curved surfaces etc. hope useful. Kind regards Gavin
Tony & Susan here, Really great video series, thank you so much for the knowledge.
Hi Nick, good useful info for viewers, it's a slight shame about the choice of shot for click bait, it looks to me that it's a Mk1 Iroquois, built no later than 1970 if my memory serves me plus I'm guessing it's after a hurricane. Maybe a shot of true delimitation would have better.
Apologies for the slightly clickbaity thumbnail. As it’s a slightly dry subject we decided to “pep up” the thumbnail. The video has been live for two weeks and since we changed the thumbnail,
More people are clicking on it. I guess it is a means to an end. Btw, the previous thumbnail has the lovely Terysa on. However it seems as if a sunken boat has greater pulling power 🤣🤣🤣
Interesting, but I wonder how many salesman are actually going to know the answers to these questions,
To be honest Nick yourself and Terysa did a complete Series on Cat reviews and you never gave us any of these specs?
Kinda voided your own rating system, although i 100% don’t think intentionally, the only company i know that advertisers complete wet infusion molding inc Structural Furniture and bulkheads in Amel.
Do you see my point? Like a new car dealer if he or she is selling a volvo it’s the best car, then they move to Toyota and suddenly that’s the best car.. what would they know, they didn’t build either, they get a list of selling points provided by the companies, and if luck an independent safety rating! Not preformed under real life conditions, because all heavy 4x4s are normally rated very bad, where a tiny electric Nissan is rated excellent! If the two collided I would want to be in the 4x4 please! I think there is a direct comparison, because as i say, the salesman is not going to have a clue what weave glass was used, what epoxy or probably not even the core, but hey “look at this dishwasher and washer dryer they are standard you know” I think this series needed to be made, I believe it’s interesting ive enjoyed it. I just don’t know how helpful it will be? Probably far far less than it should..
Thanks guys!
It could force the companies into making sure that the salesmen have access to this information. & the salesmen into being sure that they know it. (Not necessarily in that order.)
@@pneumarian yeah! You could, but a secondhand dealer, he/she probably won’t have that information.. so basically do your own homework? Look at the video title. Ask your broker, maybe do it yourself and just look at what you know?
@@trevhedges Yeah, the broker who wouldn't try to avoid the question is rare. It definitely is a good idea never to rely on a middle-man giving good info, even if you know them to be trustworthy. "Trust, but verify."
would you believe anything a sales person told you?
@@normanboyes4983 nope! If I’m dropping a million down! For sure I’m doing my own homework! I think that in hindsight would have been a better video title “questions you should know the answers to before buying a boat”
Just watched the Wynns moored in a storm, survived well.
With this in mind and windage, your choice of Cat would seem to be a good idea.
Lots of good information Nick
Awesome video, i wish i had found your channel 8 months ago when i bought my old project cat. I have made my mistakes with incorrect materials and learning everyday. This is a great help for my planning!! No subbed and will do a binge after RTIR.👍🏻👍🏻
While three fiber materials, three resins, three cores, and four laminations give you over 100 theoretical construction combinations, in practice that is probably not the case; you would not use, for example, the most expensive fiber material together with the cheapest resin, and put it together by hand lamination. What I assume is more likely is that they would be grouped: cheap with cheap, and expensive with expensive.
If this is true you would know the overall quality of the boat by knowing one or max two of the factors. Is this a correct assumption?
Definitely you would consider a vinylester boat to be of superior construction to a polyester one.
This is a no brainer as the materials are used and Infused in the same way. It just comes down to cost as to which one.
I am biased owner, but according to this series, My SMG50 checks all the boxes for a true blue water cruiser when it comes to design, speed, comfort, maintenance simplicity, access, safety, material choice and build quality.
The problem is the budget : take Sirius Yacht : ultra sick monolothic hull, all bulkhead laminated to the hull, furnitured built IN the hull and so on : 450 000 for a 35' monohull.
Take Amel : vinylester and glass/kevlar hull , all interior with watertight bulkhead... not far from 1 million for a 50' mono.
You can do multi with all this ingredients, but what is the price ?
around the same price. Balance and seawinds
Brilliant! You guys or someone should put together a comparison table with all the major brands and models with all these criteria listed. It would be enormously valuable for the transparency in industry.
Yes !!! A complete comparison tool where you can insert criteria , use case (performance or lux cruising) etc ..
So much work for very little in return. People expect a lot.
Onboard Lifestle's boat Basic used Nidacore instead of foam or balsa over 20 years ago . Big cat .
I watch their series as well. I like the nidacore construction because I believe it would be extremely strong and very light. One drawback might be how it's harder to flex it to curves.
Real cool. Thank you.
this is a basic understanding , but you can ( once you have a general knowledge of fibreglass and its characteristics ) .. i would ask for the laminate schedules ,.. eg , types of foam core .. as all foams are not the same , the glass ,, is it , e glass , ,, or s glass // in this you will see for examples the layers ..of chop stand matt . 1708 biaxial matt 8oz , 10 oz.... triaxial etcetc ../ all that will be shown in the "laminate schedules " it is on the build plans . another thing .. some epoxy does not do well with fuels oil etc , (fuel . blackwater tanks)and
I love talk like this!
We talked about all of this regarding Ruby Rose 2. In the end we felt that it would bore the living be-Jaysus out of most of the people watching, so left this in depth part out of the video.
@@sailingrubyrose hi nick, i think you under estimate some of viewers
. i assume the foam core is closed cell? is closed cell honey comb used in any parts of RR2? bi or tri axial glass or carbon &what weights? also the bonding of the hull & deck ,antoine mentioned taping(glass or carbon & type of resin ?) as well as gluing & bonding, but adds weight!! but no comments were made in regard to extra weight versus strength in a major join. just a couple of points to clarify! ps. love the channel and as they say
,the devil is in the detail. cheers nick
(
Very good video!
The problem is not just the people that dont whant to know that process, the big and real problem its that the most of the buiders dont inform the byers, its incredubly insame, the nautical industry needs to change that atitude...
Excellent episode and interesting information, really like your office set up
Great series once again. Love your channel.
Ah thanks mate
u r so kind to the french guy
I would be interested to hear Nick’s thoughts on the Vaan R4/R5
Not a cute little French town but at least you had a French accent! Excellent episode.
Anyway you could just add some fresh cranberry and orange juice to make it taste better?
There was no question between sandwich properties, between balsa and foam.
You said "balsa under the water line is for cost saving", so I suppose balsa is cheaper, but how really is foam better ? for structural properties, and for sea proofing ?
Foam core is closed cell which makes it better resistant to water ingress. Balsa swells when wet and this leads to a greater chance of delamination if you get water ingress. Balsa is also an organic material and prone to rot if water ingress occurs.
I had a balsa core boat and the fiberglass cracked . The balsa got wet and turned to something like weetbix ( aussie breakfast cereal) after your poor hot water on it... just turned to mush. I had to cut the whole area out of the boat and rebuild it. Lucky the area was above the water line otherwise the boat would have been on the bottom of the sea.
Sorry to hear that mate. But confirms the point about not buying a boat that is balsa cores below the waterline.
@@sailingrubyrose Thanks for the precision !
I'd also chime in that just as there are different core types, there are different foam types even within the category of "closed cell core foam", all with varying density, weight, stiffness, and price. Differing resistance to compression in the foam core will change the stiffness in the panel (deck, hull, etc) - part of the strength/stiffness from the fibre layers comes from keeping them further apart - if the core compresses when it bends, you'll quickly build stress in that one area and it will be the point that buckles. Think of cardboard packing boxes with the corrugations in it - it's strong, but if you give the corrugations flat, the squeezed bit becomes floppier/weaker (not a perfect analogy but there is a box in front of me, so there ya go :) )