Where to start?

Discussion in 'Boat Design' started by kroberts, Mar 19, 2009.

  1. kroberts
    Joined: Mar 2009
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    Location: Chicago area

    kroberts Senior Member

    Hi folks.

    I am interested in building a sailboat, but have no experience with boat building.

    I have the following experience:
    1. I was raised around boats, mostly flat-bottom aluminum "canoe resort" canoes, fishing boats from 12-18 ft made of aluminum or fiberglass, that sort of thing. This is from my youth up till my early twenties, and then again later from 30-35 or so.
    2. I have had a UH-12r hovercraft bought used and maintained repeatedly. This is a stick and plywood hovercraft made with epoxy and fiberglass to join the seams. This started about the time I stopped playing with boats.
    3. I have built a UH-18sp hovercraft from plans, and it works as advertised. This is a foam and plywood craft made with epoxy and fiberglass at the seams.
    4. I have been in a small sailboat several times as crew in the last couple years, not sure what type it is but the person who took me out called it a "420." It had a centerboard and 2 sails, the main sail and what I think you call a jib, which was attached to a front cable from the nose to the top of the sail, and you tied it to one side or the other depending on where the wind was from.

    I want to learn about best practices, building techniques and technologies without pestering you guys about it. I'm looking for recommended reading.

    I think I want to use modern materials and techniques. I would like to try my hand at vacuum infusion, but this might not be the project for it. I have the vacuum pump, an IR with 32 CFM and 29" mercury. I would consider building a post-cure oven as well.

    I think the boats you guys are making are beautiful, but I have doubts that mine will be so nice. I have this tendency to make it functional and then get in and drive. I don't think I could do the varnished wood thing and pull it off like the pictures I see here.

    I also have this thing for speed. I don't need anything outrageous for my first boat project, but I think something that goes at a significant rate would be a good starter. I am attracted to catamarans and single-hull designs both, but mostly something that can be put on top of a car for now.

    I currently weigh 250 lbs, and I think it should be able to carry another "me" as well, so 500 lbs payload or just me. Something that can be set up and broken down by one guy. I would hope very light weight, sturdy, some sort of composite.

    Fresh water mostly I think, I live near Chicago and there's this big puddle to the east. However, it would be good to have it able to go on salt water.

    I've been in powered watercraft for years now. It's time to try the other thing out.

    There is no real big hurry here. I can easily spend the next year picking my design and my technology. I don't need to do it all the hard way, and I don't need to design it myself. I just want a starter kit for somebody who has built things but not boats, and which gives me moderate weather handling and moderate speed.

    And, as I said above, I am currently looking for reading material on building techniques, best practices, current maritime law and maybe some interesting boat designs, all using Mother Nature as the motive force.

    Thanks.
     
  2. apex1

    apex1 Guest

    Hello mate,

    I think the payload of 500lbs and the car top issue will not go together. Is´nt a trailer within the range?
     
  3. kroberts
    Joined: Mar 2009
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    kroberts Senior Member

    A trailer would be in range, but I was hoping to avoid the "yet another trailer" problem.

    I would consider a 16 foot long catamaran, there was a plan I saw here:
    https://www.boatdesigns.com/products.asp?dept=456 which seems to imply a car-topper. It doesn't say how much payload, but does say 2-4 people. I don't know the quality of that design or how to judge it, and I don't really want to do plywood again.

    My neighborhood they want you to store everything inside unless it can legally drive down the road under its own power. Trailers, in other words, must be stored inside.

    That said, a light weight frame trailer that I could either load the whole boat up on or break it down like a car topper, that would be fine because I could probably get the boat home, break it down, put the parts in the garage and then maybe hide the trailer behind the garage. I don't like trailers that disassemble.

    It would be neat if I could get the boat in my basement. It's an old house, got the 100+ year old basement with the uneven concrete floor and all that. My house is empty, my garage is full. :confused:

    Thinking about it, a kayak or canoe would also be interesting and probably more logical for a first-time project. I still want to consider sails of some sort.
     
  4. apex1

    apex1 Guest

  5. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    There are a lot of designs to choices out there, from wholesome, stable daysailors to scare the crap out of you rockets, that easily can get you over 25 MPH, with your butt a just kissing the wave tops (literally) and spectacular crashes a regular occurrence.

    Somewhere in between I'd suspect, particularly for a novice sailor and a limited experience builder.

    I know you want to stay away from wood, but you'll find the alternatives not nearly as pleasant to work with and frankly, it's very difficult to match the physical properties of wood in other materials, without using high tech fabrics and techniques (read lots of money).

    Considering you're likely sailing location, general crew weight requirements, you'll probably need a fairly wholesome 15'er or a well thought out 17'er. A popular 17' day boat is the B&B Yacht Design CS-17. It's fairly stable, fairly fast, fairly easy to build and a large network of other builders to share you issues, questions and construction woos with. I've just completed one for a client a few hours south of me. Although I made extensive design alterations, which increased build time, the basic boat is pretty straight forward.

    In this size range, there are literally hundreds of designs to choose from, including a few that I offer. I'm about to build a 15' rocket, masthead Bermudian rigged, with a semi rigid foil luff, rotating mast, square topped main, etc. It's one of my "prove of concept" ideas and should prove very fast and close winded. Probably a bit much for you, but the rig could be an upgrade on another design.

    In regard to alternative building materials, the selection boils down to metals (aluminum, in this size range) or some sort of 'glass build. Metal is an option, particularly if you're a good welder. The choices for this type of small boat will be quite limited, but some are available, again including an 18' aluminum ketch I designed a few years back.

    'Glass is an option, but there are many ways to apply it. In one off applications, you can employ several build methods. Once more the choices will be limited as it's not a material that most novice builders feel comfortable with. Another consideration is how much skill it requires to get a smooth hull, from goo saturated fabrics.

    Look at design offerings from:

    www.Glen-l.com
    www.bateau.com
    www.duckworksbbs.com/plans

    These will get you started. You'll find most are for wood and plywood construction, frankly because wood is pound for pound stronger then steel, but there are several 'glass builds as well.

    In the end, you'll spend a lot of time looking for the right design. You can just as easily build a boat that you'll hate to sail, then one you'll love, so look long and hard before making a decision.

    Analyze your desires, make lists of these needs, wants and just got to haves. Find the design that addresses as many as you can, in a build method that suits your skill sets and wishes.
     
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  6. apex1

    apex1 Guest

    Sic........................................
     
  7. kroberts
    Joined: Mar 2009
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    Location: Chicago area

    kroberts Senior Member

    Par,

    Thanks for the reply.

    Maybe I need to be a bit more explicit about my skills.

    Welder: I have a cheapo MIG welder. I can't weld aluminum with it. Technically I can but I can't attach a spool gun to it, I have to push it all the way through the tube. Heard about the trouble, won't even bother. I should have spent twice as much and got a pro-quality welder. I am not a good welder yet, but I have a professional who is training me every now and then.

    Fiberglass: I have done lots of this, more than most home builders. I've taped plywood structures for years, I've fabricated one-off parts, I've popped parts off a mold and I've helped build molds. I've used vacuum bagging, but so far not the hard vacuum process, mostly so far just to keep the fabric laying flat on a complex structure.

    I know about air filtration for breathing, and the need for good ventilation and explosion-proof equipment when using infusion. I've done a LOT of reading on this.

    I have a 32 CFM vacuum pump which can get to a 29 INHG hard vacuum. If I were to build a hovercraft, it would be with something like PlasCore or CoreCell, and I would inevitably get that vacuum pump involved somehow. I am fascinated by vacuum infusion. I was going to use that pump to make a hovercraft hull of my own design with vacuum infusion, including making molds and possibly learning about post-cure ovens too to get the weight low. I have about half the gear needed to do vacuum infusion, price-wise, but nothing for the post-cure. Note that everything in this paragraph is a "want to" not a "have done." I do not know much about vacuum infusion resins but I am infinitely familiar with Epoxies like West System, System 3 and RAKA. There is a new brand called Epoxical that will be tried next.

    I have built my own wooden hovercraft props and glassed them, worn them out and repaired them.

    Things I had in mind for materials:
    Plascore, CoreCell or some other non-foam structural composite.
    Fiberglass or possibly Kevlar/Carbon.
    A new try at an infusion resin, which I would still have to learn about.
    I am not afraid of making a mold, though I have never done so for anything larger than 6 feet across.

    This is a far-advanced query. I am not ready to even look solidly at plans. I was more hoping for some books to read about best practices and building techniques and what type of boat does what. And for that matter, what all the words mean.

    The more I think of it, a catamaran is most often the image in my mind.

    I am not a novice boat user, but I am a novice sailor. I am a novice boat builder, not ever having built one. But I have built or helped build several hovercraft.

    That said, I can see how my first boat might be a wood hull because that's what everyone uses. I know I have a whole lot to learn about sail boats, and about boat building in general.

    I would want a boat which a novice sailor can learn, but if it's twice as hard as learning a normal starter boat then that's OK, if it will really kick it in gear when I learn how to fly it.

    Thanks for your help.
     
  8. kroberts
    Joined: Mar 2009
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    Location: Chicago area

    kroberts Senior Member

  9. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The CS-17 has a multiple role design brief. Her original intent was to be able to row and sail well in rough, broken water. This means top speeds under sail are not as high as they could be, say if the hull was optimized for planning performance. She also has more freeboard then would be typical of more performance oriented craft. Conversely, she can handle deeper and rough water then a typical performance dinghy, she can be rowed easily, which a planning dinghy doesn't do well at all. Another aspect is the cat ketch rig, which many find desirable, particularly if your sailing skills are limited. It's a forgiving rig, has hands free tacking and modest running rigging needs. As far as speeds, I've had them in double digits, but the average sailor will generally see 8 knots.

    Alex's Rocket will be fairly easy to sail, but if you want her to kick up her heels and scoot, then you'll need some skills, likely a trapeze and not be afraid of capsizing the puppy. Flying a balloon and getting the most out of her rig will require sail set and handling skills.

    As a rule, the faster you want to go, the more skill you'll need to handle the boat (keep the decks facing up).

    Multihulls can offer a performance gain, but usually at a load carrying limitation, compared to similarly sized monohulls. They also, being much wider, will be more difficult to find space for without having to disassemble the beams and stack the hulls.

    If you want to try infusion methods you can adapt for this, though I think you'd be better off with plain old vacuum bagging techniques, for a one off hull. Unless you have deep pockets (real deep) Kevlar, carbon a graphite should be discounted. Some parts maybe, like spars, but these materials are quite costly compare to more conventional means. I don't think a novice sailor will appreciate the advantages of these materials without considerable time at the helm.

    You could start out with an "intermediate" boat, which will offer the ability to "power up" as you skill levels increase. If you jump in the big end of the pool as you first boat, you may find getting dumped in the drink is you best sailing skill. You see, the upper end performance sailboats will reward a mistake with a quick, usually violent tossing of it's skipper in the wet stuff. This isn't the best way to learn the skills you'll need for these types of boats.
     
  10. kroberts
    Joined: Mar 2009
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    kroberts Senior Member

    Par,

    I started that way with my first hovercraft. Never learned to drive the slow ones until much later, and found I couldn't keep up in a race with members of my own class because they knew things I hadn't learned.

    I was dumped in the water once sailing, we had a blast. Got it back together and did it again. Not afraid of that, but I am afraid of falling out and having the boat take off for parts unknown without me. I can definitely see myself going out on Lake Michigan after a year or two of practice, meaning not just hugging the shore locally but maybe head for the other side. Not sure if that's feasible with these boats, but it would be the sort of thing I would find very fun.

    Most of what you're saying here I figured were probably true, the skills and high performance machinery is the same in any type of vehicle.

    The "intermediate" idea is definitely what I have in mind. Although, if that 15' rocket is even remotely possible it looks intensely interesting to me. Can it be rigged such that a single guy can sail it? Is it too small for my 250 lbs and maybe another 250 lbs as crew? Or do we each have to have a separate one? :D

    The more I think of it, the more I think the first one will be wood. These prices are in my range, and I know the wood part. I could probably go a bit better with some of it, but as you said a pure carbon or kevlar boat would be a very expensive venture. I don't necessarily buy into the wood idea for boats, but there has to be something interesting for next time.

    That said, some of these boats are incredible to look at, I personally wouldn't dare take these heavily varnished things out on the water for fear of hurting it.
     
  11. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    The boat I just finished was varnish (okay, clear LPU) from the sheer line up. I have no trouble taking out a boat like this, particularly with the newer, hard, clear coatings available.

    My little rocket is really a one man boat. It could handle you, but crew, not so much, unless it was kids (I calculated 340 total pounds for crew). It's a proof of concept deal so I'm making economical use of 8' plywood, hence the length just over 15'. It's also quite narrow, making for an easy to propel boat, but one that is also not especially stable. She'll claw upwind like a monster and has little to hold her back going down hill. It's not a boat for the novice and I'll be tested continuously underway. It easy to break stuff on boats like these when you "auger" one in, so it's not a recommended boat unless you can handle a hot dinghy on a trap with an asymmetric, sailing solo.

    I've sailed the big puddle to the right of Chicago and it's not a lake you want to cross without a well equipped boat and with a good amount of deep water experience. A planning dinghy would be easily overwhelmed, so would a beach cat. This isn't to say a well seasoned skipper could cross it, but they'd need some luck and excellent seamanship skills. That puddle has taken it's fair share of professionals, so amateurs should heed the wrath of the ghosts on the lake. A skilled skipper in a CS-17 type of boat would fair well (better if a CS-20 or EC-22), but this is one of the things the Core Sound series was intended for. Sailing a performance dinghy across would be just asking your wife to collect insurance money.

    You could build a cored boat, especially with your 'glassing skills, maybe a way to go. Most plywood designs can be converted to alternate methods, but it's understandably wise to get professional assistance for this task.
     
  12. kroberts
    Joined: Mar 2009
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    kroberts Senior Member

    Par,

    Thanks for the warning, and it will be heeded. What about following the coast around?

    No matter what, I would be sailing just locally until I know how to handle the boat. There are other sailors around, and I can talk to some of them for advice. There is also a course an Northwestern University I can take, I would probably do that while building the boat. They let you use their boats for the summer if you take the course. They appear to be similar to the Alexa's Rocket but with a more rounded hull. Sails are very close to the same configuration. These are the "420" boats I mentioned earlier in the thread. Very fun, probably much easier to sail than the rocket, probably much slower although they do race them.

    If I went with a varnished boat, I would want something that was not plywood. Two different things, right? A show boat and a play boat. I don't have enough room for that.

    On the other hand, if it were between a CS17 or a CS20 I don't think it matters to me much. Same amount of trouble to store either one, basically the same space since it's a slot in a garage. The EC22 is a little big I think, I'm also not really into the cabin idea. I more think the helling around toy, that I could possibly use as an overnight type deal.

    My idea of camping is leaving the car behind and putting everything you need into a backpack. When hovering, I do the same thing but put the backpack into a dry-sack such as those used in kayaking. No kitchen sink, and usually not even a fire or tent.

    What type of cores are used on cored boats?

    Thanks.
     
  13. apex1

    apex1 Guest

  14. kroberts
    Joined: Mar 2009
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    kroberts Senior Member

    Richard,

    That explains a bunch.

    Do you have any favorite core boats I could look at?

    I'm still kinda stuck on a catamaran, up to probably 20 or 22 feet. If I can do that, I can break the boat down and bring it into the basement through the cellar door for storage, and leave my garage for tools and cars and my hovercraft.

    None of the processes I've seen mentioned here on this site bothers me at all. Lofting, any of that. I might not be great at it at first, but I have no doubts I can make them work. I have a lot more tools than most beginners would have, and some experience building other things besides boats. Usually you don't have to twist my arm much to get me to buy a tool.

    I do not mind being dumped in the water, but I don't want to have to fix my boat every time until I learn how to fly it. Some risk is OK, but not continual repairs every time I go out.

    I do not mind taking plans of a boat and scaling them up to get a larger boat, especially if I could convert it from wood to a core boat in the process. That will be labor intensive, but it's labor before the build, so to speak, and on paper.

    Case in point, if I could take the Alexa's Rocket and make it into a 17 or 18, while making it out of NidaCore or Divinycell, that would be great. I'm more interested in a thermoplastic honeycomb rather than a foam.

    The scaling part, I know I can handle. The building part, I know I can handle. What I'm not sure about is for these S&G boats getting the parts to be exactly right, much is made of the need to be exact there. I understand what needs to happen, but not how exact it must be without gross deviation from the wanted shape.

    Can one "test drive" an S&G hull? Stitch it without gluing first, to see how it works out? How about stitching the whole thing and then gluing?

    Thanks.
     

  15. apex1

    apex1 Guest

    To start at the end: no... "test drive" is´nt possible. The glue step gives the structural stability.

    To scaling: that is usually not possible!!! One cannot scale a given design up or down.

    To the substitution of one material by another: some designs work fine with the strip plank method in either wood or foam. But usually the specific properties of the designed material is part of the NA´s calculation and cannot be substituted.

    There are just a few "homebuild" designs using honeycomb cores. (I do´nt know just one).

    To the catamaran question: I have absolutely no idea what a cat is, I am the absolute layman in that field.

    But again I would like to wait for Paul, he must not translate his thoughts, as I must, and he is more familiar with the designs available on the market.
    Regards
    Richard
     
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