Boat built by eye. Need feedback

Discussion in 'Boat Design' started by Nomiddlename, Jan 21, 2025.

  1. Nomiddlename
    Joined: Dec 2024
    Posts: 57
    Likes: 10, Points: 8
    Location: Kelowna, Canada

    Nomiddlename Junior Member

    Forgive me as I'm struggling to understand the regulations. Confusing wording. Here's the quote that led me to believe air chambers do not count:
    "4.4.1.2.4 Air chambers may be used to provide the necessary buoyancy if they are not:
    a) more than 0.014 m3
    (0.5 ft3
    ) in volume, or
    b) integral with the hull structure."
    I would really like to use as little foam as possible so I hope air chambers do count.
     
  2. Dave G 9N
    Joined: Jan 2024
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    Location: Lindstrom MN

    Dave G 9N Senior Member

    There is no getting around the regulations. I would read them for myself though. (Edit: I wrote this hours ago and didn't get back to hit post before you said that you had read them. Integral with the hull structure may mean that a liner or tank inside the chamber would be acceptable.) There might be some exception for boats under a certain size. Looking for loopholes. That said, pour foam runs around $115 for a 2 gallon kit so nearly 400 lb or 180 kg per 2 gal kit (feel free to correct the math).

    I have a small sailboat and have to sit on the floor. Maybe I should glue in 1 1/2 inch of XLPE foam for about the same amount of flotation and $15 more. For another $40 there is EVA yoga mat material. At least the bottom of the boat will be more comfortable. I have no idea if they can ship to Canada. (I have no connection to either company.)
     
  3. Nomiddlename
    Joined: Dec 2024
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    Location: Kelowna, Canada

    Nomiddlename Junior Member

    A foam floor is not a bad idea. Could run the tiller laying down. As for the regulations I'll have to give it a few more thumb throughs. A lot to take in.
     
  4. Barry
    Joined: Mar 2002
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    Barry Senior Member

    I was incorrect in suggesting that the ABYC requirements are the same as the Canadian requirements as far as air chamber bouyancy is concerned.
    I agree that the wording is confusing. It almost sounds like if the air chambers are
    not integral with the hull then they could be larger. Worth a call to Transport Canada
     
  5. BlueBell
    Joined: May 2017
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    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    You can try calling but you're going to end up with someone who is just as confused and frustrated as you.
    I'd hire a surveyor or Naval Architect to assist you in creating a safe boat while satisfying the reg's.
    And let's be clear here, compliance to the reg's does not necessarily correlate to a safe boat.
    Counterintuitive I realize, but sadly true.
     
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  6. Nomiddlename
    Joined: Dec 2024
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    Location: Kelowna, Canada

    Nomiddlename Junior Member

    What you say is definitely true. Obviously I need it to pass registration, but I want to build the best boat I can as well. I'll definitely reach out to a couple of boat designers in my area and see if they can do a cheap survey for me. As is true with the info I've received here in this thread, a lot of the advice I'll get I'm sure can only be implemented on my next build. Still worth knowing
     
  7. socalspearit
    Joined: Apr 2021
    Posts: 139
    Likes: 64, Points: 38
    Location: Los Angeles, CA

    socalspearit Senior Member

    In my experience narrower aft will give it better performance (resistance to broaching) in following and quartering seas but you have to be more careful with stern loading since you have the outboard already back there.

    I saw you're looking at regs and insurance. Have fun there. It's a pretty traditional build and not for commercial sale/use so I doubt you have to the small boat sink test some others were talking about. I've been dealing with stuff on my current build... The heart of the USCG small boat regs were written in the 1970's and things have changed a lot since then so they do allow for a lot of 'equivalent safeties' to demonstrate compliance, but for a small boat used NON COMMERCIALLY they'll more or less trust you to build a safe boat. If you're going by the letter on the old USCG small boat stuff you need to be really aware of the 1/5 loading rule that applies to vessels under 20' and sort of means you can't afford to put much foam, self bailing deck, or electronics in the vessel if you intend to carry more than one or two people and make the weight allowance. The old regs/tests made a lot of sense for small boats in pre-CAD days when the idea of foam in a boat was new and innovative... I don't know about your locale but what I discovered in California is that you're dealing with three regulatory bodies and they do not communicate with each other: State (for registration and licensing), USCG (compliance/safety), insurance (CYA). The state of California was incredibly easy to deal with. USCG I found also very easy to deal with and quite reasonable. Insurance has been hard for me but I have an experimental and unorthodox build intended for commercial charter use so go figure! I know you're in Canada but I'm sure Canadian coast guard will accept USCG compliant boat (or european ISO for that matter).

    The lines look nice though; I love pangas... I saw you were looking at a 6hp engine... One thing I have learned running very tiny boats in a lot of crazy weather is that as long is it's not overweighting the boat go for a big reliable engine. In the wind 6hp is probably gonna be like running in place. Another thing with small boats and outboards is power to weight, especially on the transom. What I mean is that a modern 6hp 4stroke weighs 60 lbs and has one cylinder. Go to 8hp and you have more power but your engine now has two cylinders and weighs an extra 40lbs so it barely evens out. However, if you go to 15hp - 20hp, you're still only weighing maybe 110lbs total but you're getting double the power. So when choosing an outboard go to the most available power for the cylinder configuration, which will effect weight.

    Oh yeah.. two other things... when you're reinforcing the boat don't forget to account for G-forces and pounding (I imagine you're well aware of that).

    Also I saw you built a model. That's smart and very helpful. BUT be really careful of scope creep. What I mean is that I'm assuming you loaded up your model in different ways to see how you could overwhelm it, so you could get a sense of how much real world weight you could put in your actual boat. My current build was heavily CADed, and I built a model. When I tested the model, I created all kinds of terrible loading situations--high COG, unique passenger crowding situations, etc, on the assumption that the finished boat couldn't possibly ever weigh more than 900lbs, and would likely be about 300-400 dry hull weight. Well, after building for three years and adding all kinds of stupid modern (albeit safer) stuff she weighs about 1150lbs kitted out and with a bare hull weight of 625lbs. And I was really ruthless about building light. So this is to say the boat when finished may end up heavier than you planned.
     
  8. BlueBell
    Joined: May 2017
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    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    What makes you so sure?
    We don't accept USCG compliant PFD's.

    It would be in the OP's best interest to research this on their own.
     
  9. socalspearit
    Joined: Apr 2021
    Posts: 139
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    Location: Los Angeles, CA

    socalspearit Senior Member

    Okay, OP should certainly do their own research always. It is your business to know the boating laws in your country, but a little google-foo on Canadian PFD's does not exactly clarify things...!
     
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  10. Nomiddlename
    Joined: Dec 2024
    Posts: 57
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    Location: Kelowna, Canada

    Nomiddlename Junior Member

    Thanks for the detailed reply! You've put some of my concerns regarding regulations to rest.
    Regarding structure for stiffening and foam and in general, interior layout I am cycling through about ten different ideas on a daily basis. I've attached a photo of my favored sketch. Though the idea of stringers was intended to fit a sealed floor in. This is the main idea I'm unsure about. Whether the bottom is sturdy enough with a few ribs instead.
    That is certainly some useful knowledge regarding outboards. I already have a 6hp four stroke. So I will start with that and see how it fairs with me standing at stern along with it. I'd certainly love a bigger motor to expand my range.
     

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  11. BlueBell
    Joined: May 2017
    Posts: 3,036
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    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    Are you referring to your ineffective search or mine?
    I don't need to do the search, I am a Transport Canada certified boat Captain
    and am retired Canadian Coast Guard. I know.
     
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  12. Nomiddlename
    Joined: Dec 2024
    Posts: 57
    Likes: 10, Points: 8
    Location: Kelowna, Canada

    Nomiddlename Junior Member

    Updating this thread. I brought my boat outside for the first time. Wow. I should have done that sooner. What looked good inside does not look good in the sun and from standing further back. Anywho it is a lesson. We will see how she floats but next time I build I will use a bigger shop so I can properly eye things. The sheer is still pleasing to me but the chine line is very ugly and that v is looking ever steeper. Perhaps I will paint the whole thing one colour to take away that line a bit.
     

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  13. socalspearit
    Joined: Apr 2021
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    Location: Los Angeles, CA

    socalspearit Senior Member

    You're going to always see nothing except warts and scales on your own builds unless you make aesthetics a top priority every single step of the way, and then you'll just notice ever smaller things or become so exhausted you'll never make progress... Also, at this stage you see nothing but hull and the things you dislike about it. Once there are more things on the vessel--registration numbers, outboard, whatever--they will pull attention and likely dilute your displeasure. And then add water, etc, and much of what you notice now will become invisible even to you. I think with a decently sized engine it would probably be fairly dry in a wind chop and make good headway and handle well in sloppy water; I don't have experience on windy lakes but we get various flavors of sloppy seas. With a 40hp it would probably charge through most anything. It may not have superb static stability, but you should splash it and see! I am working in the Caribbean and spending time on small, traditional local built fishing pangas. Most of the vessel have no decks or safety foam (although they have a thick wood plank core), but they'll do a big foamed fishbox about a little bit aft of midships. Green water settles into the bilge around the box, and the fish box baffles free surface effect, COG stays very low even if the boat takes on water. In weather they like to keep the bow very light and running quite high.

    I can't tell if your chine issue is paint/finish or more structural, but if it's structurally lumpy perhaps you can do more fairing?
     
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  14. Skip Johnson
    Joined: Feb 2021
    Posts: 162
    Likes: 110, Points: 43
    Location: Lake Tenkiller, Ok, usa

    Skip Johnson Senior Member

    I've lost count of the number of canoes I've designed but it was well into the double digits before I designed one that didn't whisper "I'd be a little better if.......". As has already been said, the drive for perfection destroys the good of living in the now. IMO the results of your first project of this type is remarkable, most importantly now is splash the thing and see how it preforms, a whole new world awaits.

    Of the thirty five boats I've personally built only one was "furniture quality" because it was being filmed for a video by Texas Parks and Wildlife; never again. I subscribe to the 15 to 20' rule; if it looks ok standing back a bit it really is ok. At one point building wood stripper canoes I started falling down the rabbit hole fairing the hull bottoms with an air file until I realized only the fish would see that perfection and they probably didn't care.

    One of my most memorable experiences boating was crewing with a friend on a 24' sharpie that he named 40 grit.

    I look forward to hearing how your boat performs once you've wrung it out a bit.
     
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  15. Nomiddlename
    Joined: Dec 2024
    Posts: 57
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    Location: Kelowna, Canada

    Nomiddlename Junior Member

    I do like the idea of that fish box and where it's placed. I really would love to travel more and experience more boats first hand. Most popular by far here are tinnies and jet boats.
    As far as fairing goes, I've got it into a very well lit shop now and have another week of tempuratures at ten to twenty below. So nothing to do but break the longboard out and sand. I've noticed high spots at scarf joints and fg overlaps that are doing the bulk of the damage, and lumps that look huge in the sun are really the result of smallish bumps. I'll see if I can get it right. Thanks for the insight.
     
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