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Thread: H28 "Larrikin" rebuild

  1. #1646
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    Default Re: H28 "Larrikin" rebuild

    Here you can see the bulwark not shown in the drawings but mentioned above.
    Jay

  2. #1647
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    Default Re: H28 "Larrikin" rebuild

    Thank you Jay, that’s terrific and more helpful than you could realise. I can see exactly where you are measuring and that gives me much more confidence in scaling off my own drawings. I’m also taking note of the oval capped bulwark and the effect on appearance.

    I have actually started mocking up the cockpit/aft cabin bulkhead to work out the width of the hatchway.....essentially so that I can work out the layout below it for galley, nav table etc, and will set up one of the cabin sides to your measurements this week.



    I received news yesterday that I’ve won a new 12 month contract that I’ll start in 2 weeks. Working away from home again, so I’ll probably only get another week that I can put into the H28 before it goes back under covers for a little while again. This new contract is at least a bit closer to home (about 1100km) so I hope to be back here more often than I was when working in Darwin and Perth, I’m aiming to try and get home for a weekend each fortnight.

    The upside is that it will top up my coffers for the build, both for what I need to buy for it and to hopefully allow me a clear run at working on her for a few months when I finish the contract. This last few months has been a bit stop start with other projects, distractions and commitments so I simply haven’t been able to give her the time that I’d have liked to.
    Larks

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  3. #1648
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Larks View Post
    An interesting take, I’m sorry you saw it that way Phil, it certainly wasn’t intended while trying to stop the thread being hijacked
    All good Greg, I just thought I could feel some frustration bubbling up with comments which didn't directly answer a question you'd asked, and didn't directly add to your build. I think some thread "owners" are happy for a thread to take its own course, others less so. Which is fine.

  4. #1649
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    Default Re: H28 "Larrikin" rebuild

    Greg, I am and always happy to be of service to you! LFH always coded his drawings to a list of explanations and measurements. I have no key for that so, I had to measure directly from the drawing. There is no sheer in the sides of the deckhouse. Rather just a slant. If you need the height of the coach roof beams
    curve I can have a friend measure that for you on my boat.
    I know the agony of having to be away from a boat project and can understand your reluctance to leave. But ya gotta line that wooden water pipe with money!
    Strange how money is put in one end and runs right out the other!
    All the best,
    Jay

  5. #1650
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Phil Y View Post
    All good Greg, I just thought I could feel some frustration bubbling up with comments which didn't directly answer a question you'd asked, and didn't directly add to your build. I think some thread "owners" are happy for a thread to take its own course, others less so. Which is fine.
    Any frustration sensed was perhaps more from having not asked a question and then seeing a thread about sharing a build descend into an argument about hull flexibility.
    Last edited by Larks; 10-08-2017 at 01:09 AM.
    Larks

    “It’s impossible”, said pride.
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  6. #1651
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    Default Re: H28 "Larrikin" rebuild

    Bit disappointed Greg, I was hoping for some more flash woodwork on the main bulkhead. On the other hand with you and Mal doing out-of-towners Ive a bit more chance of launching first. Spose you need money for those Velvet buttoned cushions and posh brass work.

  7. #1652
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by andrewpatrol View Post
    Bit disappointed Greg, I was hoping for some more flash woodwork on the main bulkhead. On the other hand with you and Mal doing out-of-towners Ive a bit more chance of launching first. Spose you need money for those Velvet buttoned cushions and posh brass work.
    Velvet buttoned cushions? Don’t be silly, they’d clash with my shag pile carpet
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  8. #1653
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Jay Greer View Post
    Greg, I am and always happy to be of service to you! LFH always coded his drawings to a list of explanations and measurements. I have no key for that so, I had to measure directly from the drawing. There is no sheer in the sides of the deckhouse. Rather just a slant. If you need the height of the coach roof beams
    curve I can have a friend measure that for you on my boat.
    I know the agony of having to be away from a boat project and can understand your reluctance to leave. But ya gotta line that wooden water pipe with money!
    Strange how money is put in one end and runs right out the other!
    All the best,
    Jay
    Thanks Jay, I think with those measurements now I’ll be able to gain the radius of the curves of the coach roof from the drawings.

    Re the list of explanations and measurements, are you referring to the lists in Sensible Cruising Designs that provide the detail for the numbers throughout the drawings and the sizings for materials etc? It provides: “House sides and forward end, soft pine, if painted 1 1/4” thick; if varnished, mahogany, oak or teak 1” thick."
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  9. #1654
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    Default Re: H28 "Larrikin" rebuild

    Greg, You most likely already know this. But, just in case, deck beam arch curves are not plotted as a radius of a circle but are a section of an ellipse. It is a simple matter to plot this curve but in case you are not familiar with the lofting of them, I can send you a simple explanation of how it is done. This form of arch is stronger and offers better weight bearing characteristics than a section an arc does. How ever, it is necessary to lay out individual lofting of the arcs or the center of the deck or deck house roof will end up hollowing as the sides narrow in.
    Jay

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    Default Re: H28 "Larrikin" rebuild

    I wasn’t aware of that Jay so yes please, I would be very pleased to get some instruction on this. To be honest I hadn’t worked out how I was going to find the curve - I had a vague idea that I’d do something like:
    - lay out the width of the cabin top (for each known frame -fwd of cabin, frame 14 and frame 18) on my work table and peg each end, measure the height of the arc and peg that (at centre) and spring a batten between them to find the curve -
    - cut out MDF templates for each,
    - set them up on the ground at their correct positions,
    - run battens along the length of them to simulate the cabin top
    - mark in each other frame from front to back
    - cut the cabin top frames to those curves created by the longitudinal battens.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  11. #1656
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    Default Re: H28 "Larrikin" rebuild

    I’ll be watching this too Jay because it might have some meaning for the change in cabintop on my boat too. Thanks

  12. #1657
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    Default Re: H28 "Larrikin" rebuild

    Ok guys. I will get on it. Allow me a day to get it done.
    Jay

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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Larks View Post
    I wasn’t aware of that Jay so yes please, I would be very pleased to get some instruction on this. To be honest I hadn’t worked out how I was going to find the curve - I had a vague idea that I’d do something like:
    - lay out the width of the cabin top (for each known frame -fwd of cabin, frame 14 and frame 18) on my work table and peg each end, measure the height of the arc and peg that (at centre) and spring a batten between them to find the curve -
    - cut out MDF templates for each,
    - set them up on the ground at their correct positions,
    - run battens along the length of them to simulate the cabin top
    - mark in each other frame from front to back
    - cut the cabin top frames to those curves created by the longitudinal battens.
    When my dad built his boat, he made laminated frames for the cabin top, maybe inch and a half or two inches square, maybe a bit deeper than wide. He made the forward beam first, then used that as a form for the next one and so on. There was just enough spring back in each to create a very gradual flattening from front to back. Looks just right to the eye.

  14. #1659
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    Of course each single one of us can do as he/she pleases, but somehow I was always convinced you would normally use the same curvature for the cabin-roof as you do for the deckbeams. What is left of the subject in my head right now is, that it would be more pleasing to the eye, and of course, one who is building all the deckbeams for his ship doesn't have to make an additional setup for laminating the cabin-roof deckbeams. I've never done it myself yet, so please take this info with caution!!!

    To get the curve right, what I was shown and how to do it is: draw a horizontal bottom-line and a vertical upright halfway on a piece of paper. Use a compass to draw a half-circle around where the two lines meet from one side to the other. Divide each quarter-circle in 4 equal parts, and do the same on the horizontal line on the bottom. Now connect #1 of the circle with #1 on the bottom line and so on.
    Next you need 2 measurements: the length of the widest deckbeam from side to side - this equals your horizontal line where the compass was crossing it on both sides; and you need the highest point of the deckbeam-curvature in relation to the bottom-line - which equals the line inside the circle from top to bottom.
    The length of #1 and so on gives you the height you need on this particular point etc. Draw it out full size and use a batten to draw in the line.

    Not good with explaining things, but maybe this helps you a little bit.

    There was something else I got told over and over again: The sides of the cabin need to lean inwards a little bit, otherwise it will look extremely boxy and unpleasing.

    Good luck!

    Edit: concerning springback there was also a trick to get it right, but breaking my head over it and I still can't remember how this was to be done, maybe someone else knows ...



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    Last edited by Dody; 10-10-2017 at 06:33 AM.
    fair winds, Dody

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  15. #1660
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    Default Re: H28 "Larrikin" rebuild

    I'm thinking most boats I've seen that look good have rather more curve to the cabin top than the deck. But not too much of course.

  16. #1661
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    Default Re: H28 "Larrikin" rebuild

    When I was stuck at deck beams a mate made me this diagram


    after a few false starts, i managed to transfer it to a piece of wood and it mad really nice beams....


    just ignore the bit where my circles are smaller than they should be, i had no compass and was limited bu the size of paint cans etc i had around

  17. #1662
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    Default Re: H28 "Larrikin" rebuild

    Nearly, but not exactly as it was explained to me. In your drawings the lines go in a 90ş angle down to the bottom, which distributes the curve different as the last bit of the curve will be shorter and steeper, and spacing between marks is not equal. If you divide the bottom as well into 4 equal parts, your lines from the curve go in an angle to the bottom on the initional drawing, which means you end up having an equal spacing between the different points on the top and the bottom, and the curve is even. With this kind of method you can take the heights and spacing directly out of the initial drawing, you only need to convert them according to size.
    Last edited by Dody; 10-10-2017 at 07:50 PM.
    fair winds, Dody

    "They did not know it was impossible so they did it" - Mark Twain

  18. #1663
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    I've just made a drawing, this is what I mean - the curve of course works better when you can use a proper batten and nails to hold it in place instead of struggling on a tiny piece of paper ...

    Last edited by Dody; 10-11-2017 at 08:19 AM.
    fair winds, Dody

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  19. #1664
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    Default Re: H28 "Larrikin" rebuild

    Darn! I forgot that I had a series of medical appointments that had me tied up for nearly a day and a half! I was just about to start to draw up the deck crown system of drawing and I see that Dody has been kind enough to lend the expertise for this. I like the color code choice that explains it very clearly! It goes without saying that the exact length of the beam must be correct when lofting of this.

    Just remember that each beam must be drawn separately to the same height as just cutting the width down will cause the apex of the crown to lower resulting in a hollowing of the fore and aft line of projection of the crown. From the after end of the deck house to forward as the beams become shorter as the width narrows. This causes a drop in crown height. Normally, on a deck, the rise in sheer takes care of this but here there is no change other than the straight line from aft to fwd. While this may self adjust, if the fwd beam height is chosen first, there are so few beams that I would feel safer drafting to a wire stretched between the two fore and aft points of height. Also choose the height from the after end of the beam to allow for the bevel which is constant.
    Jay

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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Jay Greer View Post
    Darn! I forgot that I had a series of medical appointments that had me tied up for nearly a day and a half! I was just about to start to draw up the deck crown system of drawing and I see that Dody has been kind enough to lend the expertise for this. I like the color code choice that explains it very clearly! It goes without saying that the exact length of the beam must be correct when lofting of this.

    Just remember that each beam must be drawn separately to the same height as just cutting the width down will cause the apex of the crown to lower resulting in a hollowing of the fore and aft line of projection of the crown. From the after end of the deck house to forward as the beams become shorter as the width narrows. This causes a drop in crown height. Normally, on a deck, the rise in sheer takes care of this but here there is no change other than the straight line from aft to fwd. While this may self adjust, if the fwd beam height is chosen first, there are so few beams that I would feel safer drafting to a wire stretched between the two fore and aft points of height. Also choose the height from the after end of the beam to allow for the bevel which is constant.
    Jay
    Thanks Jay!

    Please, I'm sorry, I know this is Lark's thread and I certainly don't want to interfere. As opposed to you I'm not a specialist but someone who tries his best to re-build his (okay, her) boat, but may I ask you something?

    It's this: initially I was really scared to get the curvature of my deckbeams wrong, so I tried to get what infos I could find and talked with a lot of people who built their own boats. Wherever I looked and talked, they were all doing their deckbeams to the same shape, and shortening them according to what they needed. At the bow, for example, the first one, will always look as if there is a hollow, but actually turns out it's not and nothing to worry about. Right, we are talking about the deckbeams for a deckhouse now, which theoretically can have any shape. If I loft each deckbeam individually as you suggest, will not the curvature of the roof of the deckhouse be different on each deckbeam which will make it more difficult to fair and lay the roof? And concerning the practical side of it, I imagine this to be very very difficult to get the height of the crown right for each single one of the deckbeams for the cabinroof. I understand there should be some tweaking going on if one wants to build an elevated cabin-house straight at the bow where the spacing is small from one end of the deckbeam to the other. But I wouldn't have expected this to be necessary amidships where the size of the deckbeams for the cabin-roof don't vary that much in size.

    Sorry again for my questions and interfering with Lark's thread, but it would be really nice if you could help me out here!
    fair winds, Dody

    "They did not know it was impossible so they did it" - Mark Twain

  21. #1666
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    Default Re: H28 "Larrikin" rebuild

    Thank you Dody and Jay for the input on this, and don’t worry Dody, your questions are equally helpful and others who may be following this will benefit as will I.

    I did try drawing up your details yesterday but got to a point where I must admit I got a bit confused, however your drawing along with Jay’s comments do clear things up for me and I hope anyone else reading.

    Using your drawing (with a couple of references added), I take it that the height A-B is the height of the top of the curve of the deck beam at the aft edge of the beam, being the very top height of the beam, also that A-F is simply the half width of the cabin at the position of that deck beam and the A-C, C-D, D-E and E-F measurements are simply the quartering of that width.

    Jay, I confess that I am still a little confused from your comments though, when you say that each beam must be drawn separately to the same height, do I understand correctly that the height used for A-B to loft the deck beams will be the same for each deck beam along the cabin top as the width of the beam/cabin narrows? And does that mean that the centre of the cabin will or should follow the same line as the sheer of the deck?

    I was thinking it’d be be flat at the centreline and the edges would follow the sheer of the deck - or is that why you say you’d draft to a wire or a straight edge, so loft the fwd and aft beams and position them and then use a straight edge to shape the rest of the deck beams between them?


    [IMG]Deck beam curve calculation by Greg Larkin, on Flickr[/IMG]
    Larks

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    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  22. #1667
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    Default Re: H28 "Larrikin" rebuild

    Ok we can get a bit further into the theory of it all here! This is the curve that I was taught to draw deck beams to. It is a section of an ellipse. This curve is stronger than a section of a perfect circle because the legs become more vertical as the height of the apex increases. It is also a section of a cone. Decreasing the width of the legs causes the height of the center height to drop greater that the projected distance between beam centers unless the sides of the ends raise an equal amount to cancel out the drop. As mentioned before, Naval Architecs take this factor into consideration when designing a sheer sweep of a deck to allow for this phenominum.

    The Greeks and Romans knew this and designed their curves to what is known as the Fibonacci curve. I might be interesting to note that this is the curve that all things in nature match into, spiral nebulae, planet orbits and radiation waves. In fact all of the proportions of the human body match to its proportions! Fractals match it and in music, the original hrz cycle of
    A432 hrz is the same cycle that the enitire universe resonates to. The A440hrz cycle of 440 hrz was adopted in 1955 as the international pitch standard. Some refer to A432 as the "God Pitch" as the say that it is the pitch that the enitire Universes vibrates to it. Oddly, taking two stringed instruments and tuning them to A440 and A432 respectively creates a resonance that places both into a level of supportive harmony. If one looks at nature, it will be found that all natural forms and sounds match to this mathematical constant to produce both beauty and harmony. Many Yacht designers, Herreshoff was one, used this "Golden Mean,(ratio) in their proportions of their designs. Herreshoff created the components of his steam engines to this ratio.

    So, the above is just a tiny bit of that which refers to this fascinating subject so far as to the reasons why the ellipse rather than the circle is used for designing deck beams. It is proven to be more pleasing to the eye and it is structurally stronger than a section of a circle. Many people will argue and many will agree with this concept just as did those who once believed the earth was flat and was the center of our solar system.

    Who can argue with that which works and works well.
    Jay

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    Default Re: H28 "Larrikin" rebuild

    Greg, if you hammer 2 nails into a board of wood, say 2 metres apart, then tie a loose string between them, then take a pencil and place it so it sits tight against the string, and trace out a mark keeping the string taut, you will draw a perfect mathematical parabola. Experiment with this, and you will be able to draw your deck beams, or at least find a constant to work to.

    They only need to be a more acute curve /camber than your deck, as far as looks go. Important none the less.

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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Larks View Post
    ... Using your drawing (with a couple of references added), I take it that the height A-B is the height of the top of the curve of the deck beam at the aft edge of the beam, being the very top height of the beam, also that A-F is simply the half width of the cabin at the position of that deck beam and the A-C, C-D, D-E and E-F measurements are simply the quartering of that width.

    [IMG]Deck beam curve calculation by Greg Larkin, on Flickr[/IMG]
    Thank you Larks for your understanding!

    And yes, you got it! Only - and I'm saying this because I'm definitely NOT a professional and need to figure these things out or be reminded about them myself - keep in mind that your deckbeams have to be fixed to your deck some way or other. If they are only as short as your cabin-roof will be wide from the inside, there is nothing left you can bolt them on to. Which means they have to be wider, but I guess you've figured that out yourself already !
    fair winds, Dody

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    Default Re: H28 "Larrikin" rebuild

    Dody, your beam is correct and exactly the way I was taught.
    Jay

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    Larks, I forgot to mention it ... I think it was Phil, not sure now, who mentioned "springback". The thing is apparently that when you laminate deckbeams, the wood still has a little tendency wanting to go back to its original form. It's not a lot, depending on the wood you are using, but you need to be aware that the final shape of a laminated deckbeam might be with 1 or 2 mm less crown or so when they have cured and you take them out of the form. Someone doing the beams for a whole boat can do a testrun to see how the wood he's using behaves. Not sure if this is worth it for a few deckbeams used on a cabin-roof.

    Not a big deal, as the same will happen with the next and the next. Not a big deal as long as they come all out of the same form and they are equal. Once you start lofting each deckbeam separately and use a different form for each single one, the outcome of the wood trying to find its shape will be different - you are not working with steel but a living material.

    However, should you get into any sort of trouble aligning them, I have managed to get things right and aligned with acro-jacks and wedges. Sure, better if they fit perfectly to begin with 😃!

    Good luck!

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    Last edited by Dody; 10-11-2017 at 07:17 PM.
    fair winds, Dody

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    Quote Originally Posted by Jay Greer View Post
    Dody, your beam is correct and exactly the way I was taught.
    Jay
    Thanks Jay!

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    Default Re: H28 "Larrikin" rebuild

    I must admit, I am finding this quite fascinating and can see that I need to put it in to practice to properly understand it.

    Jay, I didn’t realise the relationship with the Fibonacci curve or Fibonacci spiral and must now do some more reading into that. My older brother is the maths genius in our family and it seems that he hogged the available share of things mathematical, musical and electronic before I came along, but that doesn’t deplete my interest (it just means I’m a little slower on the uptake. How do you establish the golden ration in relation to the deck curve, or Is the diagram that Dody provided the basis of establishing that?

    The reason (reasons) that I’m looking at this now, ahead of finishing the fit-out, is because the fit-out of the galley and nav’ area are somewhat dependent on the height and shape of that aft bulkhead and deck frame, including the width that I will make my companionway opening (I am planning on making it somewhat oversized - but more on that later).

    And as I’ll be heading away next week for a 12 month contract 1100km away, drawing up the cabin structure ready for lofting and this area for fit out will give me something interesting to do while away from the boat.

    One thing that I am very interested to play with is how the above concept for working out the curve will compare with Lupussonic’s method with the string line, which seems very practical and simple, and my original idea of basically tillering the deck beams like a bow.



    Also Jay, a bit of an Ahaaa!/slap on the forehead moment after my first coffee this morning: I’d forgotten about the cabin sides when I posted the question above about the centre line of the cabin top being being flat with the sides curving to the sheer - would it be fair to say that the idea is to loft and cut the deck beams before shaping, cutting and setting up the cabin sides? IE:

    Loft each deck beam/cabin top beam as described above and set the for and aft beams up on a mock-up of the cabin front and aft bulkheads with a straight edge between them to hold and position the intermediate cabin top beams.

    Then template the cabin sides to the resulting curve of the cabin top beams and the existing curve of the hull at the inside of the side deck frames.


    Finally, when establishing the width of the beams before drawing them up using Dody’s information, if we are to allow a slight inward angling of the cabin sides (as I think you mentioned before Jay, or did I read that incorrectly?) do we deduct say 1/2” from the actual width of the cabin opening, or from what will be the width at the base of the cabin sides, to come up with the width to be used to draw up the beam shapes?

    And do we deduct the same amount all along for each beam or should there be an incremental decrease to allow for the tapering of the cabin sides?
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  29. #1674
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Dody View Post
    Larks, I forgot to mention it ... I think it was Phil, not sure now, who mentioned "springback". The thing is apparently that when you laminate deckbeams, the wood still has a little tendency wanting to go back to its original form. It's not a lot, depending on the wood you are using, but you need to be aware that the final shape of a laminated deckbeam might be with 1 or 2 mm less crown or so when they have cured and you take them out of the form.

    Not a big deal, as the same will happen with the next and the next. Not a big deal as long as they come all out of the same form and they are equal. Once you start lofting each deckbeam separately and use a different form for each single one, the outcome of the wood trying to find its shape will be different - you are not working with steel but a living material.

    However, should you get into any sort of trouble aligning them, I have managed to get things right and aligned with acro-jacks and wedges. Sure, better if they fit perfectly to begin with !

    Good luck!

    Sent from my SM-G900FD using Tapatalk
    Thanks Dody. I’m not sure yet whether I will laminate them of try to cut them, I’d originally hoped to cut them but am mindful of the waste in that and of what I have in way of mahogany to use for them. If I laminate them they will likely be fine laminates, probably five pieces rather than two pieces as were in place on this boat originally and which I think is what Phil described on Balia. I think the finer laminates would look better and provide better strength and considerably less springback once glued up.

    I have one particularly nice large mahogany plank that I can use, but I think I mentioned before that it feels like smashing a 50 carrot diamond into pieces to create a greater bunch of 1/2 carrot diamonds.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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  30. #1675
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    Default

    Gosh, sounds like you get caught up in the same misery to get things in the good order as gets me sometimes! Glad I'm not the only one 😃!

    I was told by several people that laminated deckbeams, especially several thin layers, are stronger than sawn ones, but who am I to know? The only thing apparent to me is that you will get much more (meaning less waste) out of your lovely mahogany-plank if you laminate your deckbeams with it. And to be honest, laminated, cleaned up and varnished looks great!

    Sent from my SM-G900FD using Tapatalk
    Last edited by Dody; 10-11-2017 at 08:03 PM.
    fair winds, Dody

    "They did not know it was impossible so they did it" - Mark Twain

  31. #1676
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Dody View Post
    Gosh, sounds like you get caught up in the same misery to get things in the good order as gets me sometimes! Glad I'm not the only one !

    I was told by several people that laminated deckbeams, especially several thin layers, are stronger than sawn ones, but who am I to know? The only thing apparent to me is that you will get much more (meaning less waste) out of your lovely mahogany-plank if you laminate your deckbeams with it. And to be honest, laminated, cleaned up and varnished looks great!

    Sent from my SM-G900FD using Tapatalk
    I agree entirely Dody and - since your post above, my reply and going back to look at my mahogany stash - I’m pretty much committed to laminating them now. I agree that they’ll also look great that way.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

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    "Keep away from people who try to belittle your ambitions. Small people always do that, but the really great make you feel that you, too, can become great!"

  32. #1677
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    Default

    How high above the deck will your deckbeams for the cabinroof come to rest? Have you figured out a way yet, how you're gonna do the attachment? Or was the system they were attached alright and you're gonna copy it?

    Curious, coz my cabin-roof deckbeams for the aftcabin on the portside are just dangling in free air, supported by some uprights with wedges banged in place and still working on a good system. They will stay like that till I've got my new deck in place ... What was there in my case was crap. And actually I haven't decided yet if I'm gonna change the roof of my aftcabin altogether.

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    Last edited by Dody; 10-11-2017 at 09:41 PM.
    fair winds, Dody

    "They did not know it was impossible so they did it" - Mark Twain

  33. #1678
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    Default Re: H28 "Larrikin" rebuild

    I hadn’t really thought that through yet Dody, but now that you ask: the original cabin sides were through bolted to the cabin side carlins with long copper bolts, i.e. drilled through and bolted the complete width (height) of the cabin sides planks from top down through the carlin that it sits on. So I’d always thought I’d just reproduce that with the new cabin sides, which I am hoping to be huon pine, and then something like a tapered notch joint to fit the cabin deck beams to the cabin sides
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

    LPBC Beneficiary

    "Keep away from people who try to belittle your ambitions. Small people always do that, but the really great make you feel that you, too, can become great!"

  34. #1679
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    Default Re: H28 "Larrikin" rebuild

    Greg, my comment on laminated deck beams and spring back was in relation to my dads boat, not Balia. Cabin beams in fact. On your comment above about the cabin sides, definitely yes they need to slope inwards, and I'd suggest by more than a half inch. Otherwise you get an optical illusion which makes them look as though they slope outwards, and a horrible boxy look overall.

  35. #1680
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    Default Re: H28 "Larrikin" rebuild

    Quote Originally Posted by Phil Y View Post
    Greg, my comment on laminated deck beams and spring back was in relation to my dads boat, not Balia. Cabin beams in fact. On your comment above about the cabin sides, definitely yes they need to slope inwards, and I'd suggest by more than a half inch. Otherwise you get an optical illusion which makes them look as though they slope outwards, and a horrible boxy look overall.
    The plans show them pretty much vertical, but as they’re only about 11” high at the aft end and about 9 1/2” at the fwd end I’m wondering how Bright Star is set up, they look vertical on her as well in photos but I have a kinda' vague memory of Jay saying they were slightly angled inwards to give that appearance.
    Larks

    “It’s impossible”, said pride.
    “It’s risky”, said experience.
    “It’s pointless”, said reason.
    “Give it a try”, whispered the heart.

    LPBC Beneficiary

    "Keep away from people who try to belittle your ambitions. Small people always do that, but the really great make you feel that you, too, can become great!"

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