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Thread: And some of us have difficulty joining two planks together smoothly...

  1. #1
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    Default And some of us have difficulty joining two planks together smoothly...





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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Does it click into place?

  3. #3
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    And just as they are trying to squeeze it into place the foreman looks up and says, "D@mn, it goes the other way around!"

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Very impressive, on a bunch of levels.
    Steve

    Boats, like whiskey, are all good.
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Tab "A" into slot "B."
    Nosce te ipsum

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    It would be interesting to know what the tolerances are.

    Jeff

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    I would imagine that most tolerances are tight, with a lot of GD&T going on; Geometric Dimensioning and Tolerancing is an engineering technique and standard such that dimensioning and tolerancing of the part, production fixtures, and gages, reflect "true part function"; If it meets the print, it will assemble.

    However, at key interfaces, (I am guessing) the design allows some "float" after mating and final positioning before welding locks things into position.

    That's how I would design it.
    When you can take the pebble from my hand, it will be time for you to leave.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Quote Originally Posted by Bob (oh, THAT Bob) View Post
    I would imagine that most tolerances are tight, with a lot of GD&T going on; Geometric Dimensioning and Tolerancing is an engineering technique and standard such that dimensioning and tolerancing of the part, production fixtures, and gages, reflect "true part function"; If it meets the print, it will assemble.

    However, at key interfaces, (I am guessing) the design allows some "float" after mating and final positioning before welding locks things into position.

    That's how I would design it.
    Yeah I figure that thing will settle at least a little bit and change its shape as it comes off the crane.
    Rattling the teacups.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    I am in awe, not just of this, but many things man has made.

    Consider all the varieties of musical instruments and how they have to make just the right sound when played. Look at the great buildings made before we had power tools and computers, or the great bridges over wide water, or a locomotive in the 1800's. Cruise ships, etc...
    How do we form a mutiny? Our new captain is navigating poorly.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Ugly as S.
    Trust me to defend the Constitution just as soon as I'm sure you're going to vote for me again.

  11. #11
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Big deal. Iíve built PLENTY of LEGO boats.

    Peace,
    Smart E.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Quote Originally Posted by amish rob View Post
    Big deal. I’ve built PLENTY of LEGO boats.

    Peace,
    Smart E.
    Uncharacteristically snarky of you Rob.

    Setting aside the aesthetic question, the engineering, planning and building of these boats is pretty amazing.
    Steve

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    R.D Culler

  13. #13
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    I don't know about high-end aluminum superyacht structuress, but when I was responsible for designing steel superstructure modules for an offshore supply boat build, the mating tolerances were normally between 3 and 6 millimetres (1/8 - 1/4") for a twenty-ton structure that was 20 meters (65 feet) long. The modules were built in a building about ten kilometers from the hull, so popping over for a quick check was a bit difficult. I had to lay out all the plates on CAD for plasma cutting, so had to adjust for weld gaps & overlaps, and mark the plates for datum points to allow dimensional accuracy during assembly and weld-up. I also had to calculate the sag of the structure during the lift to be sure that it would land on its seatings properly. It is rather ulcer-inducing, especially when they are in the air over the hull and all you can think is, "I hope it fits, I hope it fits, I hope..."
    Hope for the best, but plan for the worst.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Quote Originally Posted by stromborg View Post
    Uncharacteristically snarky of you Rob.

    Setting aside the aesthetic question, the engineering, planning and building of these boats is pretty amazing.
    Snark?

    Maybe if I hadnít signed off the way I did, I could see that, but thereís really no way except willfully anyone could mistake my sarcasm.

    Whateves.

    I know Michael gets me, and knows I dig cool stuff well built, so Iím good.

    Peace,
    Seriously, Though, They Look Exactly Like LEGO Boat Hulls, Of Which Iíve Built A Few...

  15. #15
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Rob, the only difference between an amateur and a pro is the quantity and price of their tools...
    Hope for the best, but plan for the worst.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Quote Originally Posted by mmd View Post
    Rob, the only difference between an amateur and a pro is the quantity and price of their tools...


    One day day I hope to need a crane.

    Peace,
    Robert

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    That's very very clever. But does it mean there are a whole lot of bits that were real easy to get at in the factory, but impossible in the combined structure? I suppose the answer is yes, but you get that.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    There are always places that are awkward to get at in a ship, but generally, no; ships - even superyachts - are built to be able to be maintained. The primary reason for modular construction is speed - two crews working side-by-side complete the whole project in half the time.
    Hope for the best, but plan for the worst.

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    I was thinking of Norms (was it Norm?) pushpit, which couldn't be unbolted without creating a hole in the transom. And the unreachable and unreliable bilge pump.

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  20. #20
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Small production fibreglass yachts are built - and regulated - a whole lot differently than ships built to rules of and classed by international regulatory agencies.
    Hope for the best, but plan for the worst.

  21. #21
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    Good to know 😀

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    That's very very clever. But does it mean there are a whole lot of bits that were real easy to get at in the factory, but impossible in the combined structure? I suppose the answer is yes, but you get that.
    FWIW, my employer supplies cranes to the offshore construction industry. We’ve had two client vessels recently have the gensets overhauled by cutting a hole in the hull sides to pull them out, vessel listed for extra clearance to the waterline. Many of these vessels are on their second or third lives, having been significantly reconfigured from the original design. Fortunately steel is forgiving for this type of application - you’d be shocked how readily things are chopped and then re-welded.

    -Matt

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    Quote Originally Posted by John Smith View Post
    I am in awe, not just of this, but many things man has made.

    Consider all the varieties of musical instruments and how they have to make just the right sound when played. Look at the great buildings made before we had power tools and computers, or the great bridges over wide water, or a locomotive in the 1800's. Cruise ships, etc...
    A lot of that though, especially shipbuilding, at least until the liberty ships, was make pieces in sequence, each to fit the previous stage. Today we get big blocks of structure, all finished up to the internal partitions, even the engine rooms, wired up with all the services in place, and dropped into the assembly. Its very impressive to watch. I've heard of tolerances so tight that a section brought out from a shaded, air conditioned factory had to be left for the temperature to come up before it would fit the rest of the structure which had been sitting in the sun all day.

    John Welsford.
    An expert is but a beginner with experience.

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    Default Re: And some of us have difficulty joining two planks together smoothly...

    MMD

    About "Hope it fits"
    I used to design bridges for a high end landscape co. Arrive with the truck and off load the bridge, Client says " They didn't tell, did they". me: "Tell me what?. Seems he had asked it to be two mtrs longer. I had measured the site and designed it to span the big water feature, but not to where he wanted.
    He then told me a story about how they had shut down the entire city center of somewhere in the UK, to install a flyover bridge. As the cranes were getting it into position, it was apparent that it was a bit short.... They had sent one built for another city. Lotta egg on faces

    He got his longer version a week later, after I had a 'word' with the directors and put the fab guys on speed.

  25. #25
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    Default Re: And some of us have difficulty joining two planks together smoothly...

    AverageMatt, that procedure is pretty common. Often, there has to be too much 'stuff' (accommodations, equipment, piping, etc.) above a major piece of equipment, such as a genset in a machinery space, to allow for fast and efficient removal of it by going up, so they are placed near the shell of the ship so that a hull panel can be cut out to remove the equipment. Often the ship's structure is arranged to facilitate this. Steel is wonderfully forgiving and resilient.

    Andrew2, scary stories. My adventures with modular construction projects has, so far, been happily successful.
    Hope for the best, but plan for the worst.

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