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Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
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Author | Topic: SCIENCE: -- "observational science" vs "historical science" vs ... science. | |||||||||||||||||||||||||||||||||||||||
RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
... The one on the right is constructed of small beams relative to length connected by innumerable small pieces of wood creating a huge number of joints. ... You *know* this how? The posts supporting the hull are ~1/2 the length of the boom ...
The boom in the left image is constructed of two massive beams relative to length and with no joints, and it has support both at the top and in the middle. ... The overall thickness of the one on the left actually looks thinner than the one on the right ... to me. You see the A-frame because it is not in profile like the one on the right ... and you are seeing a diagonal of the boom rather than a side view ... The purpose of showing the one on the left is that the lighting used to show the "two massive beams" can also be interpreted as them being composed of double booms with a top and a bottom and a gap between them ... just like the ark boom picture can also easily be seen as a "massive beam" with the side lit up by the sun low to the right ... except (of course) where it is in the shade of the hull. Given the reasonable doubt involved, I would assume a simple A-frame gantry and mast being seen in profile, as there is documentation of that geometry being used in ancient times. The line from the mast to the tip of the boom could be used to raise and lower the boom, while the line just above the boom could be used to raise and lower the load. The more vertical the boom is the less it is likely to be affected by bending due to its own weight (the ONLY side load). On the other hand, if you insist on interpreting the picture as having top and bottom booms then THIS picture was provided to you as an example of how that could be done:
The cross-bracing between the sides of the A-frame (you can't tell if it is there or not) prevents side buckling and the ends form cross-blocks between the top and bottom ... and this lowers the effective kl/r. Just because you *think* the beam is too small for the length does not make it so. There are many many many things that "common sense" gets wrong, but on this forum I would hope that claims that something obviously can't work would be supported by actual evidence that it can't work. Wood is naturally stiffer than metal for the same weight. That means calculations, and that you need to do them to support your claim (and maybe learn something?) Now as far as I am concerned this particular argument is like pissing into the wind ridiculous as a critique of the possibility of an ark actually being constructed. What I am concerned with is the intellectual honesty to use empirical evidence and basic (scientific ) knowledge to demonstrate the reality of a claim. Call me a devil's advocate on this issue, but I don't think an argument based on opinion is valid, no matter who makes it. I'm not saying an ark could have been built this way, I am saying that you haven't demonstrated that it can't. Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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jar Member Posts: 34140 From: Texas!! Joined: |
There was Noah and his three sons but they had 120 years to build the sucka. Noah was almost 500 years old when they started.
I doubt a crane would be needed. The easy way would be to build a sand ramp instead and let the rain wash it away. Still, with just four worker bees even a 120 year schedule requires some flat humping.Anyone so limited that they can only spell a word one way is severely handicapped!
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Percy Member Posts: 22934 From: New Hampshire Joined: Member Rating: 6.8 |
RAZD writes: ... The one on the right is constructed of small beams relative to length connected by innumerable small pieces of wood creating a huge number of joints. ...
You *know* this how? The posts supporting the hull are ~1/2 the length of the boom ... As with Ringo, I'm again beginning to wonder if we're talking about different parts of the image. I've been talking about the boom and just the boom. I've circled a section of the boom that contains many of the cross members I've been referring to:
The boom in the image looks like an attempt to mimic in wood the lattice of the boom of a modern crane like this one:
This kind of lattice made out of wood would crumble into a pile of matchsticks.
What I am concerned with is the intellectual honesty... Really? --Percy
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RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
As with Ringo, I'm again beginning to wonder if we're talking about different parts of the image. ... What Ringo and I see as a reasonable assumption is that if you looked down on the crane you would see an A-Frame shape -- this is a very common very old structure used to hoist objects and is still used in construction today because it is simple and effective. This arrangement protects against side sway with a swinging load, while fore and aft sway is countered by the crane being in line ... and whatever keeps it from toppling forward or backward (hence the cables leading to stakes in the ground in the other pictures). Curiously, I would be way more concerned about toppling than about the boom buckling. Those counterweights can only be so heavy before they cause the unloaded crane as shown to topple backwards, and that then limits the maximum load that can be lifted with the boom extended before it topples forward. Modern crane operators have charts of extension vs load that are safe to use with the legs out. This does not have legs for tipping support (which it would have if they were mimicking a modern crane yes?) But it is rather silly imho to argue about the reality of the crane until Hammy actually makes one and uses it, don't you think? He will either be using the benefit of some observational science in the design or he will be actually doing some observational science to make it work. He's already been forced to compromise his design by having concrete stairwells for fire protection ...
... I've circled a section of the boom that contains many of the cross members I've been referring to: The boom in the image looks like an attempt to mimic in wood the lattice of the boom of a modern crane like this one: What I see are pixels not cross sticks, and where the cable to hoist the load gets to the same distance from the top (see just inside your circle upper intersection) you see the *same* pixel connections ... are those also sticks? Or is the white strip just a highlight used to show the sun shining on the boom? Is the cable made of short knotted lengths as well? And why does the bottom of the boom look like a massive solid boom? But I don't really CARE what you think is the proposed construction, as I've also shown you an alternative A-frame that had top and bottom elements to each side boom to give you the image you want to see. It would look like what you claim from the side but without any cross struts ... What I CARE about is that you have not done the calculations to actually *SHOW* that your vision of the boom structure would fail.
This kind of lattice made out of wood would crumble into a pile of matchsticks. Show me: do the calculations, show your assumptions (loads, yield strength, modulus of stiffness, etc etc etc). What do you end up with for the maximum safe lifting load?
What I am concerned with is the intellectual honesty... Really? Yes: do the calculations: show me Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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Percy Member Posts: 22934 From: New Hampshire Joined: Member Rating: 6.8 |
RAZD writes: What I am concerned with is the intellectual honesty... Really? Yes: do the calculations: show me If you assume the cross members are actually just image artifacts that aren't really there, and that the boom is actually an A-frame that isn't in the image, then of course my objections disappear. But you only just now introduced these possibilities, and your questioning of my intellectual honesty is inexplicable and hurtful. I thought we knew each other better than this. But anyway, let's shift to the higher resolution image I found:
I see no A-frame. I see a boom consisting of two parallel and unconnected beams. --Percy
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Coragyps Member (Idle past 984 days) Posts: 5553 From: Snyder, Texas, USA Joined:
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I see a Dalek dressed up for some really odd Mardi Gras parade.
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Tangle Member Posts: 9580 From: UK Joined: Member Rating: 6.6
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I see a a wheeled vehicle that will tip over either forward or backward if the load and counterbalance is is even slightly off balance.it's intrinsically unstable.
Life, don't talk to me about life - Marvin the Paranoid Android "Science adjusts it's views based on what's observed.Faith is the denial of observation so that Belief can be preserved." - Tim Minchin, in his beat poem, Storm.
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William Rea Junior Member (Idle past 2871 days) Posts: 12 Joined: |
Hey, it's your 'thought experiment' that you decided to take into fantasy and you're busting my balls over your paradigm that I was going along with for the sake of argument? I have nothing else to go on so I assumed that a C18 wood soft enough to work from here...
Timber Design Index - Roymech ...was a starting point considering that we might be talking about a 'solid block' but that it would need to be hewn to make a container in which case we would need to adjust your section moment OR I am happy to assume a stronger D30 material for a viable subframe with a C18 cladding in which case your model becomes inadequate even as a fantasy thought experiment. My statement may have been 'bald' but, I obviously made the point about your 'literal interpretation' far too subtly so I will be more forthright. It is fine being a philosophical smart ass and saying that you can conceive of a solid block of wood of those dimensions and do a simple calculation in your thought experiment. Great but, being literally a philosophical smart ass back at you, assuming the solid block can be made from numerous trees how does a solid block function as a boat? It floats but it is not a boat as the term is generally understood unless you can convince me otherwise? The statement was made in the knowledge that it is generally agreed upon that practical wooden boats over 100m are at the threshold. In this particular case of the Ark Encounter 'classic' design, a wooden boat with no means of steerage has no way to protect itself from swells and waves breaking across it. You can argue, if you like, that the flood could have been pond like and so a boat drifting with no visible keel or steerage (exactly as pictured in the Ark Encounter literature) would not need such. Regardless, modern wooden boat manufacture halted for many reasons at around 100m length mark. Finally, I will accept as evidence that previous attempts and this attempt will require sub-structures on land and/or afloat to make it viable and, it could be argued that modern H&S requirements mean that less risks have to be taken but, that indicates that quantitative risks exist with such a structure. At the same time I will accept that because it has not been made, that does not mean it cannot be made.
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RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
But anyway, let's shift to the higher resolution image I found: Like the one I found on Panda's thumb ...
I see no A-frame. I see a boom consisting of two parallel and unconnected beams. Because that's what you want to see, and I previously showed you that their could be two parallel beams on each side of the A-frame with this type of construction:
... from the SIDE ... so you are looking at the EDGE of the plane the A-frame would be in ...
If you assume the cross members are actually just image artifacts that aren't really there, and that the boom is actually an A-frame that isn't in the image, then of course my objections disappear. But you only just now introduced these possibilities, ... See Message 583 ...
But anyway, let's shift to the higher resolution image I found: Indeed, and now look at the outer end where the pully is that the lift line runs over and where the line controlling the lift of the boom is attached:
Inquiring minds want to know. Again, if I were going to criticize this concept I would look at the small base and the heavy cantilevered counterweight at the top -- a very top heavy small stability base concept prone to toppling imho. This looks like something you would see in a fantasy warcraft type video game, by people with no clue to the engineering of a crane, rather than any imitation of a modern crane imho.
... and your questioning of my intellectual honesty is inexplicable and hurtful. I thought we knew each other better than this. Sorry, but you made a claim that the boom would be too flimsy and would collapse. All I have asked you to do is make the calculations to show this, which you have resisted doing so far. Curiously I am not convinced by opinion, and without the evidence you have made your case -- you have not provided the evidence to support your claim. Enjoy Edited by RAZD, : .. Edited by RAZD, : subt Edited by RAZD, : finishedby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
Hey, it's your 'thought experiment' that you decided to take into fantasy and you're busting my balls over your paradigm that I was going along with for the sake of argument? I have nothing else to go on so I assumed that a C18 wood soft enough to work from here... http://www.roymech.co.uk/..._Tables/Timber/Timber_index.html ...was a starting point considering that we might be talking about a 'solid block' but that it would need to be hewn to make a container in which case we would need to adjust your section moment OR I am happy to assume a stronger D30 material for a viable subframe with a C18 cladding in which case your model becomes inadequate even as a fantasy thought experiment. My statement may have been 'bald' but, I obviously made the point about your 'literal interpretation' far too subtly so I will be more forthright. It is fine being a philosophical smart ass and saying that you can conceive of a solid block of wood of those dimensions and do a simple calculation in your thought experiment. Great but, being literally a philosophical smart ass back at you, assuming the solid block can be made from numerous trees how does a solid block function as a boat? It floats but it is not a boat as the term is generally understood unless you can convince me otherwise? You are overthinking the problem. The purpose of the single block was to show that such a structure would not break in waves that matched the length of the ship, even using a simplified calculation that gives higher stress than a ship would actually experience (there would be partial support along its length rather than point supports -- the USCG has a formula for modeling this). So if we can agree that a solid block would not break up, and that one with just a thin shell would, then all we need to do is find where we cross the line ... but it should be obvious that some intermediate forms would work, so a blanket statement that the ship would break up is unfounded.
The statement was made in the knowledge that it is generally agreed upon that practical wooden boats over 100m are at the threshold. In this particular case of the Ark Encounter 'classic' design, a wooden boat with no means of steerage has no way to protect itself from swells and waves breaking across it. You can argue, if you like, that the flood could have been pond like and so a boat drifting with no visible keel or steerage (exactly as pictured in the Ark Encounter literature) would not need such. Regardless, modern wooden boat manufacture halted for many reasons at around 100m length mark. ... The critical length for vessel strength is when the wavelength matches the hull length: under that the hull is supported on closer wave crests and has less stress; over that and the surface the vessel is interacting with is more pond like. At around 2 hull lengths the shape in the wave trough gets pretty flat by comparison. With no steerage the hull will be turned sideways to the waves (because of the way the water moves in a wave) and will then sit in apparent level water. In usual storms this is dangerous because breaking waves can roll the hull. This could be controlled by towing sea anchors or long cables, but I see no reason to assume their existence.
In this particular case of the Ark Encounter 'classic' design, a wooden boat with no means of steerage has no way to protect itself from swells and waves breaking across it. You can argue, if you like, that the flood could have been pond like and so a boat drifting with no visible keel or steerage (exactly as pictured in the Ark Encounter literature) would not need such. ... What I would argue is that with no land, the "fetch" for the waves is essentially infinite so the wavelengths would be very very large and probably sync with the tidal waves. Do you know what a (tectonic not tide) tidal wave looks like in the open ocean?
The statement was made in the knowledge that it is generally agreed upon that practical wooden boats over 100m are at the threshold. ... ... Regardless, modern wooden boat manufacture halted for many reasons at around 100m length mark. ... But here we are talking about sailing vessels, yes? Those ships had massive stresses induced by their rigging and wind, which does not apply to the ark, yes?
... Finally, I will accept as evidence that previous attempts and this attempt will require sub-structures on land and/or afloat to make it viable and, it could be argued that modern H&S requirements mean that less risks have to be taken but, that indicates that quantitative risks exist with such a structure. ... Part of the problem I see is envisioning the ark as a ship, when in fact looking at it as a barge is much closer to the need of the vessel: a big box with lots and lots of compartments for storing all the animals. That means bulkheads, some running full length and some athwartship and some horizontal. An integrated design would be a honeycomb structure that could have a lot of strength, as the longitudinal bulkheads replace the keel (and modern barges are designed this way).
At the same time I will accept that because it has not been made, that does not mean it cannot be made. and I sometimes wonder what it would be like to have seasick elephants on board ... Enjoyby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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Percy Member Posts: 22934 From: New Hampshire Joined: Member Rating: 6.8
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RAZD writes: If you assume the cross members are actually just image artifacts that aren't really there, and that the boom is actually an A-frame that isn't in the image, then of course my objections disappear. But you only just now introduced these possibilities, ... See Message 583 ... You said "lighting highlights" and added later, "Note the sunlight to the right and a shadow on the lower end of the boom?" I had no idea you were trying to say that those cross members were image artifacts and were not actually present in the original drawing. But I agree now that the cross members are probably image artifacts. The boom still has problems, as you note later, but not the ones I thought it did, so there's not much point in further discussion.
Sorry, but you made a claim that the boom would be too flimsy and would collapse. All I have asked you to do is make the calculations to show this, which you have resisted doing so far. Curiously I am not convinced by opinion, and without the evidence you have made your case -- you have not provided the evidence to support your claim. You constructed some hoops, demanded I jump through them, then became personal when I instead tried to establish if we were really looking at the same thing. --Percy
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RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
But I agree now that the cross members are probably image artifacts. The boom still has problems, as you note later, but not the ones I thought it did, so there's not much point in further discussion. Agreed. I don't think we can figure out what the artist intended that to be. Enjoy Edited by RAZD, : finishedby our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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ringo Member (Idle past 662 days) Posts: 20940 From: frozen wasteland Joined: |
Percy writes:
You're making far too much of a drawing. It's a drawing.
That boom seems as self-evidently impossible as this Dr. Seuss building
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Percy Member Posts: 22934 From: New Hampshire Joined: Member Rating: 6.8 |
ringo writes: You're making far too much of a drawing. It's a drawing. Yes, I was poking fun at a drawing of Noah's ark under construction by focusing on a lattice boom constructed of wood. I wasn't making very much of the drawing at all except as an object of ridicule, but you and RAZD both insisted that the crane boom could very easily be real. You thought you saw an A-frame that clearly isn't there (we're viewing the boom from below for much of its length and there are clearly no cross members between the two beams nor do they form an "A" - the two beams are not side-by-side, nor do they ever come together to form an "A"), and RAZD demanded calculations. Anyway, you've read forward by now and have discovered that what I thought were innumerable cross members in a wooden lattice boom (the most overtly apparent ones circled in red here):
Were actually image artifacts. But I think both you and RAZD would have to concede that the wooden lattice boom I thought was in that image really *is* impossible. Although somehow I don't think you will. --Percy
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RAZD Member (Idle past 1655 days) Posts: 20714 From: the other end of the sidewalk Joined: |
... But I think both you and RAZD would have to concede that the wooden lattice boom I thought was in that image really *is* impossible. Although somehow I don't think you will. Indeed. I would argue against impossible without demonstration of same. Unlikely I wood agree with. by our ability to understand Rebel☮American☆Zen☯Deist ... to learn ... to think ... to live ... to laugh ... to share. Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click)
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