The website is a user-friendly proxy for youtube - if it has trouble loading the video, there's a link to the youtube page (or just edit the url).
You may have read things like Why Amazon Can't Make A Kindle In the USA, but what about a hand tool with no electronics, just a few materials, large tolerances, and a simple assembly process? The same problem of manufacturing engineering being exported for greater integration with manufacturing labor applies to that, too - according to this, American "tool and die" capabilities for small-scale manufacturing are gutted. (I suspect the this video overstates the problem, because the biggest obstacle came when the non-manufacturing engineer with a small budget wanted to contract out a specific need - molds for plastic injection molding, which the molder would have sourced from the PRC - and two other engineers lent their expertise for two different ways of manufacturing plastic injection molds, and he found a mold-maker, after he needed to change the material of a part, but it's still a big deal that there aren't more American vendors advertising these capabilities.) And the video didn't even touch the materials supply chain...
(The completed grill scrubber was priced at $75 and the initial batch sold out within hours, in case you were wondering.)
If you haven't read things like that Forbes series, you might not fully appreciate that it's very easy to have a false perception of what the manufacturing capabilities of other countries are, due to selection bias in exports; there's often a wide variety in the quality of goods produced in a given country and only a narrow range of quality that's economical for you to import. One famous example is the brand images of German cars in America, which only imports expensive German cars. Less famously, there's been a secular trend of American imports of Japanese musical instruments going from the bottom to the top of the Japanese (followed by other Asian countries') production ranges and many American musicians assume each decade's imports were a representative sample. But, since manufacturing labels reflect final assembly, increasingly complicated supply chains are mostly invisible to the consumer. It'd be interesting to know what this partnership would have done differently, if they had expanded their searches to Mexican and Canadian suppliers as an acceptable alternative to American suppliers (as a larger-scale business intent on "friend/near-shoring" would), but the value of purism vs general applicability is a "six of one, half a dozen of the other" type thing.
As someone who's pro-industrial policy and also anti-CCP, I think think the supply chain problem is one of those issues with a lot of misplaced attention, wherein globalization gets projected onto various political narratives, to the detriment of analyzing capability.
(Hopefully that's enough of a conversation-starter, without crossing into CW!)
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Notes -
Thanks for the link. Given that the ships in that graph were rather small, I tried to calculate the force per ton for a TI-class supertanker. To my surprise, it turns out that the number I get out (F/m=P/v/m=37MW/(30.6km/h * 441kT)=10N/T) is rather similar to the barge.
From physics, I would have assumed that the friction of a ship has roughly two components, one which is proportional to the cross-section of the underwater parts of the hull (and to the velocity squared) and one which is proportional to the area of the underwater hull (and to the velocity). Notably, both of these are decidedly sublinear to the displaced water volume, so going from a 1kT barge to a 441kT supertanker should really lower friction.
Now, it could be that the 37MW are the absolute maximum rating of the engine, and that in normal operations it used only a fraction of that power at top speed, or that the conversion of the engine power into a forward force is inefficient for some reason, but I do not have a great explanation.
I notice I am confused.
The other curious thing about that table is that once your railroad track has an incline, the story becomes much different. For example, with an incline of 1%, you will tithe 100N/T to gravity, regardless of your velocity.
But we can also invert that. An incline of 0.1% (one meter per kilometer) imposes a force of 10N/T from gravity. Per the plot, a 60ton railroad car on such an incline (which would not even be noticeable to the naked eye) would (once we push it a bit to overcome static friction) accelerate until it reaches a velocity of 150km/h. Now, if you try to tell me that 40 foot container filled with water falling door forward out of a plane would reach a terminal velocity of 150km/h, I would already find that unlikely.
I would like to roll a will save to disbelieve, please.
Don't container ships usually travel much, much faster than barges?
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I think I read somewhere that surface ships actually experience drag proportional to the cube of speed, due to the bow wave.
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The physics of shipbuilding is incredibly counterintuitive. This is because we have bad intuition about the physics of fluids in general, and the physics at the intersection of the fluids air/water compounds this.
One super counter-intuitive concept is the Froude number, which is a dimensionless quantity that determines (roughly speaking) how fast a ship can go at max efficiency, but doesn't depend on any of the quantities you mention. The formula is:
Fr = V/√(g×L)
Where:
There are dozens of other constants like this that ship designers measure/use, and none of them are intuitive.
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