Comments by "JJ" (@jj4791) on "OceanGate Titan Hull - Hundreds of Ill-advised Carbon Fiber Grind Spots" video.

😂😂😂 the strength of the material is almost entirely in the fibers. Perhaps nobody told them that misalignment of the fibers results in essentially zero strength. Then cutting said fibers, by grinding off the fiber misalignment that caused this waviness, is unbelievably ill-advised. A savvy consumer wouldn't even swing a golf club made with this poor of workmanship. And there is somebody on this planet somewhere who physically took an angle grinder to a pressure hull, which ended up ending several human lives due to this clear and obvious mistake. They deserve the guilt they feel. (But probably don't, because they are either dumb order takers, or diagnosable psychos to be working there).
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It is bad on so many levels. Where to start?
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😂😂😂 the strength of the material is almost entirely in the fibers. Perhaps nobody told them that misalignment of the fibers results in essentially zero strength. Then cutting said fibers, by grinding off the fiber misalignment that caused this waviness, is unbelievably ill-advised. A savvy consumer wouldn't even swing a golf club made with this poor of workmanship. And there is somebody on this planet somewhere who physically took an angle grinder to a pressure hull, which ended up ending several human lives due to this clear and obvious mistake. They deserve the guilt they feel. (But probably don't, because they are either dumb order takers, or diagnosable psychos to be working there).
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In theory, you are right. But this is true of fiberglass because the fibers stretch 4.5% and the epoxy resin typically fails at a strain of 1.6% up to 3% for toughened resins. But carbon fiber fails at around 1.2% strain in tension and 0.7-1% in compression. Well below the resin failure strain. Part of the reason carbon fiber composites are so strong, is the fibers reach their limit strength and fail before most the resin that binds them. Where fiberglass composites fail the matrix long before the fibers reach book strength. So fiberglass will always be limited at perhaps 1/3 of book values. And its book numbers are only 1/3 of carbon fiber. So it is pretty low performance, comparatively. S2-Glass pultrusions do perform well as they solve some of these problems. Boron/carbon fiber hybrid is the appropriate reinforcement for OceanGate type uses. Lacking boron is a clear indication these people left a lot of performance on the table. Grinding carbon composite pressure vessels is an indication they were irrational and delusional.
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Whatever the pressure vessel weighs it has to have buoyancy to raise it again. Titanium is strong enough, and much lighter than steel. There is a reason the SR-71 can scoot along for up to 3,500miles between tankers, and the Mig-25 cannot. Carbon is far lighter than either and also nearly as strong. The design choice to go with carbon was both cost of manufacture but also cost of support. A heavy many tons diving vessel takes a many more tons ship. As the diving sub makes a fraction of the total. The total becomes about 3x larger for a 3x heavier diving vessel. Adding costs. Costs that must be paid by a limited number of paying customers. Adding 3x the cost is not good for business when it still costs $200,000 per ticket.
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Differing coefficients of thermal expansion is the first clue.
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The observation that capitalism allowed this is so obvious: Duh. Paying customers who are saving and spending their own earned money on an action of their own choice to go see the Titanic is the driving factor in this and almost any other interaction between otherwise unrelated people. Capitalism is the default market system where any two rational beings exist. Any other system requires force, violence, and murder to make people behave in an irrational manner against their own desires, dreams, goals, or better judgements. Socialism is incapable of creating anything new or useful. This has been proven time and again. There are millions of refugees fleeing Venezuela at this very moment due to enacting unilateral socialist policy. And they are something like the 42nd nation to do a in history. And they are also the 42nd to suffer mass starvation and mass emigration of refugees.
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@ian_b ^ this. NPD is a serious debilitating condition that prevents seeing any flaws in one's clearly irrational ideas. And 99/100 people think these Narcissists are leaders, geniuses, movers and shakers. They are not. They can only cause losses to others as their default.
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@SF-jr1rt in order of bad decisions: Dissimilar materials with different coefficients if thermal expansion for pressure cylinder end-caps. Selecting carbon fiber/titanium that would require an adhesive interface. Carbon fiber lacking Boron fibers in a primarily compression-only high performance application. Grinding said pressure vessels carbon composite layers with belt sanders. Selling tickets to ride on it. And going yourself.
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@peted5217 Will Rogers.
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DEHRP...😂
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Reason is the only absolute. ~ Ayn Rand.
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