Comments by "kazedcat" (@kazedcat) on "The Genius of 3D Printed Rockets" video.

Spacex is constructing rockets in open field. The heavy inspection old space is doing is to inflate the cost plus contract. Pressure test and cryo test will reveal manufacturing defect.
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@ChrisSmithy I don't know about Relativity. But Spacex's Superdraco engine is 3d printed. The combustion chamber and nozzle is one 3d printed piece and they are flying those engines to the ISS with astronauts on board. There are a lot of video on the test firing of the Superdraco engine. So the strength of a 3d printed part is not really a question because we have a working example what matters is the design.
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@rockets4kids Spacex is now reliably sending astronauts to the ISS. Boeing could not even get near the ISS. Inspection is subject to the judgement of human inspector. Testing are more objective measure of quality of work either it passes on your test criteria or it does not. That is why more pressure test, cryo test, fire test instead of more inspection. You don't need to inspect every weld when you know the entire thing can withstand a 150% pressure test.
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Solaroid444 They have test fired 3D printed combustion chamber those things need to be very strong to hold together at extreme temperature and pressure not to mention there is cryogenic fluid running on the outside for cooling. Mig welding will not stand up to something like that. As they said proper custom designed material can make 3D printed metal stronger.
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@uhmidk7 No you are blinded by "better than sorry" bias. Pressure testing and Cryo testing should reveal the manufacturing defect better than inspection. Pressure testing is objective measure specially if you add 50% safety margin in the testing. So do 1.5x of maximum pressure then any defect should result into a test failure. Inspection depends a lot on the thoroughness of the human inspector so there is a lot more human factor involve so the result is actually less conclusive than just doing 1.5x pressure test and cryo test. Doing multiple pressure, cryo test and static fires are enough validation and don't need expensive human inspection which should only be needed when things fail during testing.
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They are all infected that is why they work together. If I remember correctly Dark Archon has the mind control ability. I use to play with my goal being to be able to produce all the units of all the race and there is a trick to do that by selecting a specific starting race.
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@rockets4kids Does Falcon 9 reuse qualify for an example. Spacex does not even wash the soot out of the booster.
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@Markle2k It could be argued that a 3d printer is more advance and offer more precision than a robotic welder.
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Markle2k What it looks like does not matter as long as it can throw stuff into orbit.
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