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Indian startup 3D prints rocket engine in 72 hours

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Re: Indian startup 3D prints rocket engine in 72 hours

#201
post #71

Earlier quoted context omitted.

What part is not true? https://www.youtube.com/watch?v=kz165f1g8-E I'm sure that there are lots of problems with this approach, but it is not as obvious as your comment makes it out to be.

The part which is not true is: "removing the need for postfabrication qualification"

Makes sense, thank you

Re: Indian startup 3D prints rocket engine in 72 hours

#202

> The machine also automatically outputs a report that details any deviations during printing, removing the need for postfabrication qualification. Anyone who's previously worked with 3D printing knows that this simply does not pass any kind of a sniff test. Both preventing and detecting internal defects is one of the, if not the hardest problem in 3D printing. There are many large companies trying to find ways to re…

They may be skipping small portions of the post-print qual. Or more likely, they're just more confident that the pieces being created are of a certain level of quality. It's a hype-y statement but they're probably trying to highlight that they're doing some sort of software-defined quals.

Re: Indian startup 3D prints rocket engine in 72 hours

#203
post #198

Earlier quoted context omitted.

Therac-25 is more like a stuck accelerator pedal. The operator did not command the machine to deliver too much radiation, that happened outside their control.

And you think that a driver commands their Tesla to run into an object when they enable autopilot or FSD?

One is a failure to act as an agent - to control the car and make decisions. Another is a failure to even be a reliable tool - to do what the operator commands. Very different.

Creating Agents is a lot harder.

Re: Indian startup 3D prints rocket engine in 72 hours

#204

Earlier quoted context omitted.

I take it you've seen the DIY 3D printed SAM some random Hong Kong dude made? https://www.youtube.com/watch?v=UvcDwSmmxWs

I really would love to have the time and energy to replicate that. That guys work is pretty nuts

based on his other videos, either he's actually a Chinese missile scientist or you can pretty much make an entire rocket fleet in your farm in modern China

Re: Indian startup 3D prints rocket engine in 72 hours

#205

Earlier quoted context omitted.

>> maybe the juice isn't worth the squeeze In rockets/aerospace, where the failure of any one of a thousand different parts means instant disintegration, checks are always worth the squeeze. Everyone talks about building rockets on the cheap and accepting a slightly-higher failure rate, but in reality that doesn't work. Even a tiny increase in component fault rates translates to total mission failure once multiplied…

this might be 20th-century thinking. if you can build enough copies of a rocket cheap enough, maybe disintegrating a bunch of them isn't a showstopper

Right, because as one of your rocket customers, I'm totally fine with you disintegrating my one-of-a-kind payload

Re: Indian startup 3D prints rocket engine in 72 hours

#206

Earlier quoted context omitted.

> if you can build enough copies of a rocket cheap enough, maybe disintegrating a bunch of them isn't a showstopper The problem with that idea is that you won't be legally allowed to launch again until you root cause and fix the failure, which can take months (or years if you're Blue Origin). Also, your insurance rates tend to go up a lot when your rockets blow up regularly, which tends to push customers away. In pra…

Doesn't work? It seems to be working great for the industry leader.

> Doesn't work? It seems to be working great for the industry leader.

What are you talking about? SpaceX's Falcon 9 is arguably the most reliable rocket ever made. They've launched hundreds of times in a row without failure.

If your point is that they're blowing up Starship prototypes, well... they're in the middle of a development program and they're not flying customer payloads.

Re: Indian startup 3D prints rocket engine in 72 hours

#207

>Constructing a rocket engine using conventional approaches can take months, followed by extensive qualification testing to ensure it meets the required specifications. Using a metal 3D printer from German company EOS, Agnikul produced its engine in roughly three days. Agnikul printed the engine out of inconel, a high-performance alloy of nickel and chromium that can withstand high temperatures and mechanical loads.…

At the very least, 3D printing allows nearly full automation without having to create expensive custom production lines.

Re: Indian startup 3D prints rocket engine in 72 hours

#208
post #38

Earlier quoted context omitted.

you do, if you have sanctuary cities and entire states openly claiming they will not arrest people who break immigration law, it reduces the ability of USA to actually pass policies to take in more skilled immigrants who'll be a net benefit to America as a whole.

Like the War On Drugs, the human cost, violence, and intrusiveness of enforcement is worse than the alleged problem. The much-vaunted localism of America lets states and cities decide that it's not a problem for them to allow people to live there, and they don't want to help the big bad Federal government disrupt that. (it's still no picnic being in that category, unable to register for social security or even take a…

Of course when the federal government decided to let millions of them in and the local government in Texas decided that it was a problem for them and decided to enforce it themselves, all those people who are so much in favor of local control when it comes to "sanctuary cities" suddenly lost their shit.

Re: Indian startup 3D prints rocket engine in 72 hours

#210

Earlier quoted context omitted.

To steelman the argument, maybe they meant "the monitoring system is good enough at catching defects that if none are reported, the engine will probably pass an all-up hotfire test of the engine". Of course you could do a water or air-pressure leak test on the plumbing pretty easily, and you would likely do that on the first 30 engines... But if you have confidence in your build process, maybe the juice isn't worth t…

>> maybe the juice isn't worth the squeeze In rockets/aerospace, where the failure of any one of a thousand different parts means instant disintegration, checks are always worth the squeeze. Everyone talks about building rockets on the cheap and accepting a slightly-higher failure rate, but in reality that doesn't work. Even a tiny increase in component fault rates translates to total mission failure once multiplied…

My dad works in aerospace. In no field or world does anyone actually check every little part.

You create a process, you test that process so that you understand its limits, and then you make sure to follow that process.

Now I don't know if 3D printing rocket parts actually works and I have my doubts but this startup is currently testing the process and they will figure out its limits. That's the whole point of R&D.

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