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Indian startup 3D prints rocket engine in 72 hours

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111–120 of 288 posts

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

#111
post #59

Earlier quoted context omitted.

I'm not sure how many people know about their 'sound detection system'. Carbon fiber is a fickle beast and is prone to such failures so that alone worried me, but it was incredible for me to learn that they expected some sort of early warning from cracking.

Do you have a link? Google just gives results about the US Navy detection of the implosion…

https://www.wired.com/story/titan-submersible-disaster-insid...

Recent one-year-lookback story by Wired.

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

#112

Earlier quoted context omitted.

"When you don't have any real criticism, just make stuff up! Keep people down at all costs." P.S. Nick checks out.

How is gross negligence on QA not a "real criticism"?

You hardly enough know anything about the project to make an assumption about the absence of QA. If you were an employee there, and you had specific concerns, that would be worth something. You made it up because you had no real point.

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

#113
post #87

>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.…

> Besides, the question I have is why 3D printing? Rocket nozzles are heat limited. You could get more trust out of them only if the nozzle would not melt. So you do a lot of tricks to cool it. One of those many tricks is that you circulate your rocket fuel as a coolant in the wall of the nozzle. This requires an intricate web of many tiny pipes which form the wall of the nozzle. Typically these are constructed by ha…

My guess is failing to read between the lines and taking marketing too seriously.

"Removing the need for postfabrication qualification" doesn't mean "perfectly detects errors" it means "detects errors within our business specs and we expect it to be profitable within that margin".

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

#114
post #73

Earlier quoted context omitted.

If it would be a Tesla, just enough time for the auto-pilot to disengage and claim it was the fault of the user.

Tesla autopilot is not supposed to be unmonitored, so any accidents under its control are entirely the fault of the driver. If a driver disengaged 0.1s before impact, they were derelict in their driving.

OSHA has a nice pamphlet regarding hazard identification and hazard controls. The least effective method of protecting workers is to put the risk on the worker to protect themselves. Your view has a similar vibe to "well they weren't wearing their hard hat and so it's their fault," a view that has been rejected across the board for safety in favor of the view that even letting the situation get to that point is a failure.

https://www.osha.gov/sites/default/files/Hierarchy_of_Contro...

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

#115
post #73

Earlier quoted context omitted.

If it would be a Tesla, just enough time for the auto-pilot to disengage and claim it was the fault of the user.

Tesla autopilot is not supposed to be unmonitored, so any accidents under its control are entirely the fault of the driver. If a driver disengaged 0.1s before impact, they were derelict in their driving.

[flagged]

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

#116

Earlier quoted context omitted.

I wouldn't defend america's immigration system (in my opinion the world should be borderless and you should be able to vote in any location where you can demonstrate that you've performed work for a wage or something like that), but if anyone should be allowed to seek labor by moving freely, it is the unskilled, who are already tremendously disadvantaged by globalization. Skilled labor is unlikely to be tremendously…

Those lines are not imaginary per se. It means that the people living within those imaginary lines have come together with similar ideals and unity, arrived by many years of co-operation, to bestow certain rights and privileges to their fellow neighbors. Those rights were paid in blood, sweat and tears. The reason people organized as tribes matters. Its part of our very nature. And those tribes also respected imagina…

Hardly. The lines are basically drawn by aristocrats of one kind or another and the rest of us have to deal with it. They are expressions of power and very little else, and mostly not the power of the people. The rights paid for in blood, sweat, and tears, as you say, were wrenched from the hands of the kinds of people who draw borders and consist entirely of statements that are borderless assertions of the value of human beings, not citizens. You may be right that there is some kind of fundamental tribal mentality in human beings, but that doesn't mean that enshrining that reality in law or even nurturing it is morally right. The idea that borders benefit the common person better than, for example, a system which genuinely respected the dignity and right of human beings regardless of their geographical coincidences, is bullshit.

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

#117

Earlier quoted context omitted.

How is gross negligence on QA not a "real criticism"?

You hardly enough know anything about the project to make an assumption about the absence of QA. If you were an employee there, and you had specific concerns, that would be worth something. You made it up because you had no real point.

>You hardly enough know anything about the project to make an assumption about the absence of QA.

I take their claims at face value. Either they are for some weird reason lying about not doing QA or they are extremely negligent in their manufacturing. Granted, I can not exclude the first option, but to be honest that might make the company look even worse.

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

#118

Earlier quoted context omitted.

I'm not sure how many people know about their 'sound detection system'. Carbon fiber is a fickle beast and is prone to such failures so that alone worried me, but it was incredible for me to learn that they expected some sort of early warning from cracking.

Well there were probably some early warning signs The problem is that warning sign comes at around 10ms or less before the actual disaster

There were plenty of early warning signs. In a previous dive back in 2019 they had professional submersible designer Karl Stanley on board, who later wrote an email to OceanGate about the worrying cracking sounds he heard.

> "What we heard, in my opinion ... sounded like a flaw/defect in one area being acted on by the tremendous pressures and being crushed/damaged," Stanley wrote in the email, a copy of which has been obtained by CNN.

> "From the intensity of the sounds, the fact that they never totally stopped at depth, and the fact that there were sounds at about 300 feet that indicated a relaxing of stored energy /would indicate that there is an area of the hull that is breaking down/ getting spongy,"

It's more impressive that the sub continued to work while giving warning signs for 4 years.

https://abc7.com/titan-submersible-2023-incident-titanic-oce...

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

#119

I hope this doesn't lead to an exponential increase in space debris.

[dead]

If SpaceX could produce a rocket every 72 hours it would be a concern too.

Also, best of luck in your quest of fighting imaginary villians.

By conflating unrelated things and jumping to conclusions such as that you are not acting as a good ambassador for your country.

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

#120

I hope this doesn't lead to an exponential increase in space debris.

[dead]

I don’t hear anyone disparaging the ability of Indian companies to build great rockets. ISRO has done some really great work, and deserves lots of credit. But this startup seems to be bragging about making some pretty basic mistakes, like claiming not to need QA without having actually done anything to solve that problem (they didn’t build the 3d printer). So they seem to be doing the same kind of non-serious stuff we see from other vc backed startups all over the world which deserves skepticism.
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