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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

#191

Post by gridspy »

abduhl wrote: post #176
ETH_start wrote: post #153

Earlier quoted context omitted.

Driver control IS making the driver responsible, by definition. Tesla is legally required to put the driver in control. This is a driver assist program. There is no way such a program, that is subordinate to the driver and depends on the driver being in control, can protect the driver from not doing their part, and driving.

First, Tesla is not legally required to put the driver in control - they are free to indemnify the driver completely and shoulder all of the liability themselves. Second, who do you think was ultimately the one at fault for the excessive radiation doses caused by the Therac-25 machines: the machine technician operating the machine or the machine manufacturer? If it isn't the technician then I don't understand your ar…

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.

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

#192

Post by adventured »

fwip wrote: post #174
chasd00 wrote: post #130

Earlier quoted context omitted.

If you don't mind sharing, i'm curious to know where you live. I live in North central Oak Cliff which is a large, predominantly hispanic, area consisting of multiple neighborhood just SSW of downtown Dallas. In my neighborhood there's a local Mercado that i can walk to for small things, i speak enough Spanish to manage but I'm eyed with suspicion from when i go in to when i leave. My wife is a HS teacher with about…

If 20 of the kids spoke Spanish and 2 of the kids spoke English, doesn't it make sense to teach the course in Spanish? Why would the teachers get in trouble?

For now at least half of the US is pretending there aren't 40-50 million illegal immigrants in the US, even though the country is overflowing with undocumented persons and it has become an enormous problem. Every mid-size town and above has a lot of illegal immigrants today, whereas 20 years ago there were few. So if you start switching public school systems over to Spanish because entire schools are now filled with illegal immigrants, or children of illegal immigrants, it's going to get a lot of unwanted attention. Plus it reveals that the US is fracturing rapidly. Whereas English is drastically more valuable than Spanish economically, the US is developing a large population base that does not speak English and it's quite bad for the country's cohesion and economic outcomes.

I'm seeing this firsthand. Where I live in a mid-size university town, 20-30 years ago there was practically zero illegal immigration, undocumented persons. It was fairly unheard of. Now there are a vast number of Spanish-only speaking illegal immigrants. My apartment complex in the span of a few years has become 3/4 illegal immigrants that only speak Spanish, almost entirely young adult males. They harrass anyone that isn't Hispanic and have tried to push all other tenants out of the complex. The police are called frequently for violence issues, and being uneducated young adult males they drink heavily and trash the place constantly.

It can't be fixed either. If you just remove the gigantic base of illegal immigrants GDP will plunge by at least 10%. Nobody will do that. There is no path forward other than chaos. No serious immigration reform will get passed near-term.

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

#193

Post by hi-v-rocknroll »

It sounds like they're not doing QC/QA, which would be unwise and maybe isn't necessarily true.

While 3D printing allows printing shapes that cannot be forged or cast, testing is always needed as part of the manufacturing process feedback loop. X-ray and dye penetration nondestructive testing check for abnormalities on accessible services, but destructive testing is needed sawing samples into slices to also check them for hidden defects.

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

#194

Post by schmidtleonard »

nordsieck wrote: post #158
jes5199 wrote: post #156

Earlier quoted context omitted.

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

> 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.

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

#195

Post by gridspy »

OutOfHere wrote: post #182
constantcrying wrote: post #172

Earlier quoted context omitted.

I sincerely hope you are never involved in any aerospace projects.

Like I said originally, when you run out of arguments, not that you ever had one really, you resort to forms of attacks that are not substantiated by any logic. You don't know me or what I would do if I were or were not involved in aerospace. Maybe you want to go taunt Elon Musk for how many rockets his company has blown up.

> Maybe you want to go taunt Elon Musk for how many rockets his company has blown up.

We know that Elon's SpaceX has many machines inspecting 3D printed (and other) parts, as per the SpaceX factory tours on YouTube. https://youtu.be/xahiWQQKw7Y?si=UGZ1u9xTil5iYoBi&t=71

Also, SpaceX blows up very few (none?) operational rockets. They only tend to blow up in novel ways while testing new technology.

Bear in mind that the SpaceX Raptor is a cutting edge engine - full flow staged combustion is hard.

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

#196

Post by gridspy »

nvy wrote: post #135
1024core wrote: post #103

Earlier quoted context omitted.

Wright Brothers first airplane flew only 100m or so.

The "Wright Brothers" moment for rocketry happened 60 years ago.

The first useful rockets were during the second world war, used for artillery into London. So over 80 years ago. https://en.wikipedia.org/wiki/V-2_rocket

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

#197

Post by OutOfHere »

constantcrying wrote: post #188
OutOfHere wrote: post #182

Earlier quoted context omitted.

Like I said originally, when you run out of arguments, not that you ever had one really, you resort to forms of attacks that are not substantiated by any logic. You don't know me or what I would do if I were or were not involved in aerospace. Maybe you want to go taunt Elon Musk for how many rockets his company has blown up.

If you don't understand that rocket hardware needs QA, please stop talking about the subject. It is like a software engineer who believes that software should be shipped without any testing. >You don't know me or what I would do if I were or were not involved in aerospace True. I still hope that you are never involved in any aerospace or remotely safety critical project.

I hope you are not involved in anything at all, as you look to be a fairly toxic person to be around who will put others down at all costs.

Also, like I said, you have no idea of the emphasis I place on safety when the situation and funding merit it.

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

#198

Post by abduhl »

gridspy wrote: post #191
abduhl wrote: post #176

Earlier quoted context omitted.

First, Tesla is not legally required to put the driver in control - they are free to indemnify the driver completely and shoulder all of the liability themselves. Second, who do you think was ultimately the one at fault for the excessive radiation doses caused by the Therac-25 machines: the machine technician operating the machine or the machine manufacturer? If it isn't the technician then I don't understand your ar…

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?

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

#199

Post by mywittyname »

skybrian wrote: post #132
Etheryte wrote: post #26

> 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…

I’m curious about why that is. Naively, it seems like printing layer by layer would allow for a lot of inspection. Maybe even photograph each layer as you go? And then test and go back to see what kinds of defects were apparent in the photos.

> Maybe even photograph each layer as you go?

Differential cooling is an issue, and is one that isn't apparent until the layers have already been printed.

If their process actually works, whatever they are doing isn't trivial.

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

#200

Post by timerol »

sandworm101 wrote: post #142
NortySpock wrote: post #127

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…

> checks are always worth the squeeze

This is simply inaccurate. You can spend months and hundreds of millions of dollars running scanning electron microscopes over all of your parts - no one does this, because it's not "worth the squeeze". The question is where to draw the line, and I have no idea what your opinion is there.

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