Building a rocket engine from scratch • Hacker News Board

Re: Building a rocket engine from scratch

#81

Post by HeyLaughingBoy » Fri, May 03, 2024, 9:09 PM UTC

quartesixte wrote: post #74

greenish_shores wrote: post #57

Earlier quoted context omitted.

Honestly I did read that as "Employers who are married to their job are the best employers". You probably won't treat them like shit, but they'll still remain married anyway. But such employees will sometimes leave and build their own stuff. Which they'll very likely succeed at, exactly because of the approach they have. Ultimately, I think these are a bit different fields/markets, and a bit different kind of jobs. E…

It's a lot harder to just spin-off and "build your own stuff" in hardware though, which is I think what keeps the "married employees" around longer. The startup costs are much higher and riskier. And you need a lot more people. Building that rocket engine from scratch probably required around 50 - 60 people to really get it all together. Also, a rocket engine is a core feature of a rocket (literally cannot fly withou…

This was one of the main reasons why I didn't have side projects for a very long time. My day job was fun, and it scratched every itch I had. It was such an expensive project that I knew that I simply couldn't afford to do anything that would excite me that much, so I threw all my creative energy into the job.

Eventually though, it became just a job, as it always does. And then the gaze turned elsewhere, looking for more enjoyment and satisfaction.

Re: Building a rocket engine from scratch

#82

Post by HeyLaughingBoy » Fri, May 03, 2024, 9:12 PM UTC

hinkley wrote: post #68

avmich wrote: post #66

Earlier quoted context omitted.

I interpret this as that SpaceX has a high margin between market prices and their internal costs, so they can safely reduce prices when needed while remaining profitable. The competitor of course should aim not to the current prices, but to SpaceX's costs to be able to compete on the market.

I probably over summarized. I think there’s still room to undercut or compete (particularly on specialty projects) until SpaceX hits 10x for sure, and maybe as high as 15x.

And even if there isn't, when SpaceX is booked out for years and you need a launch slot in 6 months, that's when having competition is valuable.

Always look for other ways to compete besides price. (not intended to be as preachy as it sounds :-)

Re: Building a rocket engine from scratch

#83

Post by greedo » Fri, May 03, 2024, 9:12 PM UTC

randmeerkat wrote: post #59

myrmidon wrote: post #54

Earlier quoted context omitted.

I consider the view "many discoveries were made much earlier by soviet counterparts" to be mostly incorrect and heavily biased. But it is a common and easy trap for a lot of nationalities to fall into, because there are innumerable discoveries that happen before (and/or independent of) the canonical "inventor" (and you're automatically more likely to know the independent inventors if they come from your country!). Re…

> the cold truth is that it's mostly a personality cult and that any single scientist that ever existed, no matter how brilliant, was still replaceable I found the MBA.

Nah, it's really akin to the debate historians have over Great People or Inexorable events. Would calculus have been discovered had Liebniz and Newton died in a duel? Would the Panama Canal still have been built had Teddy Roosevelt not been its primary proponent? The Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head.

Re: Building a rocket engine from scratch

#84

Post by HeyLaughingBoy » Fri, May 03, 2024, 9:18 PM UTC

spxneo wrote: post #8

AndriyKunitsyn wrote: post #4

Nice read. The fact that it is possible to 3d print metal parts that withstand temperatures and pressures of a rocket engine is so exciting. How expensive is it?

side question to this: where can i design stuff involving metal parts (presumably in CAD tools) and have it printed en masse? With PCBs? ex) car components

3D printing is very popular right now. And for good reason. However, it often masks the fact that there are many ways to manufacture most products, and often, 3D printing is the most expensive one.

Meaning that instead of thinking "how do I 3D print this?" you should be thinking "how do I manufacture this?"

Something as simple as making a drawing, specifying the material and quantity needed and then going on reddit/r/manufacturing and asking "how would I build 50 of these" can provide very useful answers, even if you have to do a bit of research later to understand what you've been told.

Re: Building a rocket engine from scratch

#85

Post by LM358 » Fri, May 03, 2024, 9:24 PM UTC

sr-latch wrote: post #44

buescher wrote: post #24

NASA's report server is a national treasure, especially the material from the 50s and 60s that he references. Some of the most crisp and succinct technical writing you'll find, and you can infer a lot about how they ran projects. Declassified NRO reports are also very good - you can see the Lockheed Skunk Works principles in action. Example: https://www.nro.gov/Portals/135/documents/foia/declass/WS117...

and if you're ever writing 1DoF codes yourself, NASA's CEA for propellant chemistry calculations is freely available https://cearun.grc.nasa.gov/

The executables and source code are sadly not freely available any more, allegedly for ITAR reasons.

Re: Building a rocket engine from scratch

#86

Post by randmeerkat » Fri, May 03, 2024, 11:51 PM UTC

greedo wrote: post #83

randmeerkat wrote: post #59

Earlier quoted context omitted.

> the cold truth is that it's mostly a personality cult and that any single scientist that ever existed, no matter how brilliant, was still replaceable I found the MBA.

Nah, it's really akin to the debate historians have over Great People or Inexorable events. Would calculus have been discovered had Liebniz and Newton died in a duel? Would the Panama Canal still have been built had Teddy Roosevelt not been its primary proponent? The Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head.

> Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head.

If Sergei Korolev didn’t die suddenly and unexpectedly, the Soviets may have actually won the race to the moon. Their space program atrophied afterwards and struggled to succeed.

I really wonder at the modern obsession with associating people with cattle.

Re: Building a rocket engine from scratch

#87

Post by greedo » Sat, May 04, 2024, 2:45 AM UTC

randmeerkat wrote: post #86

greedo wrote: post #83

Earlier quoted context omitted.

Nah, it's really akin to the debate historians have over Great People or Inexorable events. Would calculus have been discovered had Liebniz and Newton died in a duel? Would the Panama Canal still have been built had Teddy Roosevelt not been its primary proponent? The Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head.

> Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head. If Sergei Korolev didn’t die suddenly and unexpectedly, the Soviets may have actually won the race to the moon. Their space program atrophied afterwards and struggled to succeed. I really wonder at the modern obsession with associating people with cattle.

Cattle?

Re: Building a rocket engine from scratch

#88

Post by quartesixte » Sat, May 04, 2024, 4:19 AM UTC

quartesixte wrote: post #76

criddell wrote: post #58

> You might call me an unlikely candidate to lead an engine program from scratch, but I was hired by ABL in 2018 to do just that. My background was in commercial aircraft interiors, web development, semiconductor fab fluid components, and SpaceX Falcon 9 hydraulic systems. I don't mean this as an insult, but why did they hire you? It's obvious now that you were a great choice, but from your background story I wouldn'…

Seems like from the blogpost that the writer and the founder were part of the same cohort at SpaceX. I would hazard a guess that they became friends, and had planned to do this together, and he joined ("hired") as soon as feasible for him (or the founder gained enough traction to pull him away from SpaceX).

Oh and as an additional comment: Propulsion Engineers are a niche, specialized branch of mechanical engineers. They are the ones who usually design engines.

The writer probably was referring to the fact that he was just a regular mechanical engineer and not a Propulsion Engineer.

Re: Building a rocket engine from scratch

#89

Post by gregw2 » Sat, May 04, 2024, 7:48 PM UTC

greedo wrote: post #87

randmeerkat wrote: post #86

Earlier quoted context omitted.

> Apollo project shows that Big Events can still happen even when it's most eloquent proponent gets a bullet to the head. If Sergei Korolev didn’t die suddenly and unexpectedly, the Soviets may have actually won the race to the moon. Their space program atrophied afterwards and struggled to succeed. I really wonder at the modern obsession with associating people with cattle.

Cattle?

I’m guessing this is a techie reference.

Computer servers can be divided into two roles in modern technical architectures… they are either “cattle” or “pets”. Pets are computer servers that have names and are always up. Cattle are servers that are transient, spun up and down as needed and do not necessarily have any long running identity/name as a component of a larger system.

http://cloudscaling.com/blog/cloud-computing/the-history-of-...

The poster is making a critiques of how by treating historical persons contributors as cattle, we are considering them a dispensable, unnamed, a commodity that is easily replaced and interchangeable and missing their very real contribution, value, and humanity.

Re: Building a rocket engine from scratch

#90

Post by greedo » Sat, May 04, 2024, 9:49 PM UTC

gregw2 wrote: post #89

greedo wrote: post #87

Earlier quoted context omitted.

Cattle?

I’m guessing this is a techie reference. Computer servers can be divided into two roles in modern technical architectures… they are either “cattle” or “pets”. Pets are computer servers that have names and are always up. Cattle are servers that are transient, spun up and down as needed and do not necessarily have any long running identity/name as a component of a larger system. http://cloudscaling.com/blog/cloud-compu…

I thought also that he was making the docker/container reference, just didn't see how it applied. Thanks for your expansion.

I do find the Great Person theory and its critiques fascinating. I think of how Kennedy navigated the Cuban Missile Crisis and avoided nuclear war, then I think of how the sheer consensus of the US military after WW2 was to build a huge nuclear arsenal and use it any possible chance.