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Comment by m4rtink | Hacker News Reader

Still, I don't think anyone is ever going to hand assemble thousands of tubes for nozzle cooling & prepare them for brazing.

Not when you can get the same for a fraction of the cost by CNC milling the channels & then shrinking a jacket over it. Or in some cases even 3D printing the thing.

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The assembly of the tube bundle in a nuclear steam generator is still carried out mainly by hand, using hundreds of shims, anti-vibration bars and supports.

At the other end of the spectrum are stamped-plate heat exchangers, which are mass-produced using a press line.

Each has its own specific application, and they are neither comparable nor interchangeable. The comparison makes no sense.

How does SpaceX's 3D printed raptor engine factor into your analysis?

The one that keeps failing?

Does it? SpaceX doesn't publish official numbers, but nextspaceflight.com has the Falcon 9 at 99.5% success rate, which seems a bit better than "keeps failing" to me.

https://nextspaceflight.com/rockets/3/

I actually agree with your point overall, but Falcon 9 uses the Merlin, not the newer raptor 3 for starship which is more 3d printing and has had some teething issues (no definite causation, and I expect they’ll get it sorted).

Falcon 9's don't fly raptors

The Raptor v3 had a 7% (3/39) failure rate on yesterday's Starship Flight 14. As others have mentioned, Falcon 9 uses the Merlin engine, which is a completely different, much lower complexity engine.

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