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> "This will be the first time that a printed rocket engine sees flight." Is printing engines a tactic for making return flights from Mars more plausible?

krasin 12y ago
These engines are built from Inconel [1] superalloy, which is very hard for machining. 3d printing allows to cut the costs, and also enables more intricate shapes, thus improving the engine efficiency. 1. http://en.wikipedia.org/wiki/Inconel http://en.wikipedia.org/wiki/Inconel
- nickff 12y ago
  The space shuttle's engines are made up of a series of thin inconel sheets sandwiched together, to avoid the problems with machining metals. The most significant machining issue is drill 'walk', which is not specific to inconel, and causes non-straight holes on the plate, which could cause uneven mixture of fuel and oxidizer, thus creating dangerous 'hot-spots'.
cdash 12y ago
If by cheaper then yes and if by printing on mars then probably not.
Crito 12y ago
No. Not with those particular engines anyway. The idea is to make methane/LOX on Mars, but those engines burn MMH/N2O4.
- avmich 12y ago
  Which is really pity, but you can't expect too much. Watching the presentation, I felt that Elon wants to make an impression of XXI-century spacecraft - but he doesn't want to get into shoes of Doug Engelbart making a thing so great nobody will pay him to fully use that. No, Elon firmly wants not the perfect, but profitable solution. Which is very understandable. There are multiple places where SpaceX could really try to do better. The problem is, they'd spend much more money and time and get much less predictable results. Considering they already pushing envelope pretty hard, it's likely a wise decision to also use some more proven technologies.
swalsh 12y ago
Not an expert, but I think 3D printing also gives some possibilities for designs that aren't possible with traditional methods.
- loganu 12y ago
  You're right. Because of the layering of 3D printing, you can create shapes and features that wouldn't be possible with casting, molding, or even 5-axis milling machines. Complex undercuts, empty compartments/ hollow areas to cut weight down, and features similar to extrusion-based design can all be performed in conjunction in a single solid body.

krasin 12y ago

These engines are built from Inconel [1] superalloy, which is very hard for machining. 3d printing allows to cut the costs, and also enables more intricate shapes, thus improving the engine efficiency. 1. http://en.wikipedia.org/wiki/Inconel http://en.wikipedia.org/wiki/Inconel

nickff 12y ago
The space shuttle's engines are made up of a series of thin inconel sheets sandwiched together, to avoid the problems with machining metals. The most significant machining issue is drill 'walk', which is not specific to inconel, and causes non-straight holes on the plate, which could cause uneven mixture of fuel and oxidizer, thus creating dangerous 'hot-spots'.

cdash 12y ago

If by cheaper then yes and if by printing on mars then probably not.

Crito 12y ago

No. Not with those particular engines anyway. The idea is to make methane/LOX on Mars, but those engines burn MMH/N2O4.

avmich 12y ago
Which is really pity, but you can't expect too much. Watching the presentation, I felt that Elon wants to make an impression of XXI-century spacecraft - but he doesn't want to get into shoes of Doug Engelbart making a thing so great nobody will pay him to fully use that. No, Elon firmly wants not the perfect, but profitable solution. Which is very understandable. There are multiple places where SpaceX could really try to do better. The problem is, they'd spend much more money and time and get much less predictable results. Considering they already pushing envelope pretty hard, it's likely a wise decision to also use some more proven technologies.

swalsh 12y ago

Not an expert, but I think 3D printing also gives some possibilities for designs that aren't possible with traditional methods.

loganu 12y ago
You're right. Because of the layering of 3D printing, you can create shapes and features that wouldn't be possible with casting, molding, or even 5-axis milling machines. Complex undercuts, empty compartments/ hollow areas to cut weight down, and features similar to extrusion-based design can all be performed in conjunction in a single solid body.