Raptor 4 is not LEET

[Sarigolepas]

According to Musk raptor 4 has increased TWR and reduced costs compared to raptor 3:
https://x.com/elonmusk/status/1985187793556111427
They are probably not achieving higher TWR by increasing thrust, otherwise he would have said that. They are just reducing mass.
So my guess is that the new production process used to reduce costs also allows cladding (layers of different alloys) with high strength alloys on the outside and high temp alloys on the inside.

The process can be cold:

Warm

Or hot


But basically they would make a weak but lightweight engine and then add a layer of stainless steel around it for strength.

[Sarigolepas]

For LEET Musk said himself that there will be a different engine not named raptor:
https://x.com/elonmusk/status/1460813037670219778
A new name means a new combustion cycle so LEET will probably use active cooling of the turbine blades and might even allow them to remove the preburners. Which is why raptor 4 is not LEET IMO.

[steveleach]

For LEET Musk said himself that there will be a different engine not named raptor:
https://x.com/elonmusk/status/1460813037670219778
A new name means a new combustion cycle so LEET will probably use active cooling of the turbine blades and might even allow them to remove the preburners. Which is why raptor 4 is not LEET IMO.

When was the last time Elon (or anyone at SpaceX) mentioned LEET anyway?

That quote was from 2021 when Raptor 2 wasn't heading in the right direction, and before Elon took charge personally, resulting in Raptor 3, which he seemed very proud of.

L33T was likely just a threat aimed at the Raptor team's leadership.

[Sarigolepas]

For LEET Musk said himself that there will be a different engine not named raptor:
https://x.com/elonmusk/status/1460813037670219778
A new name means a new combustion cycle so LEET will probably use active cooling of the turbine blades and might even allow them to remove the preburners. Which is why raptor 4 is not LEET IMO.

When was the last time Elon (or anyone at SpaceX) mentioned LEET anyway?

That quote was from 2021 when Raptor 2 wasn't heading in the right direction, and before Elon took charge personally, resulting in Raptor 3, which he seemed very proud of.

L33T was likely just a threat aimed at the Raptor team's leadership.

Possible.
But when asked about turbine blade cooling last year he said "We had that discussion many times"

So there are still ideas that are too big for raptor and would be a whole new engine.

Besides, the main upgrade with raptor 4 is cost so it's mostly a change in the manufacturing process. Using powder bed technology for the high temp part of the engine with smaller cooling channels and then adding layers of high strength alloys around it using directed energy deposition would both cut costs and reduce mass.

[wannamoonbase]

Reading between the lines it sounds like they are comfortable with Raptor 3, not done, but have a pretty good idea of what they have and what they can reliably achieve.

And it maybe that they have a small group working on Raptor 4, or at least have that list of Raptor 4 things they want to achieve.

The man is many things, relentless, is certainly one of them.

[Sarigolepas]

Reading between the lines it sounds like they are comfortable with Raptor 3, not done, but have a pretty good idea of what they have and what they can reliably achieve.

And it maybe that they have a small group working on Raptor 4, or at least have that list of Raptor 4 things they want to achieve.

The man is many things, relentless, is certainly one of them.

I think Musk is quite satisfied with the thrust on raptor 3 since he has not mentioned a raptor-boost with a bigger throat for quite some time.
However he is probably quite mad at the cost of reusability, which cuts the payload in half. So the goal right now is to cut dry mass as much as possible. He is also mad at the manufacturing cost.
I don't think there will be any change in the combustion cycle, preburner temperature and chamber pressure for raptor 4. They will just use a different manufacturing process to cut cost and hopefully take advantage of it to use different alloys for different parts of the engine and only use superalloys where necessary, which should allow them to use higher strength alloys and cut mass.

[Twark_Main]

They are just reducing mass.
So my guess is that the new production process used to reduce costs also allows cladding (layers of different alloys) with high strength alloys on the outside and high temp alloys on the inside.

...

But basically they would make a weak but lightweight engine and then add a layer of stainless steel around it for strength.

This is already what SpaceX does for Raptor. The inner material is a copper alloy for maximum heat transfer, and the outer layer is a high-strength steel alloy.

[Sarigolepas]

They are just reducing mass.
So my guess is that the new production process used to reduce costs also allows cladding (layers of different alloys) with high strength alloys on the outside and high temp alloys on the inside.

...

But basically they would make a weak but lightweight engine and then add a layer of stainless steel around it for strength.

This is already what SpaceX does for Raptor. The inner material is a copper alloy for maximum heat transfer, and the outer layer is a high-strength steel alloy.

Interesting.
There are some 3d printed materials with over 3,000 MPa of tensile strength:
https://vbncomponents.com/materials/
That would be a great outer layer to handle the pressure.