I think he said in the press conference that they weren't planning to reuse the core or boosters. (But then mentioned later they wanted some of the parts? IDK)
Correct, the engines were going to be retired anyway but they are keen to reuse the titanium grid fins on the boosters which cost a small fortune to make.
The core actually had older ablative grid fins made of aluminium so no great loss there[0].
Platinum is USD$32K per KG, so if the platinum grid fins are 100KG, then they would cost > $300K each just for materials. With 4 per booster that might be a million dollar price tag for the grid fins.
That would be $3200k for each, but they are made out of titanium, not platinum, and most of the cost is in the work, not material. I'd like to know the price too though.
Titanium isn't particularly terrible to machine. Nothing is hard to machine if your budget can cover the correct tools and you machines can provide the right setting to run those tools.
Your typical mechanical engineer fresh out of school has incredibly limited experience when it comes to things that are not stupid-proof to work with (engineering programs have other priorities). They then go on to build specialized knowledge in various subjects and usually more on the design side, not the execution side. Of course someone who designs plastic molds or simulated impeller designs all day is going to create a black box around things that aren't their specialty. You don't care about how the impeller or mold is made other than knowing that it can be made, what its material properties are and knowing that actually making it involves a bunch of details you don't know so you offload it to a 3rd parts (for the same reasons someone else is having you design the impeller or the mold).
A bunch of engineers and otherwise smart people on the internet saying that titanium is like computer programmers saying residential electrical is complicated or web devs complaining about bash. It really doesn't mean much but people who have no experience with this things tend to think the people who only have a shred know what they're talking about.
It's not difficult. Most other people just know they don't know how to do it and that they don't know what they'd need to know to go about learning how.
It's not that difficult. The more common alloys machine relatively easily; some of the tougher ones can be a pain but not much more than other special purpose materials like Inconel.
ahh, I noticed that in the feed and was wondering why. I guess they expected it was the least likely to work? or needed the better grid fins less because of the cylindrical top
If I understood properly none of the boosters were block 5 so they weren't looking at re-flying them.
They are however interested in recovering the grid fins on the side boosters, which were redesigned to accommodate for the nose cones now sitting on top of them.
The latest hardware revision that's expected to be the mainstay for F9 flights going forward. Has better performance and addresses some reusability issues discovered in earlier blocks.
As far as I know, the center core was a block five one, but they didn't intend to refly it anyway, from what Elon said in the press conference. Maybe they intended to study it? If that's the case, there will probably be another "expandable" block five flight.
The plain is to lock down block 5's design so it can be man rated which in itself would make it more reliable. This will probably not happen until they fly them a few times though so that wouldn't mean the first block 5s would be more reliable.
To be perhaps slightly more accurate, it's like a major version 5.
Almost (if not) all missions include changes of some kind; the manufacturing blocks each have significant, incompatible differences in parts.
Upgrading the grid fins would be a minor version change, modifying the engine to increase its throttle depth a major one. I don't know, but it seems like there would need to be significant re-tooling for each new block, and many parts would be incompatible with previous blocks.
Even if they're not reusing any of it (this time), it's still very useful to examine and analyze how well it's held up.
Perhaps some piece of metal is showing more fatigue than they'd like to see, or a wire had damage to the insulation from a vibration. I'm sure that's the sort of thing they'll be looking at.
The core actually had older ablative grid fins made of aluminium so no great loss there[0].
[0]https://i.redd.it/l6s2bds7pl801.png