Elon się rozpisał na twitterze pod filmikiem pokazującym budowę 3 kopuły:
https://twitter.com/elonmusk/status/1211531714633314304Q:Really curious as to what you think of the explosive hydro forming process that was used for the Saturn V bulkheads.
A:We use that process for the Raptor nozzle jacket. The knuckles of this dome are stamped in Michigan with a 4000 ton car body press, which costs much less for same outcome.
Q:Is there any substantial difference in welding / manufacturing techniques between these bulk heads and and MK-1 / MK-2? Also, LOL 😂
A:Almost everything is different. These parts are stamped vs manually bump-formed & TIP TIG welded vs flux core. Higher precision, stronger joints & 20% mass reduction.
Best would probably be an autogenous laser weld, but we need more precise parts & fixtures. Hopefully get that done in 2020.
Q:Will SpaceX keep manufacturing Starship (and, presumably, Super Heavy too) out in the open, or do you foresee eventually moving production into (the industry norm) cleanrooms?
A:Moving to an enclosed (fairly) clean room environment for SN2 in Jan, although, unlike aluminum, stainless steel welding is not super sensitive. Our main issue here in Boca is that it can get very windy, which affects weld arc & steel melt pool.
Q:Texas, Florida, ... do you have the next starship sites picked out?
A:We’re focusing on Boca right now for Starship & Cape is focused on Falcon/Dragon
Q:It’d be so cool if Tesla motors were powerful enough to spin start! Have you moved onto direct drive / electromechanical on the body flaps with motors yet or still spinning a pump for SN1?
A:Direct drive using several Tesla Plaid motors in parallel for SN1. Simpler, lighter & more fault tolerant. Rear flaps each need ~1.5 megawatts. It’s like moving the entire wing of an aircraft!
Q:Speaking of autogenous, when will we see autogenous pressurization on Starship? I assume the first couple will still utilize helium COPVs like StarHopper?
A:No, will be autogenous from the start, tapping hot CH4 & O2 from Raptor
Q:Have you heard of solid-state ultrasonic welding?
A:Tesla uses that to wirebond cells to module current collectors. Is there a commercially available machine that can weld ~4mm full hard 301 stainless barrels & domes?