Sunday, August 22, 2021

Relativity Space and A Worthwhile Video

I've talked about Relativity Space and their concept of 3D printing virtually everything in their rockets - including the rocket itself - several times, most recently in June.  They're continuing work toward the first flight of their Terran 1 rocket later this year.  That linked piece emphasized their plans to develop a large rocket to compete directly with SpaceX's Falcon  9, to be called the Terran R where the R is for reusable.  

Tonight's emphasis is to direct you to a worthwhile 20 minute long video on the YouTube channel Veritasium.  It's 10 days old, but I finally got around to watching it and would recommend it to any space nerds or techno-geeks.  It certainly went faster for me than 20 minutes of most TV programs.  Veritasium's lead, Dr. Derek Muller, conducts a walk around interview with Relativity CEO Tim Ellis.  They carry UV protective masks to watch large metal prints being made, watch the bell nozzle of a rocket engine being printed, stand along side the Terran 1 slated to fly, and lots more.

The video includes a lot of things worth watching, including time lapse photos of how they 3D print rockets, and engine parts.  There's a lot of details in here; Muller gets input from Scott Manley on several technical points.   

It's also fun to see Tim Ellis in more detail than I've seen before.  He's clearly a space nerd and you get a great feel for his passion about rockets and technology.  It comes across clearly that he's building Relativity because he sees it as an existential part of being human.  His vision is for expansion to Mars, like Elon Musk's, but sees different ways to achieve some of these things.  

Relativity's Terran-R concept rendering.



  1. That's beautiful. I wish them the best.

  2. The factories who produce stainless steel rolled into sheets aren't the enemy; why aren't these people using COTS materials where they fit? Ah right because they're selling 3D printing as a lifestyle, it's

    1. With 3D printing you can get all sorts of things built into the print that you can't get from a rolled and assembled vehicle like Starship.

      It's like a multi-axis milling machine, but in reverse, instead of taking a chunk of metal and hogging tons of stuff off to get the final piece, you do it in reverse.

      And... When NASA went to look at resurrecting the mighty F1 engine, they cut the number of parts from thousands and the number of welds from thousands to a low hundred, just by using 3D printing and mutli-axis machining. (And could have built the F1B at a ridiculously low price.)

      Or Lost Foam Casting, as developed by the now defunct Outboard Motor Corporation. Take an engine powerhead, without cylinder sleeves, and slice it into slices. Make castings of the slices. Cast styrofoam into molds made from the castings. Glue the styrofoam castings together to make a solid powerhead. Now put that into whatever casting medium you use for steel, and now cast a powerhead and use the molten metal to melt the styrofoam. Makes for a very complex outboard motorhead into a single casting.

      The neat thing about 3D printing is, once you perfect it, you can ship the machine to location X and print stuff at that location. Which Rocketlabs has talked about.