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You have indeed raised this idea before. The replies in other threads, among people familiar with this design space, will be the same here, as they were before

You have indeed raised this idea before. The replies in other threads, among people familiar with this design space, will be the same here, as they were before (https://news.ycombinator.com/item?id=29855830 https://news.ycombinator.com/item?id=29855830). Namely: These devices are one of a kind items, fabricated, integrated, and tested manually, not on some kind of assembly line. There isn’t an economy of scale. Your conjecture is just not correct. It’s remarkably hubristic to think the people who design these space telescopes have continued to do it wrong because making duplicates has not occurred to them.

ericd 5y ago
When is the second copy of anything ever the same price as the first? That thread talks about the second being maybe 30% of the cost of the first. Is that not “economies of scale”? And I think that seems like a great deal, given how much universe there is to look at, and the potential for the first to not survive until the end of its expected lifetime. Hell, why not put 10 of them up there, and iterate on the design?
WalterBright 5y ago
Even if building a 2nd one cost the same as building the first, how much of that $10 billion is design and development cost? $0 of that will factor in to the cost of the second. I've fabricated many things with my hands and machine tools. The second one takes dramatically less time, in every case. Even the 2nd set of materials cost less. For example, I ordered a needle bearing the other day for $7, but with shipping the total came out to $20. If I ordered two bearings, the total cost would have been $27, not $40. It took me 20 minutes or so to install it. If I installed it a second time, I could have done it in 5 minutes. The reason is simple. I had the right tools laid out, and I knew exactly what to do the second time. So, yeah, I was quite unconvinced in the last thread. P.S. I did not say they were doing it wrong.
- pengaru 5y ago
  I agree entirely. It's not like JWST components were built from diamonds or something where the material costs dominated the budget. It wouldn't surprise me if there were already more than one made for many of the bespoke components used in the telescope. Nobody makes a one-off component without some iteration and covering of their own ass in case something goes awry in shipping or assembly.
- mturmon 5y ago
  There is no reason a priori to believe that integration and test of one of a kind space cryocoolers scales the same way postage does, or batching out parts at a drill press. I’d suggest that it’s on you to demonstrate why these analogies should hold.
  - WalterBright 5y ago
    > integration and test of one of a kind space cryocoolers The point is they wouldn't be one of a kind if #2 was built. Planning, designing, iterative prototypes, designing tests, designing test equipment, building test equipment, devising test plans, writing the enormous amount of software require for all of that, for the ground stations, etc., all add nothing to the cost of building #2. Normally, people take the cost of a program and divide it by the number of units built, and call that the per-unit cost. That's an accounting fiction. The first one costs the bulk, the rest cost far less per unit. > no reason The reason is I can't think of any endeavor where the incremental cost of #2 doesn't drop dramatically.

ericd 5y ago

When is the second copy of anything ever the same price as the first? That thread talks about the second being maybe 30% of the cost of the first. Is that not “economies of scale”? And I think that seems like a great deal, given how much universe there is to look at, and the potential for the first to not survive until the end of its expected lifetime. Hell, why not put 10 of them up there, and iterate on the design?

WalterBright 5y ago

Even if building a 2nd one cost the same as building the first, how much of that $10 billion is design and development cost? $0 of that will factor in to the cost of the second. I've fabricated many things with my hands and machine tools. The second one takes dramatically less time, in every case. Even the 2nd set of materials cost less. For example, I ordered a needle bearing the other day for $7, but with shipping the total came out to $20. If I ordered two bearings, the total cost would have been $27, not $40. It took me 20 minutes or so to install it. If I installed it a second time, I could have done it in 5 minutes. The reason is simple. I had the right tools laid out, and I knew exactly what to do the second time. So, yeah, I was quite unconvinced in the last thread. P.S. I did not say they were doing it wrong.

pengaru 5y ago
I agree entirely. It's not like JWST components were built from diamonds or something where the material costs dominated the budget. It wouldn't surprise me if there were already more than one made for many of the bespoke components used in the telescope. Nobody makes a one-off component without some iteration and covering of their own ass in case something goes awry in shipping or assembly.
mturmon 5y ago
There is no reason a priori to believe that integration and test of one of a kind space cryocoolers scales the same way postage does, or batching out parts at a drill press. I’d suggest that it’s on you to demonstrate why these analogies should hold.
- WalterBright 5y ago
  > integration and test of one of a kind space cryocoolers The point is they wouldn't be one of a kind if #2 was built. Planning, designing, iterative prototypes, designing tests, designing test equipment, building test equipment, devising test plans, writing the enormous amount of software require for all of that, for the ground stations, etc., all add nothing to the cost of building #2. Normally, people take the cost of a program and divide it by the number of units built, and call that the per-unit cost. That's an accounting fiction. The first one costs the bulk, the rest cost far less per unit. > no reason The reason is I can't think of any endeavor where the incremental cost of #2 doesn't drop dramatically.