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An interesting precedent: The Monitors.

John Ericsson designed the Monitor so that Monitors could be built rapidly in any well equipped machine shop

The original Monitor was built in 100 days, despite being novel in almost every respect, from the freeboard so low (18 inches) that she made no target, to the never-before-attempted revolving turret, to the novel recoil mechanism on the guns.

A Monitor could be built in any well equipped machine shop, anywhere near water (including lakes and rivers). The turret of the original Monitor was built in a Manhattan iron works, the boiler and machinery in another Manhattan machine shop, then both were disassembled and reassembled on the hull in a Brooklyn yard.

Once the original Mionitor proved its worth, Ericsson turned them out like popcorn. Although they were not blue-water ships, they didn't need to be; they were for coastal defense and blockading.

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What stood out, to me:

1. "But they couldn’t avoid the fact that the shipbuilding process required doing large numbers of tasks at once, rather than in sequence like Knudsen’s auto assembly line."

2. "There three conveyor belts in each bay were set up to handle three deckhouses at a time. The belt was not a belt at all, but a three-foot-high concrete platform, on which were mounted trolley wheels at two-foot intervals—and on the wheels were the enormous mounted jigs carrying the deckhouse and pulled by a two-drum 10-horsepower hoist at the opposite end."

Similar takeaways from modular construction factories. These can serve as indicators why spatial design of a modular construction factory floor following traditional auto assembly line rules might not be the right approach. We are already learning from an ongoing project that the traditional site construction sequencing should not be followed as is for factory build sequencing. Example, shifting solar PV install steps upstream closer to roof build station on the factory floor (vs a downstream activity, after the roof has been set). Makes sense for cost, time, collaborative work. There is even more room to get creative with the sequencing.

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I'm very much looking forward to Part 2!

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I like the idea of asking for workers for ways to innovate and then actually giving them the ability to test and use their ideas. I wonder if that is an important lesson that the construction industry can learn?

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I'm not sure Liberty Ships are the best place to look at for parallels to the building industry. In a lot of ways, they're very much the exception, not the rule, in shipbuilding history. It would be like looking at the history of the quonset hut to try to bring down the cost of housing. The only other large vessel I'm aware of that was built in anything like the same sort of numbers was the LST, and it was a third of the size and had about a thousand built, although using quite similar methods. So a lot of the stuff done in the Liberty program was very abnormal in shipbuilding, although it's also quite prominent and thus easy to learn about. There's a recent book from the US Naval Institute called Warship Builders that looks at the conventional warship program during WWII, which provides a useful counterpoint.

Re British productivity, I believe the differences in cost and practice were present prewar, and appear to apply across all kinds of ships. A British submarine builder produced about twice as much tonnage per year as his American counterpart. (Ref DK Brown, Nelson to Vanguard, which goes into more detail on this.) I am quite confused by this, and would chalk it up to different accounting methods (if prefabrication takes place away from the yard, then how is the labor involved calculated?) because those sorts of things are notoriously hard to compare across countries. But this falls in the face of the fact that prices for American-built ships were twice those of British-built ships of very similar types, broadly tracking labor hours. Of course, it could well be that incomes in America were much higher, but that doesn't seem to track with per-capita GDP figures. And then there's things like differences in battleship turret construction which left the British often limited by the supply of mounts (hence HMS Vanguard) and the Americans never had any problems. I do not know why, and it kind of annoys me.

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Amazing! Great research.

Would have imagined faster production techniques would result in cost savings, less inventory and probably less labor. Are there difficulties comparing US costs with Britains?

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Would have imagined faster production techniques would result in cost savings. Less inventory and probably less labor. Was it difficult to compare US costs with Britains?

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