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How do they make stuff?

Thread Title said:
How do they make stuff?
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Look, it's really complicated. All you need to know is that it involves wibblely wobblely timey whimey stuff.
 
I think one of the concepts you've hit on is bootstrapping. Many tools we use are used in the process of building that very tool. A compiler is a simple software example. A C compiler is written in C, and is compiled by another C compiler. A modern microchip can only be designed, produced, and tested by other microchips.

Here's an excellent example of bootstrapping:



I'm no civil engineer, but I loved how the bridge changed and morphed between different kinds of bridges as it was being constructed. Its hard to see all the cables in the video, but they are very important.

The first bootstrapping step was to pass a single cable across the whole canyon, that's a simple job, a helicopter can do that. After that, you build a bit of a suspension bridge:

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After that, they build a cable stay bridge:

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you'll note that the two towers that make up a cable stay bridge aren't part of the final bridge, they are removed. The suspension bridge is also removed after construction.

So each arch section can be transported by the over head cables, and then held in place by the cable stay bridge, once the arch is complete, the cable stay is no longer required.
 
theprestige said:
As far as suspension goes, first you build the suspension towers, then you hang the main cable between them in its beautiful and characteristic catenary arc. Then you dangle the individual suspension cables from the main cable. Then you work your way across the span, suspending each section of roadway from its allotted set of cables, until the entire span is... spanned. Probably you use some temporary support structures along the way, and remove them once the entire span is in place and the load is properly distributed along the main cable.

My grandad had a fantastic book that documented in words and photographs the construction of the Golden Gate Bridge. A book like that could make for fascinating reading, if you want to see how projects like that actually get done.
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I remember watching the Humber Bridge being built when I was a child. Each road section was lifted up by crane, and secured. They started at the middle, and worked their way out alternating each side. We went to watch every few months

There was no temporary support structure that I recall, as the arch of the road is not a structural function (for want of a better phrase). It is the cables that support the roadway, and so even when all but one sections had been lifted, they were all well supported.

Well, apart from when some sections fell off one evening. Before the bridge was completed.

The towers are an amazing achievement, as they are out of parallel by just a few inches to account for the curvature of the Earth (and continually cast concrete), and the South tower was built in the Humber, 500m from shore, and it wasn't the most ideal geology on the South side (clay).
 
But I still don't know how you build a city of rock'n'roll.
 
An engineer once said that any fool can build a bridge that won't fall down. The real skill is in building one that only just won't fall down. These illustrations of bridge-building remind me of a guy who sculpted lions for a living. He was entering some country and had to complete an immigration form which asked him to state his occupation - he answered sculptor of lions - and to describe what he did. He said, 'I take a lump of rock and chip away the bits that aren't lion'.

So building a bridge is like that - build a whole lot of stuff, dangle a bridge from it, then take away the bits that aren't bridge. Simples.
 
I Ratant said:
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We don't have memorable names.
Isambard Kingdom Brunel..." built dockyards, the Great Western Railway, a series of steamships including the first propeller-driven transatlantic steamship and numerous important bridges and tunnels."
Buffy Smith.. meh!
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The first I heard of Brunel was several years ago from a wonderful documentary which was narrated by Jeremy Clarkson. It is worth a look if you are into Brunel. It was part of series about the greatest Britons of all time. I believe that Brunel finished about 3rd or 4th on the list.
 
oCC
Occasionally, I ponder on the fact that stuff is made using tools and machinery > made by other people using tools and machinery made by someone else .... and so on ad infinitum really!:)
And it all has to be bought and transported. Amazing, really!
 
We had a talk by Lewis Dartnell at Skeptics in the Pub last month, about his book The Knowledge. The premise is that civilisation is destroyed by a catastrophic event; how could we get back to where we now, quicker than the first time around. It's addressing the same sorts of questions posed by the OP; what are the layers of knowledge needed to do something we take for granted like taking a photograph or building a bridge.

Maybe it was a viral pandemic, or an asteroid strike, or perhaps nuclear war. Whatever the cause, the world as we know it has ended and you and the other survivors must start again. What key knowledge would you need to start rebuilding civilisation from scratch?

Once you’ve scavenged what you can, how do you begin producing the essentials? How do you grow food, generate power, prepare medicines, or get metal out of rocks? Could you avert another Dark Ages or take shortcuts to accelerate redevelopment?

Living in the modern world, we have become disconnected from the basic processes that support our lives, as well as the beautiful fundamentals of science that enable you to relearn things for yourself.

The Knowledge is a journey of discovery, a book which explains everything you need to know about everything. This is a quickstart guide for rebooting civilisation which will transform your understanding of the world – and help you prepare for when it’s no longer here...

http://the-knowledge.org/
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zooterkin said:
Maybe it was a viral pandemic, or an asteroid strike, or perhaps nuclear war. Whatever the cause, the world as we know it has ended and you and the other survivors must start again. What key knowledge would you need to start rebuilding civilisation from scratch?
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In terms of rebuilding, there is a huge difference between viral pandemic and the other two, and significant difference between asteroid strike and nuclear war. In case of viral pandemic, most of material infrastructure will remain intact -- survivors will be literally surrounded by usable machinery, not to mention libraries. A nuclear war widespread enough to end civilization would leave very little of it. Asteroid strike is harder to quantify, but I suspect that if you are sufficiently far away to survive, local infrastructure and knowledge will also survive.
 
At least some engineers should be famous. Donald Bailey. Designed a bridge that is really and army sized erector set. Many of those temporary bridges are still in use and many armies still have them in their inventory and probably still will when the design turns 100 years old.

http://en.wikipedia.org/wiki/Donald_Bailey_(civil_engineer)

Edited to add: He did get knighted for this bridge.
 
Doubt said:
At least some engineers should be famous. Donald Bailey. Designed a bridge that is really and army sized erector set. Many of those temporary bridges are still in use and many armies still have them in their inventory and probably still will when the design turns 100 years old.

http://en.wikipedia.org/wiki/Donald_Bailey_(civil_engineer)

Edited to add: He did get knighted for this bridge.
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Thank you, Doubt.

Thank you for bringing back memories of trying to set up a Bailey Bridge, to standard, in a set time period.

I had forgotten about that unpleasantness.

Jerk. ;)
 
How do they make stuff? Damned if I know. Ask some of those Chinese folks. They make pretty near everything these days. I'm not sure anybody else knows how any more.
 
Toke said:
Heard of it too, could be true.

:D
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Tain't true.

But your post is a pretty good illustration of why urban legends spread. This one is covered on Snopes under drilled wire.
 
CORed said:
How do they make stuff? Damned if I know. Ask some of those Chinese folks. They make pretty near everything these days. I'm not sure anybody else knows how any more.
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Not really the case. Inshoring, as well as being an ugly word is a real trend. Intel, Samsung and TSMC dominate what is arguably the most high-tech of industries, the semiconductor industry. Admittedly TSMC is based in Taiwan, but the ROC is not the PRC.

Elsewhere, Germany does a fair bit of manufacturing as does even the US and even the UK.
 
I've assembled and done fine alignment on huge Nuclear fired steam generators before ... it's amazing how fluid steel becomes in sizes that large ... the turbines all sag dramatically in the middle

You have to set all the bearings (which are each the size of a small living room) on angles to line up with them
 
Doubt said:
At least some engineers should be famous. Donald Bailey. Designed a bridge that is really and army sized erector set. Many of those temporary bridges are still in use and many armies still have them in their inventory and probably still will when the design turns 100 years old.....
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There are 2 within 5 miles of me, both in everyday use on country lanes, and both looking good for another 70 + years. Wide enough for a tank, but not quite wide enough for cars to pass, so single track only.
 
CORed said:
What I don't get is, since it takes one woman nine months to do it, why can't nine women do it in one month?
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We like to experiment, also.
This should be fun/interesting.............and way expensive!:p
 
Many engineers have that "long torso". And get inane criticism for that!
"If that belly was on a woman, she'd be pregnant!"
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The proper response:
"It was, and she is!":rolleyes:
 
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