(Another copy-paste from the sci-fi blog. Well, really from Quora…)
Ciro Pabon, lives in Cali, Colombia (2008-present)
They were not able to invent surface plates, believe it or not.
I already noted that many advanced civilizations like Romans, Persians, Hindus and Chinese were unable to produce them.
I think that made a huge difference.
In my opinion this is the key development in engineering that allowed the UK to build a different class of machines, with repeatability and precision
Perhaps you may want to read about the invention that separates modern industrial civilization from other engineering achievements.
Ciro Pabon, B.S. Civil Engineering & Highway Engineering, Universidad La Gran Colombia (1984)
Oh, that is a very simple answer, or at least it was until it got a few comments.
Surface plates without a shadow of doubt.
This plate has a surface that has a maximum variation in flatness of 0.01 mm in 3 meters and it is not the more precise of them
Those plates were invented around 1800 but a formal more precise method to build them was described around 1830 by
Surface tables were converted into reality and made eminently practical to revolutionize our lives by
They are precise surfaces that are not created by other mechanical instruments.
They are used to create precise instruments.
As David Moseley commented, there is a nice book on the subject that David thought was called “Precision”.
Of course Barry McNutt explained the book was called Exactly: How Precision Engineers Created the Modern World.
Surface plates are so important because without them we could not have straight spindles nor flat surfaces when building lathes, drills and other primary machines that we use, in turn, to create other machines like engines, motors or any of the millions of mechanisms we use daily.
This means that the modern machines we use and not one or two but all of them depend for the precision of their dimensions on the existence of surface plates which is what metrologists and machinists use as reference when creating machine tools.
Historians of technology say that true machine tools have a tool path that is guided by the machine itself.
The first such machine tool lathe was made by Maudsley in 1810, this is an 1812 model.
To create the spindle and the plane that are the basis of this tool, Maudsley had to create first the surface plate by polishing. He later followed Witsworth method to build a surface plate by scraping, which provided a more precise system, able to create interchangeable parts.
Thus, surface plates are the basis of all the instruments we use to create other machines.
This simple, unadorned flat surface is what made possible all the modern mechanical inventions.
Without them, we would be still in the Renaissance, without engines, locomotives, planes, rockets, kitchens, tiles, wood cutters, drills, etc, etc, because we could not cut threads or machine surfaces with the necessary precision.
They are marvelous because the way to fabricate them originally was entirely by hand and is one of the most ingenious things I have seen to occur to someone.
For centuries people have used colored dust to “paint” one of two (A and B) surfaces.
When A and B surfaces touch, the dust marks the high spot on both surfaces so you can chip away the painted areas on A and B and both slabs will coincide.
As Mark Whickman comments, once people started to build surface plates they stopped using dust and used “engineer’s blue”, which is an oil, not dust.
The reason why you need oil instead of dust is that the plates become so flat (thousands of a millimetre) that they tend to stick together because all their surface is in contact and friction becomes large
Also, instead of polishing, the technique employs scraping using a “hand scraper”.
sing these techniques you can get surfaces that have irregularities that are less than 300 atoms thick.
Once materials are extremely flat, they can adhere to each other by cold welding, but I digress.
Nanowires fusing without any pressure or fusion by cold welding, just by touching each other
Once surfaces are extremely flat and clean, atoms do not “know” if the belong to one surface or to the other, that is kind of deep
However, even with engineer’s blue and hand scrapers, this means that you could have two surfaces that touch each other but they may be curved.
Now, the new idea was this (because a few people asked how surface plates are built):
You scrape away the high points of A and B and then you use a third surface C, scrape away A and C by comparing them.
Then you rotate C and scrape away B and C.
Then you rotate B and scrape away again A and B.
You end with three surfaces that coincide and are flat because there is no other way in which three surfaces can coincide after rotation and scraping in triplets.
The process of scrapping three surfaces alternatively and rotating them 90 degrees after each scrape gives you, incredibly, flatter surfaces than the ones you get by grinding or “lapping” because it doesn’t cause thermal stresses.
This is one of the few examples I know in which a manual process, done by hand and using for control the human mind gives you more precise results than one controlled by machines.
I use this example when someone contrasts science and arts as essentially different because after decades in engineering I sincerely think they are indistinguishable.
How to build a surface plate using Withworth 3 plates method, explaining in a simple and accesible way how it works from minute 3 to minute 6
If we lose this technology we will never recover, although, to be sincere, they are not that hard to make, but they are perhaps the most fundamental invention in history, way better than wheels, fire or agriculture, because those things have been invented independently by several civilizations, while surface tables have been invented only once and look how far down the road of precision technology we have got thanks to them.
You could say that surface plates are what separates our civilization from all the others that preceded us, included Romans, ancient Greeks, ancient Egyptians, Babylonians, ancient Chinese, Mongols, etc, because since the invention of flat plates we had machine tools, threads, lathes, drills, and interchangeable parts and those cultures, with people as smart if not smarter than us, were not able to invent precise machine tools.
In truth, flat reference plates are what allows us to, for example, use Quora to communicate.
You may think I am exaggerating but flat surfaces are essential for integrated circuit lithography, in which layers are aligned with precision of nanometers and without that capability it would be impossible to create integrated circuits as precise as we routinely create them, so no computers for you.
Notice the important invention, which is that you do not measure thickness, something you can do with a micrometer, but flatness.
A piece can have the same thickness along its surface but be warped, so it would not be flat.
Image of legendary Mitutoyo flat plate
Notice that Mitutoyo not only is considered the company that helped Toyota to create JIT technology but also is credited with “forming the foundations for the technically advanced Japan we see today”, which is no small feat for a maker of screws and flat tables, a thing I find poetic.
Without this simple instrument, you would be making your burgers and hot dogs like cavemen, by pounding together two rocks… 😀
Phillip Remaker gave us in the comments this Rick and Morty bit from “True Level” and I love it, Phillip, thanks a lot:
Everything is crooked!
All hail the mighty surface plates!!!
Progressives and liberals can wail and cry and focus on political redistribution and gender studies, about math being racist and life randomly creating itself.
Christians need to buckle down on engineering, computer science, observational science and, yes, math.
(Medicine too, regardless of the will of the Satanists… whose incompetence re: COVID-19 we will be spending at least a decade recovering from.)
We must take the dominion mandate seriously, with our minds as well as our hands.
THIS is how we win. Sacrifice to know the Law of God, master your trade, build your family, get financially independent.
Not by ‘voting Republican’: a.k.a voting for the Democrats of 2000 or so.
(I.e. people like Bill Clinton, or even Donald Trump.)