The Science Of Flatness

Flatness is an often misrepresented property of our own intuition. Many of the objects we consider flat, pale in comparison to surfaces manufactured to actually be flat. It's also a property that our industrialized world relies on to function.
While most of us experience flatness as part of aesthetics and ergonomics, flatness in manufacturing is a critical property of positioning, mating and sealing parts together. The high pressures produced by combustion are contained by two mating flat surfaces aided by a gasket.
Let's look at a sheet of float glass. The floating process self levels the glass, giving it a relatively flat, uniform thickness.
Let's say a manufacturer's specification calls for a 3mm thick sheet of glass. For a sheet to pass a quality check, its thickness is sampled at various points along its length and as long as it is 3mm thick, plus or minus a specified tolerance, the sheet passes.
But what if during the process of moving the floating ribbon of molten glass a subtle disturbance is introduced to the molten metal. Let's say this disturbance imparts a 0.25 mm wave-like undulation throughout the entire ribbon. Now to eye the cut sheets would appear flat and they would pass the quality check for thickness, but the surface of that sheets of glass is far from flat.
Flatness isn’t derived from how closely a part matches its specified dimension. It is a property completely independent of the part’s gross shape.
If we take a surface and sandwich it between two imaginary parallel planes. The gap between the planes that encompasses the surface is known as a tolerance zone. The smaller this distance the flatter the specification.
On parts that do explicitly define flatness the method of both measuring and producing flatness is determined by how tight of a tolerance zone is required.
Flatness specifications down to around 10 microns or about 4/10,000th of an inch are quite common in machinery.
Those mating and sealing surfaces found in car engines can be found at this level of flatness. Sealing in fluids at this level of flatness requires the use of a gasket.
Field testing flatness at this level is done with a known precise flat edge and a clearance probing tool known as feeler gauges.
Actually measuring the flatness of a surface is a lot more complicated. An obvious solution would be to measure the surface against a flat reference. For example, if a part has a surface parallel to the surface to be measured it could be placed on a surface plate. A surface plate is a flat plate used as the main horizontal reference plane for precision inspection. A height gauge could then be used to probe the top of the surface for flatness relative to the surface plate.
If we first place the part to be measured upon 3 columns with adjustable heights. Then, with a height gauge, run the probe across the surface while looking at the amplitude of the needle, we get a snapshot of the difference between the highest and lowest point on that surface.
Automating the process with the use of a coordinate measuring machine or CMM is a common practice. CMMs are typically computer-controlled and can be programmed to perform the tedious repetitive measurements.
Going beyond the 10-micron levels of flatness requires the use of surface grinding. This process typically used to produce precision parts, precision fixtures, measurement equipment, and tooling.
Lapping is the process of rubbing two surfaces together with an abrasive between them in order to remove material in a highly controlled manner. In lapping a softer material known as a lap is "charged" with an abrasive. The lap is then used to cut a harder material. The abrasive embeds within the softer material which holds it and permits it to score across and cut the harder working material.
Wringing is the process of sliding two ultra flat faces together so that their faces lightly bond. When wrung, the faces will adhere tightly to each other.
This technique is used in an optics manufacturing process known as optical contact bonding.
When an optical flat's polished surface is placed in contact with a surface to be tested, dark and light bands are formed when viewed with monochromatic light. These bands are known as interference fringes and their shape gives a visual representation of the flatness.
Stähli Side Flathoning Machine
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Courtesy of Stähli Lapping Technology Ltd -
oxtoolco (Tom Lipton) - Precision Lapping 101
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oxtoolco (Tom Lipton) - Russian Optical Flat Testing
• Russian Optical F...
Pierre's Garage - Very cheap unique wavelength light for using with Optical Flats... Using a 532nm. 50mw LED laser
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Joe Pieczynski - How to Accurately Inspect a Flat Surface
• How to Accurately...

Пікірлер: 3 012

  • Timo Rieseler
    Timo Rieseler3 жыл бұрын

    So, when flat earthers claim the earth is flat, maybe they're just working with higher tolerances...

  • Doesn't Hurt Yet

    Doesn't Hurt Yet

    2 күн бұрын


  • Julian Higginson

    Julian Higginson

    13 күн бұрын

    Excellent 😂

  • Yeet Man

    Yeet Man

    14 күн бұрын

    @Harry well put it simply the more time progresses the more minute will the thing be that we are wrong about.

  • Yeet Man

    Yeet Man

    14 күн бұрын

    @Harry thats how science work, it improves itself overtime

  • ࠱೬ഽུƙก྄࿑࣮࠱


    17 күн бұрын

    @NO WAY flat mind blown.. 🙈😂😂

  • Paul Drake
    Paul Drake2 жыл бұрын

    I took a tour of NASA's Glenn Research Center in Cleveland, they created a sealed room with an absolutely flat floor, within some microns of tolerance. I can't remember what kind of testing it was used for but they seemed pretty proud of it.

  • cmdr tremyss

    cmdr tremyss

    2 ай бұрын

    If I had an absolutely flat room, I'd be pretty proud too. I'd also politely ask my guests, to take their shoes off.

  • non yobussiness

    non yobussiness

    2 ай бұрын

    @S H899 doesn’t space time bend

  • Atash Gallagher

    Atash Gallagher

    2 ай бұрын

    But is it also true level?

  • TBot Alpha

    TBot Alpha

    2 ай бұрын


  • Florida House

    Florida House

    2 ай бұрын

    @S H899 When you are able to manipulate individual atoms in a crystalline structure to basically 3D print a single atom at a time with the STM as they showed, it would seem you cannot have anything more flat than that. If you are going to talk about normal matter in this universe in environments where human can coexist, I would say that is as good as it gets...

  • Privatepilot
    Privatepilot8 күн бұрын

    Very well done. As a retired Certified Mechanical Inspector and Metrologist, I found many people not familiar with GD&T would have a difficult time understanding flatness. They would always get it mixed up with parallelism. Flatness is essentially a characteristic measured to itself. I sure miss those days.

  • Alexis Andersen
    Alexis Andersen2 жыл бұрын

    "The definition of flatness quickly become..." Become what.... BECOME WHAT?

  • Alexis Andersen

    Alexis Andersen

    12 күн бұрын

    @FLAT OUT FTW because what the world wants and what it needs are not always the same thing.



    13 күн бұрын


  • Greggy P

    Greggy P

    2 ай бұрын

    @Alexis Andersen It was a good joke

  • Brandon Whitney

    Brandon Whitney

    2 ай бұрын

    I think he said moot, but the fade out was very abrupt.

  • Gospodin Jean

    Gospodin Jean

    2 ай бұрын

    we will never know............

  • Stephen Krambeck
    Stephen Krambeck2 жыл бұрын

    I’ve had a pretty interesting perspective on flatness going from woodworking to becoming and engine machinist.

  • Bryan Draughn

    Bryan Draughn

    3 ай бұрын

    @Matthew Cornelius Oddly, when your mind is working towards an exaggerated level of perfection, your woodwork will "pop" when completed. People will ask "how do you do that?" It's a culmination of many tiny compensations working together. Works every time too!

  • Matthew Cornelius

    Matthew Cornelius

    6 ай бұрын

    Totally opposite for me. I have been a tool and die maker for most of my career and now just getting into wood working. Needless to say it has driven me to the edges of insanity.

  • rando prior

    rando prior

    Жыл бұрын

    It very quickly goes from "eh, wood glue will fill the voids" to "yes it is perfectly flat but is it REALLY FLAT?!"

  • Brooklyn Zoologist
    Brooklyn Zoologist Жыл бұрын

    My wife says she's flat I told her she's within tolerance

  • Shazee Nora

    Shazee Nora

    Ай бұрын


  • Shazee Nora

    Shazee Nora

    Ай бұрын


  • MrPlusses


    2 ай бұрын

    @Brooklyn Zoologist But how tight is her tolerance? Asking for a friend.

  • Wesley Huang

    Wesley Huang

    2 ай бұрын


  • Reza R

    Reza R

    Жыл бұрын


  • New Mind
    New Mind3 жыл бұрын

    To everyone wondering why the video cuts off abruptly, I lost the last 2 seconds of my audio file. It's supposed to end with "At these scales, the definition of flatness quickly becomes moot."

  • Mr Styles

    Mr Styles

    5 күн бұрын

    Very strange because moot is exactly the word I heard

  • Attila Juhasz

    Attila Juhasz

    2 ай бұрын

    Excellent content, sir. By the way, please "pin" this (above) comment of yours as there are many, many people wondering why it's cut off.

  • craigsbully


    2 ай бұрын

    @SaltyBrains How about a thumbs up?

  • Henry van Megen

    Henry van Megen

    2 ай бұрын

    Getting everyone to comment on your video thus increasing engagement, all while hiding it as an 'error'.. I see what you did there, you sly devil you ;)

  • Varun M

    Varun M

    2 ай бұрын

    I hear it like , "At these scales, the definition of flatness quickly becomes MUTE."

  • Peter Raffin
    Peter Raffin Жыл бұрын

    Very well explained.. I think that all of this can only make sense once you've gone through trying to manufacture parts to flatness levels between 5 and 20 microns in large parts. We've found there's very few machine shops in the world that are capable of doing this work reliably over a long period of time. As you say, half the battle is actually measuring accurately in a repeatable manner.

  • Peter Raffin

    Peter Raffin

    2 ай бұрын

    @L R mass spectrometry

  • L R

    L R

    2 ай бұрын

    Which sort of sophisticated industry are you working with?

  • Dog Clutch
    Dog Clutch3 жыл бұрын

    Geometric tolerances are incredibly important in manufacturing and design processes. Excellent presentation, keep making videos of this calibre sir!

  • epistte


    2 ай бұрын

    This is better explained than the labs of my manufacturing process courses and GD&T class.

  • Jeff Klaubo
    Jeff Klaubo2 жыл бұрын

    "Do you want to experience true level?" -Rick

  • Nicholas Kigen

    Nicholas Kigen

    Жыл бұрын

    I was looking for this

  • Matityahu


    Жыл бұрын

    @Lucas C try harder to make yourself look ignorant 🤣

  • Kristian Tucker

    Kristian Tucker

    Жыл бұрын

    @-Tq- I came to the comments find your reply to this comment

  • Just Saying

    Just Saying

    Жыл бұрын

    Yup... Came here to make this joke, you beat me to it.

  • Bart Hooghwerff
    Bart Hooghwerff3 жыл бұрын

    Very interesting video, as a knifemaker its easy to achieve high level of surface roughness but flatness is a real challenge and something to keep improving on!

  • KnappstersaurusRex
    KnappstersaurusRex2 жыл бұрын

    As a CMM programmer, it's always cool to see popular videos like this introducing people to what I do! Great video.

  • Kyle Z

    Kyle Z

    2 ай бұрын

    @Sighs Internallygage blocks

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Jon Anderson
    Jon Anderson3 жыл бұрын

    The gaskets aren't just for imperfect surfaces. They are for materials that grow, shrink and warp with heating and cooling... Every component in an engine bay for example.

  • Attila Juhasz

    Attila Juhasz

    2 ай бұрын

    There will be a video about the engineering/uses of gaskets within three years, sir.

  • ScareCrow


    2 ай бұрын

    @L R I mean yeah, but in the case of thermal paste, its really easy to clean off and you dont need much of it, a little bit of isoprope on a Q-tip will get rid of all of it right away!

  • L R

    L R

    2 ай бұрын

    @ScareCrow though liquid sealing is a pest to disassemble. Risking to damage essential machine parts because of the gluing effect. Original gaskets should always be prioritised for valuable machinery.

  • ScareCrow


    2 ай бұрын

    technically thermal paste is also a form of gasket! but instead of paper or rubber or metal, its a liquid paste.

  • Diana Pennepacker

    Diana Pennepacker

    2 ай бұрын

    He did a video on Gaskets guys. Just rediscovered the channel today because it popped up on my feed.

  • Tamás Kónya
    Tamás Kónya3 жыл бұрын

    Hands down, one of the most unerrated channels. Thanks for the educative yet quality content. Just binge watched your videos. Congrats and cheers :)

  • Bob.207
    Bob.2073 жыл бұрын

    I am a mechanical design engineer and I am dealing with those specifications on daily basis. I studied metrology as an undergrad it was quite new and challenging. I am so happy to see a video about that and explaining horizons I 've never seen.

  • Mech D

    Mech D

    Жыл бұрын

    Did you notice the error in the video? He spent most of it covering smoothness instead of flatness.

  • André Bartels
    André Bartels2 ай бұрын

    Thank you for this quick look into this very interesting field. I especially enjoyed to see the different testing devices. The lens that uses monochromatic light is fabulous. When it sits in its case, it just looks like a piece of glass, until you use it properly.

  • Graeme Mudie
    Graeme Mudie2 жыл бұрын

    If you want to try the effect of having two really flat surfaces stick together try two platters of a hard disk. They also make perfectly flat mirrors. To get an idea of how flat they are try using them to reflect the sun into a distant building, it like a laser.

  • quaxenleaf
    quaxenleaf Жыл бұрын

    Absolutely fascinating- and great info for those who may have a limited understanding of materials and manufacturing. Thanks for this!!

  • WalterWitt
    WalterWitt3 жыл бұрын

    I think you missed an important part of flatness which is the 3 plate method, who's discovery allowed us to create flat surfaces without the need for a known flat reference. We couldn't rely on any of the methods you showed in this video without the use of external flat references making up the machines and tools used to measure them. The 3 plate method gave us those first reference surfaces.

  • Rathlin Postman

    Rathlin Postman

    2 ай бұрын

    @William Hinrichs Is it not true that anyone at all can write or alter an entry on Wikipedia. In UK there have been press reported cases of political parties having changes made to entries which are done to confuse their opposition. It may be a safer course to use a reputable reference work from a library or a tested resource from a college or from industry. "Some guy on the Internet said ..." is hardly a good guide to reliable accuracy. Wikipedia is a lucky dip, a Bran Tub game. Whilst it surely contains much of use how is the lay user to sift good from bad ? References take time and effort to check. Wikipedia material really has little provenance.

  • Rathlin Postman

    Rathlin Postman

    2 ай бұрын

    @Sighs Internally Reference grade gauges in particular should not be left too long wrung together or they will become one.

  • Rathlin Postman

    Rathlin Postman

    2 ай бұрын

    @Sighs Internally Slip Gauges

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Rathlin Postman

    Rathlin Postman

    3 ай бұрын

    Isn't this grinding process to create surface plates with high order CLA value referred to as "The Whitworth Method" ? Yes it would be the starting point for all modern engineering measurement and machine tool manufacture.. Likely too much hard workfor most folk. As bad as early manual lens grinding l

  • jim
    jim3 жыл бұрын

    Great video! As retired mil and new machinist, I found this very informative and well presented. While working on my education as a machinist I took several engineering and GD&T classes. Every little bit of info helps.

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Rickey Bowers
    Rickey Bowers3 жыл бұрын

    Incredibly thorough coverage of the topic, in a systematic and entertaining manner - well done.

  • Chris Fiumi
    Chris Fiumi Жыл бұрын

    around 9:30 the concept of wringing... that blew my mind. I had a co-worker several years ago who used to work in calibration and described this to me as one of the tools they used, calibration blocks. That's incredible hat surfaces can just bond like that. I guess it essentially created a vacuum between the parts because they are such a precise fit even air can't get between them.

  • Glenn Cooper
    Glenn Cooper2 жыл бұрын

    Fantastic video! I'm an electrical engineer but always trying to broaden my horizons. You did a fantastic job of introducing me to the world of flatness. Who knew that was thing?

    E.PLUMBUS UNUM2 ай бұрын

    Very good job of explaining the basics of flatness. My background in is tool and die making and design and all of what you covered was the world I lived each day. I ran surface grinders and have to maintain tolerances within .0001".

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Ahmed4th
    Ahmed4th3 жыл бұрын

    As someone who works in the engineering and manufacturing industry, I loved this video. I’m subscribing to this channel, I hope to see more of this kind of content here.

  • iDuL II

    iDuL II

    2 ай бұрын


  • Beemer
    Beemer3 жыл бұрын

    I find the fact that things can literally be lightly bonded because they're so flat super intriguing. I wonder how two surfaces would react if they were both perfectly flat.

  • muuce
    muuce3 жыл бұрын

    This is an extremely well made video on the topic. Very well done!

  • Jon Rutherford
    Jon Rutherford Жыл бұрын

    Found this channel because KZread algorithm "recommended" it for me. For once, KZread got it right! Truly interesting subject matter explained about as clearly as possible and with good graphic support. A winner -- thanks.

  • Poly Hexamethyl
    Poly Hexamethyl3 жыл бұрын

    Nice video. I like how it covered an almost unimaginable range, from a piece of wood emerging from a sub-atomic levels of flatness from an electron microscope.

  • Frlja
    Frlja Жыл бұрын

    Incredible video! I am an economist myself, but I love to learn about these kind of things I followed everything quite well, until the greenlight part of video came up. Then I was like - ARE YOU A WIZARD :D incredible stuff

  • jadefalcon001
    jadefalcon0013 жыл бұрын

    Extremely high production value. Well researched and presented. Terrific work! Subscribed. Looking forward to seeing more of your work!

  • Bill Herreid
    Bill Herreid3 жыл бұрын

    Great video! At work I spent most of my time lapping and checking surfaces with optical flats.

  • Karen Hinrichs
    Karen Hinrichs3 жыл бұрын

    Great video. I noticed that you mentioned several different methods of measuring flatness from surface plates and feeler gauges to CMM touch probes. However, you didn't mention measurement of point cloud data collected from a laser scanner or from CT (x-ray) scanning. These are also valid ways to measure flatness, are they not?

  • Jared House
    Jared House Жыл бұрын

    being a machinist we use precision measurement tooling and there are some tables that we use specifically for measuring or hand sanding something. those tables are made out of calibrated slabs of granite.

  • Indranil Dasgupta
    Indranil Dasgupta3 жыл бұрын

    I do not mostly hit “Like” and write something in complement. However, being an enthusiast of this field, I couldn't resist myself hitting the “Like” button and scribing a few words in complement. I would expect more quality productions like this in future. All the best!

  • KEX CZ
    KEX CZ2 жыл бұрын

    Wow. Exactly today, we worked with the magnetic grinder, and we grinded the surface of an steel cube. And the interesting thing is, how precise that grinding is, and even more mindblowing is, that thats not the best surface-fining method like honing, laping etc.... 😃

  • Real Health Quotes, LLC
    Real Health Quotes, LLC3 жыл бұрын

    Nice video, but it ended flat.

  • Lukas B

    Lukas B

    11 ай бұрын

    Well, not really sharp criticism is it?

  • Aaryl Dol

    Aaryl Dol

    11 ай бұрын

    Your comment is flat.

  • Pete Moore

    Pete Moore

    11 ай бұрын

    @Catalyst Network Solutions I can see 1/32 out of level in certain situations. Drives me crazy because it’s the pictures hanging on my wall. I take medicine for my attention to detail.

  • 金善诚


    Жыл бұрын

    Lool so suddenly

  • isayfuck


    Жыл бұрын

    Become mute!

  • Sahas V
    Sahas V3 жыл бұрын

    Been watching this channel when the evolution of CPU part 1 came in and till today this is the best researched and well put videos I have ever come across on KZread. You deserve at least 5 million subscribers for the quality that you are putting out.Keep up the good work I know you will succeed 👍👍

  • wayne thomas

    wayne thomas

    3 жыл бұрын

    I think the reason he doesn't have as many subscribers is because most people don't really care about this stuff. The bulk of people don't feel like they need to know anything, they just think they should be paid for...I don't know what...being alive maybe? Being well educated and skilled in an area that you need to know this stuff is becoming a dying breed. Even skilled machinists don't think about this that much because they're limited by the tools available where they work. A surface grinder or blanchard grinder is the equipment in most shops that can provide any highish level of flatness.

  • Craigy-J Gaming
    Craigy-J Gaming2 жыл бұрын

    I like the video! I'm a hydraulic press operator and have to flatten parts for machining. I didn't know about some of the other ways in your video. Pretty cool!

  • Stephen Roberts
    Stephen Roberts Жыл бұрын

    Thank you, that was very interesting! Is there a similar measurement of sharpness?

  • Dustin Bodie
    Dustin Bodie3 жыл бұрын

    these are so cool. the great thing about these i think, is they introduce you to ideas that you wouldn't have come to by yourself very easily when actually trying to do things like this.

  • Mike Alangaloe
    Mike Alangaloe Жыл бұрын

    I never ever ever thought I could be sucked into a video on flatness. Some simple things are way more interesting than you realize

  • Siggy in CR
    Siggy in CR3 жыл бұрын

    Very informative and well edited video. If ever you chose to revisit this topic, a concern when you start approaching high level of flatness is that temperature differentials throughout the part being measured can significantly skew the results making climate acclimatization an import step before measuring. I've seen toolmakers and engineers struggling with inconsistent readings for weeks only to find out that parts need to sit in the QC room for a while till they acclimate. Otherwise mounted on measuring fixtures can pull the heat out of one part of the piece while the rest is still warm causing it to warp.

  • Mark Koot

    Mark Koot

    3 жыл бұрын

    I used to flat lapp seals for pumps and they were perfectly flat under the glass when they came of the machine but once they cooled a little the light bands I saw didnt make me happy anymore so yeah temp is a big deal

  • milo9598
    milo95982 жыл бұрын

    This is very very informative! I learned a lot from this.

  • David Rave
    David Rave3 ай бұрын

    Your content is always so great!

  • Jeff Quantrill
    Jeff Quantrill2 ай бұрын

    Wow! Thank you for this, my dad was a Metrologist who spent his life making slip gauges and even taught me to lap and perform optical flatness tests

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Dead Freight West
    Dead Freight West3 жыл бұрын

    9:24 - Wringing is the method of joining Johansson blocks (Jo' Blocks or Gage blocks) to obtain a reference dimension. I've never heard it used to describe the adhesion of the blocks themselves. You can wring a meter of Jo' blocks and hold it horizontally without it breaking. It isn't "molecular attraction" it's vacuum. BTW, I'm a machinist, and these are a common setup and test item.

  • Tim Riggs

    Tim Riggs

    3 жыл бұрын

    I believe you are incorrect. Two (as flat as we can achieve) flat surfaces of the same material will bond together at the molecular level, the bond can be made stronger if done in a a vacuum and/or pressure applied.

  • Moreno
    Moreno2 ай бұрын

    Thank you for your work! Great video! What software do you use to make animations with the blue background?

  • A. Page
    A. Page3 жыл бұрын

    Last two minutes really squashed this machinists mind. Good video.

  • sauercrowder


    2 жыл бұрын

    @Chirag Patil There's a lot more nuance there than you were seeing. And, while yes it is surprisingly simple compared to some other processes, getting it to work reliably without ever causing a scrap is another story.

  • Chirag Patil

    Chirag Patil

    3 жыл бұрын

    @Random Mcranderson I did a fab course in uni we made wafers from start to scratch, fabrication was cool but I could not comprehend how the steel carbide lapping process shaved our uneven glass barrier layers on the wafers down to nanometers in size. The equipment needed for the physical side of chip fabrication is large, giant furnaces and vapor chambers and ion guns, but to polish each barrier layer down on the wafer just needed a flat piece of steel, a liquid slurry compound, fine tungsten carbide grit, and a pressure pad attached to a rotary motor. Worked perfectly without much supervision, you just come back every few minutes look at the growth chart, stop 5min before the projected end, check the thickness and grind slowly until you hit the right size.

  • joandar1


    3 жыл бұрын

    @Random Mcranderson I will look, Thanks. Cheers from John, Australia. Edit Link:

  • Operator 801

    Operator 801

    3 жыл бұрын

    Yeah, nobody but OOOOLD timers that don't understand new systems really do it like that anymore. Modern electronics do a better job, faster, and often cheaper than a good optical flat kit. Less maintenance, and cheaper calibration and certification too.

  • Steve Thea

    Steve Thea

    3 жыл бұрын

    @John Dziubinski I sent this vidnto my gf as a joke 😏

  • 393Windsor
    393Windsor3 жыл бұрын

    You showed a clip of Tom Lipton from his KZread channel oxtools. He has many great videos showing how to create flatness, the science behind it and tooling used to achieve it and how to measure flatness. Tom is a pretty awesome teacher.

  • Retoxx
    Retoxx3 жыл бұрын

    I work for Keysight Technologies, and we manufacture glass in very high-end specification for laser measurement systems... I am going to go quiz the glass manufacturing team, because this was the coolest video!! I had no idea of some of the specs that could be reached with flatness!! Thanks for sharing!!

    USINGTHA FORCE Жыл бұрын

    I just came from how glass is made and they explain the tin floating glass part so this is spot-on I understand perfectly

  • FortisNome
    FortisNome3 жыл бұрын

    Never knew flatness could be this interesting! Great job :D

  • J Kurt C
    J Kurt C10 ай бұрын

    @NewMind Hey, I just wanted to tell you that I really enjoy your take and explanation of science topics, it is super engaging for me (31) as well as my daughter(8) perfect balance no matter what age or knowledge level!

  • Ben Spierings
    Ben Spierings3 жыл бұрын

    as someone who gets structural design courses, and works at a tool manifacturer, this is amazingly well produced and well informed i love it

  • Josh Worthley

    Josh Worthley

    3 жыл бұрын

    @Larry Lund Flatness is a form only control, it cannot have a relationship to datums. If a print references either the ASME or ISO GD&T standard and it had a feature control frame with Flatness AND datums, the print is in error and wasn't produced per standard. I agree that it is a great introductory video, but one getting into the level you are asking for would be significantly longer.

  • jockellis


    3 жыл бұрын

    I liked it, too. I worked in a GE Energy machine shop that had 16 CMMs, both in final inspection and on the shop floor. I did NDT but was enamored with all final’s cool tools.

  • epistte


    3 жыл бұрын

    Drafting 101 GD&T.

  • Larry Lund

    Larry Lund

    3 жыл бұрын

    Nobody actually asked a quality inspector. Tons of guessing going on in this video. It provides most of the basics but, we need more information on how the Flatness is actually called out. Is it to itself or in relation to other datum points?

  • Jakub Sengerski
    Jakub Sengerski3 жыл бұрын

    I love this video for both overview of techniques for achieving flatness and good explanations for them, but if I could have one request it would be to put all the numbers on the screen for non-native speakers, it's just waaay easier if you actually see 2,5 (microns) than to listen, I always have to think about it just for a second and I tend to get lost in the sentence. This applies also generally the whole video as it would be nice to sometimes see some caption like 'wringing' (or when you list few thing - wan der waals force, hydrogen bonds and dipole interactions), as now I feel like the experience is lacking something with just voice + related video in the back (beginning of the video was great with measuring techniques visualizations but I was hoping to also see the 'imaginary line' in case of the optical stuff - wish you went deeper with this topic :)), it would be nice to have some kind of interruption from time to time, although the content is great! Thanks again, it's a great informative video, I hope this helps and the channel grows even more :)

  • Andrew Schafer
    Andrew Schafer3 жыл бұрын

    Great overview presentation. Anyone working in manufacturing should see this. Flatness can be a very difficult concept to truly understand.

  • Tim Bo
    Tim Bo2 жыл бұрын

    Really good video. The two things missing were hand scraping and the use of an auto-collimator to measure the flatness of a surface plate.

  • seearress
    seearress2 жыл бұрын

    Very informative video! Well done. Reminds me of my rotating mechanical seal manufacturing days where we would use monochromatic light waves to measure flatness. ; The ringing adhesion phenomena is caused by ambient atmospheric pressure. Normally, any object has atmospheric pressure acting on all sides of it EQUALLY. If this wasn't the case it would be in motion or producing drag. However, in this phenomena(2 ultra surfaces pushed tightly together), the atmospheric pressure is acting on all sides EXCEPT the mating surface which is so flat it doesn't not allow molecules of air to fit, thus the relativity low atmospheric pressures we have on earth doesn't have a medium to exist in on that side of the piece: essentially the earths atmosphere is pushing both flat pieces into each-other., and if you make two pieces with a big enough flat surface area, they will be VERY hard to pull apart by hand. performing the ringing mating process of two flat pieces in a vacuum chamber would significantly if not entirely make the adhesion go away.

  • thewheelieguy


    Жыл бұрын

    That's one potential explanation but not I think correct -- the same ringing adhesion will happen in a vacuum, and parts bonded this way become increasingly difficult to separate as time passes. The molecular adhesion thesis concords with both of these phenomena.

  • Terkan
    Terkan Жыл бұрын

    Imagine making an engine that is bonded by spontaneous cold-welding due to perfect flatness in a vacuum. You couldn't open it to check it I guess but fuck it, it would be impressive.

  • Chase Thompson

    Chase Thompson

    2 ай бұрын

    Just wait til subie owners hear about this

  • cyalknight


    Жыл бұрын

    I had an idea for a 3D printer using cold welding in a vacuum. The "pixels" would need to be cubes or something with a flat edge.

  • Clarence


    Жыл бұрын

    It would be cool if it worked, it would be good if the head and block were the same material otherwise heating and cooling would warp the surfaces and create a mess

  • justjefff


    Жыл бұрын

    @AJ213 "I'm tired of this (lack of right to repair) grandpa!" Elon: "well that's too damn bad!"

  • AJ213


    Жыл бұрын

    Space manufacturing is going to be great

  • TheTarrMan
    TheTarrMan3 жыл бұрын

    As someone who works in a machine shop and deals with "the great struggle" daily, I can say this video was well done.

  • TheTarrMan


    2 ай бұрын

    @Sighs Internally Those are called "gage blocks". The ones at 9:40 appear to be ceramic (higher quality, ridiculously expensive) while the ones at 9:30 appear to be the steel "shop grade".

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • Michael McCurley

    Michael McCurley

    3 жыл бұрын

    "The great struggle". Yeah, that about sums it up. I'm in the same trade. Perfection is an unachievable goal that some of us struggle to achieve anyway. After tossing the manager in to the chip bin, and getting on with it... ;)

  • David Wootton
    David Wootton3 жыл бұрын

    A very nice video, thanks very much. When polishing Sapphires (gemstones) you can actually see the interference patterns just before the facet is nearly optically flat.

  • Hamburger Helpern
    Hamburger Helpern Жыл бұрын

    very cool! I'm an optician and make curved lenses that can be 1/20th of a wave, This video helped me explain what I do to a few of my curious friends

  • JacSolar
    JacSolar2 жыл бұрын

    Incredible video. Metrology is such an interesting field.

  • Sold to be Diers
    Sold to be Diers Жыл бұрын

    Tickles me now to recall the Metrology class back in the early '90's; where the statement that even the thought to be flattest surface, still sits on just 3 of its highest points.

  • Me Off
    Me Off Жыл бұрын

    Takes me back my CNC machinist days.

  • delirio
    delirio3 жыл бұрын

    great video. the only thing missing is the beauty of hand scraped surfaces, which would add to the difference between flatness and roughness

  • Industrialitis


    3 жыл бұрын

    @body no That is a wonderful video!!!

  • body no

    body no

    3 жыл бұрын

    @lordchickenhawk The dawn of precision manufacturing.

  • lordchickenhawk


    3 жыл бұрын

    Also, the "three plate method" deserves a nod in that context. Hand scraping (and lapping) combined with the three plate method is what gave engineering its first accurate reference surfaces for flatness

  • Brilliant Design!
    Brilliant Design!3 жыл бұрын

    I have a special butter knife I use to spread the atoms out evenly for perfect flatness. Only works with monochromatic blackberry jam, though.

  • PixelDimond


    Жыл бұрын

    Lmfao 😂

  • Fritzfield Wrangle-Clouder

    Fritzfield Wrangle-Clouder

    Жыл бұрын

    Jam or jelly? What about the pips?

  • Eddy.G Delaleu

    Eddy.G Delaleu

    2 жыл бұрын

    Jokes on you im a mechanical engineer and looked for this

  • Mike Sokolow

    Mike Sokolow

    2 жыл бұрын

    @Brilliant Design! Not sure, but the numbers will be spread out, very few jams.

  • Brilliant Design!

    Brilliant Design!

    2 жыл бұрын

    @Mike Sokolow So what you are saying, is that instead of Raspberry Pi, we may soon have Strawberry Jam supercomputer?

  • Madhusudan Jeurkar
    Madhusudan Jeurkar3 жыл бұрын

    Can you make an additional video to include non mechanical processes such as PVD and CVD?

  • Billabong
    Billabong2 ай бұрын

    I once had a 3500 word essay on the difference between precision and accuracy in college. There is a huge difference.

  • Max Idontwanna
    Max Idontwanna3 жыл бұрын

    9:17 Not sure if that is Harvard or the U of A optics lab.. but I made several parts on the U of A's lapping machine as well as several parts for the LSST telescope for AURA. Happy to have been a part of it.

  • Johnny Betancourt
    Johnny Betancourt11 ай бұрын

    How the hell do you know so much about flatness????? Incredible content.

  • Nerfornothin1
    Nerfornothin13 жыл бұрын

    This should be a required video to watch for mechanical engineering classes.

  • SuperDeinVadda


    3 жыл бұрын

    I kinda know 90% of the content already. So showing it would be highly appreciated but may not be as necessary as you think.

  • TheCroatianSensation


    3 жыл бұрын

    I've had a Metrology class as a Machinist that taught me about these topics, it's actually sad that this is not mandatory for a mech eng, this is why i always say a great Mechanical engineer is one who was a machinist first.

  • T0BBi94


    3 жыл бұрын

    Not so much for mechanical engineering classes as for material science classes

  • Tim Hallas

    Tim Hallas

    3 жыл бұрын

    This should be a required video to watch for flat earthers. They actually think the surface of the oceans are perfectly flat.

  • caveman
    caveman3 жыл бұрын

    It has always fascinated me. How did we come about making a straight object, a flat object, a round object, perfectly. At least one of my questions here is answered.

  • Bill Remington
    Bill Remington3 жыл бұрын

    This is the first video I watched and he immediately got a new subscriber. Absolutely phenomenal

  • Macca46
    Macca462 жыл бұрын

    I remember watching my Dad use a straight edge, a set of feeler gauges, a 4" angle grinder (with a varying grit sanding discs) and some heavy cut & polish to shave the warped head of an old Toyota we had as a "bush basher" when we were kids... that fix outlasted plenty of other parts!

  • Satsuma GT

    Satsuma GT

    Жыл бұрын

    Nice compression ratio

  • Jonathan Holliman
    Jonathan Holliman3 жыл бұрын

    As a carpenter, the struggle is real! When you're not the only worker on project, things can get out of whack so easily! People tend to add their own tolerances to things that is already are the maximum end of the tolerance.

  • Atticus Magnus
    Atticus Magnus10 ай бұрын

    I just retired after44 years in Aerospace Quality and Engineering. This is one of the best general explanations on this subject that I've ever seen. Great job !

  • Atticus Magnus

    Atticus Magnus

    2 ай бұрын

    @Sighs Internally They're called "Gauge Blocks" usually made of extremely hard steel for wear resistance (although ceramic blocks we're in favor for awhile), they are precision ground on opposing faces - with a surface and finish that is so fine that they are able to be "wrung" together and will "stick" to each other (as in the video). They have various uses in Manufacturing/Quality Assurance applications.

  • Sighs Internally

    Sighs Internally

    2 ай бұрын

    do you know what the things at 9:30 and 9:40 are called?

  • David Doll
    David Doll3 жыл бұрын

    Very interesting information. I was surprised to find out that very flat objects will stick to each other. Very cool.

  • René Jansen

    René Jansen

    Жыл бұрын

    It's the Van der Waals force.

  • Mark C

    Mark C

    2 жыл бұрын

    Could it be the Casimir effect? Microscope slides are packaged with a powder-like substance between them to keep them from bonding. Occasionally you find them stuck to each other permanently.

  • Paul Bednall

    Paul Bednall

    3 жыл бұрын

    Air pressure causes the objects to stick or rather the lack of air pressure between the surfaces does.

  • rabie4x4


    3 жыл бұрын

    And it's not "exactly" known what causes this.

  • SouthJerseySound


    3 жыл бұрын

    The first time I saw it in person I was blown away. Whats even crazier is you cant just pull them apart and need to twist them off.

  • rexsolomon
    rexsolomon3 жыл бұрын

    Learned more about the topic in minutes than I expected from a YT vid. Great work New Mind! Subscribed.

  • Rex Transformation
    Rex Transformation Жыл бұрын

    9:20 And I always thought it was because there's a vacuum between the two surfaces... In the workshop we have some Mitutoyo gauge blocks; when I use those needed I make sure they are clean before joining them, and am always amazed how they bond together, just like in the video. But I always thought it was, as said in the beginning, due to a small vacuum. In fact, if I try to join them NOT by sliding them together, they DON'T bond. But if I slide them like in the video, they do bond. So I do think it's due to vacuum as the sliding pushes away the air, creating a sealed surface. But I may be wrong. Any ideas?

  • retsaM innavoiG

    retsaM innavoiG

    2 ай бұрын

    I'd imagine it's a combination, basically if there isn't a vacuum than there will be a tiny layer of air atoms in between the surfaces preventing any of the bonding to take place. But then the vacuum also makes them harder to pull apart, so it's a combination of both effects.

  • rugerdave


    Жыл бұрын

    Just an FYI, The proper way to wring Jo blocks together is to clean the surfaces of both blocks by placing a sheet of clean white paper on a surface plate and rub the surface of the block against the paper until the paper is clean, which is the same method to clean the faces on a mic (mike). Then wipe the face of each Jo block on the inside of your clean forearm, then wring the blocks together. If it's not done this way, the Jo blocks will start to get microscopic scratches on them and throw the calibration off. Wiping it on your forearm applies a minuscule amount of skin oil for lubrication. It's not a vacuum, both blocks are dead flat.

  • Christopher Darwin
    Christopher Darwin Жыл бұрын

    Very cool video! Learned several new things I did not know and had forgotten.

  • Tatterz
    Tatterz3 жыл бұрын

    I think you got lapping wrong, or it might be another form of polishing that I know of. But I think lapping does not remove material but smudges it into all the divets and holes on the material. This is due to the microscopic hot spots created by the abrasive. So it's like making a clay dish and then smoothening it with a wet hand

  • TheJuicyBurger
    TheJuicyBurger2 жыл бұрын

    I thought that the primary force behind "wringing" was atmospheric air pressure. On the size of the gage blocks in the video this would be about 10lbs holding them together

  • Jf aamand
    Jf aamand3 жыл бұрын

    As a kid i was wondering about how the first perfectly flat object was made as in my logic that would require something else equally flat to shape or form that object and thereby creating a paradox. Then i learned that liquids are perfectly flat and also that there are many different methods to produce "flatness". And finally i learn that everything is relative and depends on reference frames and that you can not know everything about anything. There will always be uncertainty, thats the only thing we can really know for certain ;)

  • hunger993


    2 жыл бұрын

    look up the 3 plate method

  • Jared Kennedy

    Jared Kennedy

    3 жыл бұрын

    What, were you some kind of ultra nerd as a kid? I guess I wasn't the only one pondering odd questions.

  • Jf aamand

    Jf aamand

    3 жыл бұрын

    @VioletGiraffe I get your point but i feel some kind of astounded that you had to mention the earth is curving aka round... If Earth didnt rotate and was covered 100% with water AND gravity was evenly distributed along the entire surface, then it would be quiet close to being spherical no matter how many valleys and mountains it contained. (the moon would have to go at this point also) Liquids are shaped by gravity and surface tension to my knowledge so you cant really apply a shape to it. The "fact" you mention would be nice for others if you elaborated a bit on that part. I totally get it but other people might not

  • VioletGiraffe


    3 жыл бұрын

    Liquids are not flat, though, they're curved along the Earth's surface. Which in turn isn't a perfect sphere. Fun fact: if the Earth was a flat disc or rectangle, spilled liquid would still not form a flat surface :)

  • Matt D

    Matt D

    3 жыл бұрын

    Haha, yep. Even with optical methods there will be gravitational distortion so it's impossible to actually measure it as you can't get a true reference, only better and better approximations of it. But, once you get down to those lowest levels anyway, reality itself becomes kinda lumpy and not at all a thing where straight lines and such even have much meaning :p (like, what even is a flat surface? The atoms themselves have uneven electron field densities, like their shape undulates, so there is no flatness)

  • Interstellarsurfer
    Interstellarsurfer3 жыл бұрын

    PSA: most sheet glass in production is actually roller glass. It's *far* from flat, and can be distinguished by the distortions you see when you look at it far off perpendicular. It's *much* cheaper to produce, as it doesn't rely on an expensive liquid tin metal bath to level it. Edit: I love the technical knowledge you delivered, minor quibble aside. Subscribed. 😁👍

  • Bob Man

    Bob Man

    Жыл бұрын

    Are you the glass expert guy from squid game.

  • CJ Green
    CJ Green2 жыл бұрын

    I remember when I was 18 and I got my 1st job working in an engineering factory, I used to grind wedges for tank brakes. The machine was a huge Schindler grinder with a magnetic flatbed where I loaded and ground 50 wedges at a time, the tolerance of smoothness required was 2 microns. I went on to become a carpenter, then after 10 years I became a computer analyst programmer, after 20 years in IT I took a masters in teaching and I now teach young children. Definitely not a flat career :)

  • Tharaka Nuwan

    Tharaka Nuwan

    2 жыл бұрын

    And how did u do that ? That would be an interesting story to hear How a carpenter become Computer scientist

  • Robert Keyes
    Robert Keyes Жыл бұрын

    Are any laser techniques used for the creation of very flat surfaces? I've seen videos on liquid-jet laser cutting that show their ability to create very precise and accurate cuts, but without requisite flatness of the remaining face, the utility of the resulting part is significantly less.

  • Active Atom
    Active Atom3 жыл бұрын

    Nice video, as a machine shop we know flat, granite surface plates lapping plates and tables, the surface plates are calibrated to their flatness annually or simi-annually, the process to confirm and certify this flatness is amazing with very advanced measuring equipment, this testing is completed to confirm that it still is in the parameters of the specifications from the original manufacturing of this granite. Our precision machinery must make parts that comply to these granite surface plates so this is a lot of very plate material machining we must do daily. CMM and now laser measure also shared as CMM Scanning, that is as exciting as the touch probe CMM was when we first met one, we do not have a laser measure CMM, these two guys cannot wait to learn how that works for the little shop guys like us some day. Thank you for taking this understanding to a larger understanding. Lance & Patrick.

  • El Cuhhh
    El Cuhhh Жыл бұрын

    As a machinist, I approve this message.

  • Jan Drebes
    Jan Drebes3 жыл бұрын

    Thank you. This is my real job. You have present it very interesting and correct 😃👍

  • Jan Drebes

    Jan Drebes

    3 жыл бұрын

    @Victor Masson thank you very much that you think the same like me ☺️😃

  • Jan Drebes

    Jan Drebes

    3 жыл бұрын

    @Mathew Mabee I work for LEGO and make plastic injection molds. LEGO have pretty high standards. They only want the best. I make the mold inserts. I must reach tolerances of +-0.002 mm (I think that‘s +-0.0000787inch). I make it with japanese high speed cutting machines. I live in switzerland and I made an apprenticeship for four years by the company where I‘m employed. I earn now 25 CHF per hour that‘s 25 $. I live with my parents and have no car. That way I can save money.

  • ian trofimov

    ian trofimov

    3 жыл бұрын

    Pretty sad I get $42 without any formal education

  • Linus Teir

    Linus Teir

    3 жыл бұрын

    @Josh Worthley curb your expectations, i maker under 16$ an hour with an BA at an NMI

  • Scientist Walter

    Scientist Walter

    3 жыл бұрын

    Thanks for making flat stuff

  • Chazz7555
    Chazz75553 жыл бұрын

    Such a good practical channel 👌

  • iTeerRex
    iTeerRex3 жыл бұрын

    Just found the channel.. Great content! Thank you! btw You didn't mention how the reference flat surface is made flat to begin with.

  • TJ Knapp
    TJ Knapp Жыл бұрын

    As a mechanical engineer and cmm engineer at an aerospace company is makes me so happy to watch this.

  • JonathanH13
    JonathanH133 жыл бұрын

    Excellent. Extremely comprehensive video!

  • scottsutoob
    scottsutoob Жыл бұрын

    My roommate was an R&D machinist. One of his jobs was making things very flat for the semiconductor industry.

  • Strothy2
    Strothy23 жыл бұрын

    you sir just earned a new subscriber, I myself work in machining, flat really in most cases means I'm within +-0.01mm :D If you go over to the optics side they measure flatness in radiuses the size of the planet :)

  • Bryan Martinez

    Bryan Martinez

    3 жыл бұрын

    I just imagine you going to 0.02 and chuck whatever your making across the shop.

  • aboriani


    3 жыл бұрын

    Strothy2 and by radiuses of the size of the planet, you mean infinitely large radiuses, cause the earth is flat, everyone know that. And before anyone takes me seriously, yes, I am joking

  • Gen. Buck Turgidson
    Gen. Buck Turgidson3 жыл бұрын

    I just watched the video on tolerances and immediately searched for the title The Science of Flatness and behold! here it is! great video! can you do a video on navigating a spherical object? I was in the navy and always wondered how to keep a straight bearing near the poles.

  • Joshua Bowerman
    Joshua Bowerman3 жыл бұрын

    How do you not have more subscribers? your videos are amazing!

  • New Mind

    New Mind

    3 жыл бұрын

    Thanks, the channel is only a year old, it’s growing rapidly.

  • London Jordan
    London Jordan2 жыл бұрын

    Nice work. Very informative.