How to make Very Flat Optical Surfaces on Glass

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  • Опубліковано 22 гру 2024

КОМЕНТАРІ • 495

  • @mccallan2798
    @mccallan2798 3 роки тому +645

    I've got absolutely no idea why this video was recommended but I'm so glad it was.
    Fascinating. Well done.

    • @robotslug
      @robotslug 3 роки тому +6

      Same

    • @thekeyfox
      @thekeyfox 3 роки тому +5

      Same

    • @BootyYeeter
      @BootyYeeter 3 роки тому +3

      Same

    • @88njtrigg88
      @88njtrigg88 3 роки тому +5

      It's because your subliminally interested in light & optics.

    • @mcpozzm6321
      @mcpozzm6321 3 роки тому +2

      It started when I clicked on a bartender showing how to make optically clear ice cubes for drinks, next day this was in my feed.

  • @TheWtfnonamez
    @TheWtfnonamez 3 роки тому +454

    Totally counterintuitive. I've done a fair bit of metalwork sanding and polishing, so I naturally assumed that optical polishing would be similar, only using something harder and flatter to grind the surface. It never occurred to me that the rotational grinding process would use something ductile, yet get better results. Thank you very much for the excellent explanation.

    • @stanrogers5613
      @stanrogers5613 3 роки тому +37

      In metalworking terms, it would be very similar to using an aluminum, copper, or tin lap (as in watchmaker's "black polishing"). You want your lap to be softer than the material to be cut. Your lap becomes a matrix to hold the abrasive particles in place, and the cutting happens on the material that can't just grab and hold the abrasive. (Tin, by the way, gives absolutely amazing results when polishing steel. It's just _really_ stringy to machine when you're initially making the lap. Save it for your finest - sub-micron - grits.)

    • @stc2828
      @stc2828 3 роки тому +13

      You polish silverware with fine cloth which is softer than silver. If you use sandpaper the result would be terrible.

    • @gvidas1338
      @gvidas1338 3 роки тому +2

      Very informative yet old video on lapping metal parts by rotation. Check this: ua-cam.com/video/fnoVV-RWIWY/v-deo.html It vey clearly explains "how it's made".

    • @sakelaine2953
      @sakelaine2953 3 роки тому +1

      @@gvidas1338 This is great, thanks!

    • @matter9
      @matter9 3 роки тому +5

      I feel there’s a general misconception when it comes to lapping a polishing that is a result of focusing on the lap material. As the first comment responder noted the lap only hold the cutting media. There are three fundamental rules for cutting to occur, though I only usually remember two. The important one here is that the cutting “tool” (in this case lapping or polishing compound) MUST be harder that the workpiece. The second is that there must be relative motion. The third escapes me.
      But in either case it is not the lap that cuts the work piece but the embedded abrasive. Apologies for the lecture comment but lapping and polishing seem to be no different fundamentally than any other metal removal process; hard removes soft.
      In the case of polishing silverware presumably there is some residual polishing compound on the cloth that is the effective mechanism for removing the oxide layer.
      Also, if I’m glaringly wrong please correct me. 👍
      Edited for autocorrect errors.

  • @hydrocarbon82
    @hydrocarbon82 4 роки тому +158

    Flat-out the best vid on making flat optical surfaces! Clearly thought out well, I couldn't pitch in any criticism. It's almost like we're on the same wavelength.

    • @digitalradiohacker
      @digitalradiohacker 3 роки тому +13

      What a cheerfully bright comment! I for one found the video very illuminating, and it seemed to polish out all the rough spots in my dull and hazy knowledge. You could say that it expanded my bandwidth....

    • @yashsvidixit7169
      @yashsvidixit7169 3 роки тому +6

      @@digitalradiohacker makes me wanna leave my daily grind and do something else

    • @bellowphone
      @bellowphone 3 роки тому +5

      Micronically inquisitive mind lapped up the precision explanations.

    • @Asdayasman
      @Asdayasman 3 роки тому

      If y'all don't cease with immediacy I'm gonna jump into a woodchipper.

    • @DocBree13
      @DocBree13 3 роки тому

      😂

  • @noanyobiseniss7462
    @noanyobiseniss7462 2 роки тому +17

    The true test of whether someone has mastered a field is their ability to explain it to the uninitiated in a clear and concise manner, you sir are a credit to the field.

  • @frog8220
    @frog8220 3 роки тому +53

    How did I end up watching 12min of "how to polish something to the nm scale?" But you explained it so well that I understood it without any previous experience in polishing glass or anything for that matter

    • @Kargoneth
      @Kargoneth 9 місяців тому +1

      It's rather hypnotic.

  • @TickyTack23
    @TickyTack23 3 роки тому +60

    This is really good, so well detailed. It seems over the years there has been a lot of demonstrations of optical grinding/lapping, lots of "recipes" so to speak, without any detailed explanation as to why it works. I'm coming out of this with a deeper understanding of the process, only took 12 years, but better late than never!

  • @tombesson7293
    @tombesson7293 3 роки тому +279

    This video reminds me of the optician who fell into a lens grinder and made a spectacle of himself.

    • @MikeWiggins1235711
      @MikeWiggins1235711 3 роки тому +71

      That's not as bad as the glass blower who accidentally inhaled and now has a pane in his chest.

    • @yashsvidixit7169
      @yashsvidixit7169 3 роки тому +51

      @@MikeWiggins1235711 Still not as bad as that chef who, while cooking some some chicken broth, fell into the pot and made a laughing stock of himself.

    • @Cynthia_Cantrell
      @Cynthia_Cantrell 3 роки тому +7

      Clearly, I didn't see that coming.

    • @tombesson7293
      @tombesson7293 3 роки тому +35

      @@Cynthia_Cantrell Did you hear about the guy who wondered why the baseball kept getting bigger and bigger, then it hit him.

    • @user-hv6wb5gk8p
      @user-hv6wb5gk8p 3 роки тому +14

      Reminds me of the lab technician who spilled some acid on himself. Really left him fuming.

  • @martinthemillwright
    @martinthemillwright 3 роки тому +5

    One of the most clearly explained process ever seen on UA-cam. Beautiful. I feel like building one of these now.

  • @Dukey8668
    @Dukey8668 5 років тому +75

    I have been interested in optical engineering for a long time now and yours is the first channel I have seen that covers it well. So thank you for making such excellent videos.

  • @kochipj
    @kochipj 3 роки тому +4

    I work in the optics industry for a couple of years now and I have to say that your channel is a real treasure! Your videos are both, highly educational and entertaining. Keep up the outstanding work!

  • @shripadwarudkar6487
    @shripadwarudkar6487 3 роки тому +1

    Hats off to your narration... I simply was thrilled. I am a retired engineer, 73 yrs.

  • @TungstenCarbideTempe
    @TungstenCarbideTempe 3 роки тому +6

    The principle looks simple, its just a tar and turntable, but those who tried working with glass, especially polishing and making it precise, knows that its extremely hard, takes years of practice and patience. Great video.

  • @tomtang2639
    @tomtang2639 3 роки тому +27

    jeez why didnt youtube algorithm recommend this to me earlier??? Its fascinating!!

  • @stickyfox
    @stickyfox 3 роки тому +48

    I used a machine like this in the 90s to flatten hydraulic motor parts. Instead of pitch, the wheel surface was steel, and the surface was kept flat by adjusting three rings which also kept the parts in position on the wheel. We'd check it a couple times a day by washing the abrasive off and placing an optical flat on the wheel. But other than that it worked the same way.

    • @hindugoat2302
      @hindugoat2302 3 роки тому +4

      its not the same as true level

    • @stickyfox
      @stickyfox 3 роки тому +8

      @@hindugoat2302 Reality is poison! I can't live like this!

    • @stickyfox
      @stickyfox 3 роки тому +1

      @Andrew Crews I worked on Eaton and Sauer-Sundstrand axial piston pumps and motors. We would replace pistons and cylinder blocks and send them out to be resleeved/refinished.

    • @michaelmello42
      @michaelmello42 3 роки тому +2

      I appreciate this comment very much after having done very similar work in the 90s. I used to test lapped and partially polished parts with an optical flat to infer the concavity of the part (convex or concave). Once the concavity was determined, I inferred the lapping wheel's (opposite) concavity and would adjust the rings' position to correct the wheel.

    • @subhashkulkarni1117
      @subhashkulkarni1117 8 місяців тому

      Pl.explain the process in detail

  • @MaxRomantschuk
    @MaxRomantschuk 3 роки тому +4

    This is the most satisfying and informative presentation I've seen in ages. As a photographer I really appreciate the craftsmanship required to produce high quality optics. My hat off to you Sir! 🎩

  • @zekeroche7915
    @zekeroche7915 2 роки тому +1

    I've been polishing for a year now. This was super informative. Putting images to techniques helps me understand more of what I do all day long lol

  • @Dak3
    @Dak3 3 роки тому +19

    Using interferometric fringes to test optics, what an ingenious setup!

    • @kellymoses8566
      @kellymoses8566 3 роки тому +3

      If you think that is impressive the Laser Interferometer Gravitational-Wave Observatory uses interferometry to detect changes in length less than a 10 thousandth of the diameter of a proton.

    • @BarneyDesmond
      @BarneyDesmond 3 роки тому +1

      @@kellymoses8566 luckily we don't need *quite* such precision for optics :)

  • @richardlee9685
    @richardlee9685 3 роки тому +23

    When you shut the machine down overnight, is it necessary to maintain the lab at a cool temperature to minimize pitch movement?

    • @shannonpincombe8485
      @shannonpincombe8485 3 роки тому +18

      Nah...you just use auto tune. Everybody does these days. Hehehe

    • @tjsbbi
      @tjsbbi 3 роки тому +3

      @@shannonpincombe8485 That's how those T-pain sunglasses are made.

    • @juliusfucik4011
      @juliusfucik4011 3 роки тому +1

      I think there is a tradeoff. It would certainly help, but investing in climate control may not be worth it. Also, it seems heating the plate and then weighing it down removes enough deformity in a small amount of time.
      These techniques are fascinating.

    • @thedudeamongmengs2051
      @thedudeamongmengs2051 3 роки тому

      @@shannonpincombe8485 I respect the pun

    • @ai_university
      @ai_university 3 роки тому

      They run 24hrs

  • @ramkitty
    @ramkitty 3 роки тому +3

    Excellent vector drawing demonstrating the constant angular velocity.

  • @СергейХомяков-в7э
    @СергейХомяков-в7э 2 роки тому +2

    I have been polishing precision optics for 12 years, I really enjoyed the video, thank you. I do the final polishing of the optics on a spindle in a zerodur plate with holes, I put planes with weights in them, according to a similar principle. pitch polishing pad for the night I turn over on a plate smeared with Regipol with good flatness

  • @therealzilch
    @therealzilch 3 роки тому +12

    I've always thought there was something almost magical about being able to make incredibly accurate optical surfaces, flat or otherwise, with no precision tools whatsoever. I ground my 6" parabolic mirror by hand, and figured it to 1/20 wave accuracy on a pitch lap, with no references other than the Foucault test.
    Very nicely done. Subscribed.
    cheers from sunny Vienna, Scott

    • @robertmccabe8632
      @robertmccabe8632 3 роки тому

      if you like that; then the three plates to make a surface plate is another example of this principle (though wil hardish surfaces)

    • @therealzilch
      @therealzilch 2 роки тому

      @@robertmccabe8632 Indeed. I use this principle to keep my sharpening stones flat. Using silicon carbide abrasive, I grind A against B, B against C, and C against A.

  • @janpoppeliers8619
    @janpoppeliers8619 4 роки тому +3

    Very clear and detailed explanation, best I found so far (and no irritating background music).
    Cool how you built the turntable from a washing machine motor and rollerblade wheels!

  • @denisnikitin5894
    @denisnikitin5894 3 роки тому +18

    Thanks for the video, it's very informative. So the polishing table is an aluminum disk with a motor stator attached to it, and you press the pitch lap by using a granite plate, but I was wondering if you could share what the pitch lap substrate is made of? It looks like a few inches thick disk. Is it also granite?

    • @HuygensOptics
      @HuygensOptics  3 роки тому +13

      No actually in this particular case it is borosilicate, which has a thermal expansion coefficient that is about 3 times lower than granite (which is an advantage). You can however use granite without problems if you have good temperature control.

  • @MimicGriphon
    @MimicGriphon 3 роки тому +3

    Am I the only one that loves this type of stuff, but at the same time, completely understands how boring most people probably would find it?

  • @jlmknight
    @jlmknight 3 роки тому +2

    Very fascinating seeing someone so specialized and advanced in their field, thank you for sharing.

  • @SqueakerT
    @SqueakerT 3 роки тому +1

    At work here in Germany they got mad at me for filing like this....that you work in nm tolerances and do so as well made me really happy. The understanding of why one would do it so they just couldn’t understand. Also an amazing video, very informative. Keep up the good work!

  • @maxenielsen
    @maxenielsen 3 місяці тому +1

    Excellent explanation! I’ve been aware of over-arm polishers for lenses, but not aware of this method. You openly share a lot of which others would consider trade secrets. Even so, I have to believe that if I were to set up a similar polishing system, using everything you show here, I probably wouldn’t get results as good. Thank you!

  • @adrianrevill7686
    @adrianrevill7686 3 роки тому +6

    Thank you, i always wanted to know how it was done. Very clear description.

  • @davejenkins8524
    @davejenkins8524 3 роки тому

    I have always wanted to see Mach 3 used in a unique way like this. BRAVO !

  • @williamcashion5262
    @williamcashion5262 Рік тому +1

    It's hard for me to believe but, I lapped and polished for 20 years (Gator Diamond, Inc) and didn't know half of this info. Thanks, Bill

  • @satankarmukesh3552
    @satankarmukesh3552 5 місяців тому +1

    Thank you for nice video, will you please let me know how to make single 40 to 80mm discs flate up to 1/6 wave or 50 nanometre regards.

  • @movax20h
    @movax20h 5 років тому +6

    Fascinating videos, with plenty of details. Thank you for all this useful info and diagrams!

  • @mdevidograndpacificlumbera1539
    @mdevidograndpacificlumbera1539 3 роки тому +5

    Do you always use the same grit to polish? If not, do the grits find themselves trapped in the pitch? Do you have to use different pitch plates for each grit?

    • @HuFlungDung2
      @HuFlungDung2 2 роки тому

      Polishing is the final stage of producing an optical quality surface and there is only one compound used on a given lap.
      Grinding the surface to a desired rudimentary curve is called grinding, not lapping. Pitch laps do not grind but only polish. The amount of material you'd remove by polishing is miniscule and nobody wants to waste time doing any more polishing than necessary.
      Grinding a surface starts as a rough cut to quickly give a desired curvature and to remove casting irregularities. Then a succession of finer grits is used to remove the deep scratches left by the previous grit. This is done with a hard tool on the workpiece and an abrasive slurry is run onto the surface. It looks a lot like lapping with a pitch lap, but because the tool is hard, it can be reliably cleaned off when it is time to change to the next finer grit size.

  • @rapsod1911
    @rapsod1911 5 років тому +6

    This is very interesting. I read somewhere that for lapping of silicium wafers they use some chemicals instead of abrasive particles. I can't imagine how precise they must polish wafers for 4nm technology.

    • @HuygensOptics
      @HuygensOptics  5 років тому +23

      It's generally a combination of both. If you use a chemical that etches your surface while you are polishing, you can use a very mild (or soft) abrasive agent, which results in a smoother result. By the way, when you use Cerium Oxide to polish glass, chemical interaction also helps speed up the polishing process. For wafers the actual flatness is less important that the smoothness, since modern wafer steppers make a heigh map of the wafer to correct for the total thickness variation when clamping a wafer to the chuck. Modern technology wafers are indeed incredibly smooth and flat (from the dimension of individual components to that of the full chip)

  • @PronatorTendon
    @PronatorTendon 3 роки тому

    I wasn't aware how much I like this content

  • @TheEvertw
    @TheEvertw 3 роки тому

    Prachtig werk! Ik heb me altijd al afgevraagd hoe die dingen zo vlak konden worden gemaakt.

  • @turbocpt1
    @turbocpt1 3 роки тому

    The explanations you give is perfect. Even a brick can understand this.

  • @MindbodyMedic
    @MindbodyMedic 2 роки тому +1

    this filled in some gaps in my knowledge, really great stuff.

  • @asdf35750
    @asdf35750 3 роки тому +3

    Using a Fisher and Paykel motor driven by a VFD is genius! So much simpler than the old belt and pulley reduction.

  • @royalgilpin4922
    @royalgilpin4922 2 роки тому +1

    This video reminds me of how profound our technological advancement has been. Just think of how many different people had to cooperate and dedicate basically their entire lives to engineering better solutions in the relatively niche field of precision optics. Using a high viscosity fluid as a lapping surface? How the hell did anybody come up with that? Stuff like this just blows my mind.

  • @gkelly
    @gkelly 3 роки тому

    I would have never guessed that you'd use a malleable disc to do the polishing. Really fascinating to see how this is performed, thanks for the video!

  • @tottedpotato
    @tottedpotato 3 роки тому +2

    Hello youtube algorithm...thank you for suggesting something I didn't know i needed to know

  • @chris-hayes
    @chris-hayes 3 роки тому +1

    No idea why this is in my recommended, but very interesting. I'm amazed this kind of thing can be DIY with the proper knowledge and materials.
    I would consider myself a maker more in the software area, it's always cool to see what other people are working on. Keep making!

    • @Bill.Pearson
      @Bill.Pearson 3 роки тому

      "proper knowledge and materials"--including an old washing machine motor and rollerblade wheels.

  • @aerosoapbreeze264
    @aerosoapbreeze264 3 роки тому +1

    Your channel deserves more subscribers

  • @matter9
    @matter9 3 роки тому +3

    Excellent. Very happy I found your channel. Honestly, as a nerd in training, a good friday night for me includes such terms as nanometer and interferometry. Looking forward to your next video!
    Edit: trainings -> training

  • @Cjerbasko
    @Cjerbasko 3 роки тому

    Thank you kind algorithm for bringing me here. This was very interesting.

  • @lschmidt2405
    @lschmidt2405 3 роки тому +1

    When the pitch drapes off the sides, how do you get it back up on top? Do all the different grade abrasives get mixed into the tar? Do you then have to replace the tar? How do you setup for lens grinding as opposed to flats? How are multifocal optical lenses ground? eg for spectacled?

    • @ccaissie113
      @ccaissie113 Рік тому

      freeze then chip it off and melt and recast. the polishing compound is micon sized...not grit. used to use rouge, but there are better compounds not so messy.

  • @BruceSchaller
    @BruceSchaller 3 роки тому

    This is an excellent way to do low speed control with a VFD. Thank you for the good idea.

  • @RobertMilesAI
    @RobertMilesAI Рік тому

    Does this type of pitch polishing give you any assurances of the parts being square or parallel? I imagine you might often want an object with two opposite faces both very flat and very parallel to each other, but my totally uninformed intuition says this process might not be able to give you that?

    • @HuygensOptics
      @HuygensOptics  Рік тому +1

      That is correct. To create parallel surfaces, generally two-sided grinders and polishers are used that have two abrasive disks spinning in opposite direction while applying pressure.

  • @fearlessjoebanzai
    @fearlessjoebanzai 3 роки тому +2

    I can't shake the feeling that I'm learning knowledge that I will never need to use!

    • @Bill.Pearson
      @Bill.Pearson 3 роки тому

      Agreed. Like watching This Old Tony.

  • @raguaviva
    @raguaviva 3 роки тому +5

    physicist here, every single video of yours is mesmerizing, I have no words!

  • @Crobisaur
    @Crobisaur 3 роки тому

    Your videos constantly inspire me to want to build my own lenses for different optical projects. Thank you for sharing your designs and knowledge!

  • @DavidG2P
    @DavidG2P 3 роки тому

    What a fascinating microscopic world lies behind these seemingly primitive (to the layman only, of course) machines!

  • @T____K
    @T____K 3 місяці тому +1

    well explained, no questions, sir! great video

  • @youcancallmeque
    @youcancallmeque 3 роки тому +1

    i have no idea why UA-cam recommend me this video. What more fascinating
    is i watched it until end, and still have no idea what is that.

  • @W1ldTangent
    @W1ldTangent 3 роки тому

    The algorithm sends me to strange places sometimes, but it sure can be a fascinating journey. Today I learned something I did not know yesterday, thanks.

  • @beaudanner
    @beaudanner 3 роки тому

    So fascinating the science and math that goes into allowing us to achieve this. I would have never guessed it was pitch

  • @marklimbrick
    @marklimbrick Рік тому

    Last minute had the information I didn't know I needed. Blocking pitch does put pressure on glass held to a backing. All the old film of spectacles and camera lenses show blocking, but these are not expected to be accurate to fractions of a wavelength. OK now I will also avoid lots of messy cleaning up as well.

  • @bekanav
    @bekanav 4 роки тому +2

    Very good stuff. I've done my share of glass pushing, long long hours of manual work. I tried to make 200mm flats but I constantly got into troubles in 1um (two rings) level... Perhaps I return to them sometimes, even though I hardly remember why I started making them LOL (ok it was some cassegrain telescope idea, and another for testing other flats)

  • @MegaFrankels
    @MegaFrankels 3 роки тому +1

    When you go through the grits of silicon carbide or cerium oxide, dou you change pitch plates or clean it very well? How do you make sure some coarse grit doesnt ruin the later polishing steps?

    • @HuygensOptics
      @HuygensOptics  3 роки тому

      The silicon carbide grinding is not done against pitch but against other glass or granite plates. You have to carefully clean and rinse between grains (not only the plates, the work space, but also your hands) in order to avoid contamination.

  • @fhgx32
    @fhgx32 3 роки тому +1

    Very good explanations with great schematics. Great video overall.

  • @elischultes6587
    @elischultes6587 3 роки тому

    This gave me a moment of connectivity to my Grandad. He ground rifle scope glass for a few years. Now that’s not flat but more of polishing

  • @somewherenear3003
    @somewherenear3003 3 роки тому

    Today this was recommended to me and I watched till the end

  • @lrakschmidt2880
    @lrakschmidt2880 3 роки тому +1

    I'm wondering if you can put the pitch lap in the freezer when not in use for weeks or months?

    • @HuygensOptics
      @HuygensOptics  3 роки тому +2

      Sure, that is the way to store them over longer times. It also avoids the evaporation of the more volatile components from the pitch so it keeps the right viscosity. However, even then you have to put some effort in bringing them back in a usable state, because, they will loose shape on the sub-micron scale.

  • @perspectivex
    @perspectivex 4 роки тому +2

    Like the other people have said, really great video and clear explanation. One question: What's the relation between the maximum size of flat you can grind vs. the minimum size of the large pitch plate below? I mean, how small can you make this machine vs. how big of a flat can then be produced. I am wondering about grinding flat mirrors for star diagonals for telescopes, not sure how big yet but maybe up to 90mm (?).

    • @HuygensOptics
      @HuygensOptics  4 роки тому +1

      If you have a round mirror the size can be up to 35-40 percent of the pitch ring. However it is more difficult for rectangular objects like star diagonals. You need to contain them in a ring. For a 90mm diagonal you need at least a 350-400 mm pitch ring. Also you cannot attach this type of object at the angled surfaces to the holder, but only at surfaces perpendicular to the pitch surface. For example using hot glue. If you look carefully at the connection of the elliptical mirror at 6:58 in the video you see that it is connected at the short side with two dots of hot glue (on each side) to the aluminum holder.

    • @perspectivex
      @perspectivex 4 роки тому

      @@HuygensOptics Could you just create the flat in whatever shape is most convenient for the machine then water jet cut it out or something like that to get your desired shape (ellipse, rectangle, etc.)?

    • @HuygensOptics
      @HuygensOptics  4 роки тому +1

      It's possible, but it depends on the flatness you require. Generally the cutting will introduce stress/cracks in the material at the cutting interface, which can seriously deform the objects in the um scale range. If you require high quality optics it's not an option. Also the abbrasives in water jet cutting can very easily damage your optical surfaces, even with protective layers applied.

    • @perspectivex
      @perspectivex 4 роки тому

      @@HuygensOptics hm... maybe you could use the larger blank of 'convenient shape' and cut out the desired part(s) about 99% of the way with a small diamond grinding bit of some kind, leaving a holding ring or maybe tabs, then do the flatness grinding/polishing, then just snap the parts out by breaking the thin retaining glass. Or maybe try EDM using one of the techniques for non-conductive materials. But, yeah, at that point there's probably not really an overall cost/effort savings. :)

    • @HuygensOptics
      @HuygensOptics  4 роки тому +1

      That is a trick used with for example with the central hole in telescope mirrors: you drill almost completely through except fort the last 2mm or so. My personal experience with this method is not positive. Generally, if there is residual stress in the material, it will be partly released when cutting parts out, deforming the piece. I always bring the object in its final shape and then start grinding and polishing and focus my efforts on a good mounting method and the correct tool shape.

  • @Sirmellowman
    @Sirmellowman 3 роки тому +1

    is this similar to how they make the large telescope mirrors?

  • @josephhertzberg2734
    @josephhertzberg2734 3 роки тому +1

    I had no idea about any of this. Fascinating.

  • @Santibag
    @Santibag 10 місяців тому +1

    The closest thing I do is knife sharpening, but I always wondered about stuff like straightness, flatness, and smoothness. This videos was very interesting.

  • @htchtc203
    @htchtc203 2 місяці тому

    Thanks you, Sir. Very good explanation of optical polisher.

  • @AssmannVerspaning
    @AssmannVerspaning 4 роки тому +1

    So-de-knetter... té gek dit! Leppen van metalen onderdelen doe ik met veel liefde. Leppen met pek is iets wat ik nog nooit gezien heb. Dus: fantastisch om nu met je neus zowat óp de lepschijf te zitten. Met commentaar van een kenner. Hartelijk dank!! Ik kijk erg uit naar de video over de vlakheidsmeting! Groeten - Nobby Assmann

  • @jacob_90s
    @jacob_90s 5 місяців тому

    10:00 So not necessarily, and not usually to that degree. Yes, surface plates do have stricter requirements for local flatness vs overall flatness.
    For instance a grade AA surface plate of 18x18 in, has an overall flatness requrement of 50uin, but a local flatness requirement of only 35uin, so that would definitely need to be checked for whatever specific surface plate you're using.

  • @gamemeister27
    @gamemeister27 4 роки тому +5

    If pitch is a liquid, couldn't flatness be achieved without a reference flat (like the bruiser or surface plate)?
    Enclose the pitch in a container with walls higher than it and heat it up enough to reduce the viscosity so it flows fast enough for the surface to find its level in a reasonable amount of time, then let it cool down. Surface tension would mess with the flatness near the walls, but closer in should be fine.
    I suppose you lose the grooves though, darn.

    • @HuygensOptics
      @HuygensOptics  4 роки тому +7

      You will have to wait for a long time before the surface reaches submicron flatness. Keep in mind that there is a volume contraction during cooling down. And of course it is not just about getting the tool flat, but keep it flat during processing.

  • @MajSolo
    @MajSolo 2 роки тому

    good to see that physics works
    all engineers experience the same when going down to nanometers
    no matter what kind of engineering they are doing
    and that is that solid material is moving ( slowly )

  • @SF-fb6lv
    @SF-fb6lv 3 роки тому +1

    Great video. Very very well explained! Brings back memories. I used to make achromats from blanks of optical class at home in high school for telescopes.

  • @ОливерКарески
    @ОливерКарески 3 роки тому +1

    Can a copper disc be very flat polished?

  • @1NicholasWeir
    @1NicholasWeir 4 роки тому +2

    Thank you for making and sharing this video! Great content and very informative!

  • @delon7282
    @delon7282 Рік тому

    Love the videos! I have a couple of questions:
    - what pitch specifically do you use in Jerome’s Pitch Polisher?
    - when setting up the pitch polisher, how do you ensure identical angular rotation of object and pitch lap? Are dimensions important or does the design itself ‘handle’ it?
    Thanks!

  • @bennylloyd-willner9667
    @bennylloyd-willner9667 3 роки тому

    Great video, Christiaan would be proud if he was here today!

  • @machinetoolswarehouse
    @machinetoolswarehouse 3 роки тому +2

    Awesome work! I am going to try this...

  • @RFC-3514
    @RFC-3514 3 роки тому

    10:07 - Well, in that image, the variation is actually 1μm over 200 mm (because it's between the centre and the edge), not 400, but I guess it won't always be such a continuous curve.

  • @jenna-leewessels7139
    @jenna-leewessels7139 Рік тому

    Good day sir...great video...just curious if you can lap any material on it..for example carbon and silicon and tungsten like seal face materials?

  • @HS-hz4fx
    @HS-hz4fx 3 роки тому +1

    Can glass be used as a sureface plate ?

  • @nawtdavids
    @nawtdavids 3 роки тому +1

    Really well made video! Great job.

  • @stoneybologna1982
    @stoneybologna1982 3 роки тому

    I'm an optical fiber telecommunications technician. We used to have to polish the end faces of our connectors when terminating them. 3 different ratings of polish paper and polishing in a " figure 8" motion. It was tedious. Faster speeds and the need for lower reflection at the connections has us using fusion splicing and factory terminated connections, now. No one misses " puck and polish" terminations.

  • @SuperAWaC
    @SuperAWaC 5 років тому +2

    i am a machinist by trade and when i was initially linked this video, and i only saw the title, i thought "oh great some charlatan is going to talk about taping sandpaper to a piece of float glass" but i was pleasantly surprised to see that was not the case and this is the real deal. subscribed.
    have you considered trying a cast iron master surface for the weight? as long as the room is at least loosely climate controlled, you could theoretically have a more economical option for a even flatter surface than the granite plate

    • @HuygensOptics
      @HuygensOptics  5 років тому +1

      In principle cast iron would work just as well as granite. The CTE is around 10-11 ppm, so compared with granite (8ppm) this is only slightly higher. And because of it's higher thermal conductivy, it will get to thermal equilibrium (and retain it's original shape) quicker than granite. So it would in fact be a better choice as a material. However, don't know how easy it is to make a cast iron disk of 400mm in diameter with a flatness of approx 1um. By the way, granite is not an expensive material.

    • @SuperAWaC
      @SuperAWaC 5 років тому +1

      @@HuygensOptics i know that in metrology cast iron is preferred for master surfaces, because it is more dimensionally stable and easier to make very (beyond AA grade) flat. for your specific use, it would also help as cast iron is denser so it would be heavier for the same size. that is why it came to mind.

    • @movax20h
      @movax20h 5 років тому +2

      @@SuperAWaC Actually in some super accurate machines, aluminium with internal cooling channels can be preferred too. This is because aluminium has way higher thermal conductivity (about 3 times higher than iron) and can be stabilized better, down to 0.1°C. Of course if you deal with big loads and need very high stiffness the cast iron or granite are preferred, but with low loads, aluminium counter intuitively can be even better. I can't find source and machines doing that right now, but I do remember seeing some year ago.

    • @CaskStrength777
      @CaskStrength777 4 роки тому

      I am a Tool & Die machinist and horologist and it made me happy to see there are other intelligent machinists watching things like this.
      I would second the use of a cast iron master plate. There is a guy who comes once a year to certify the multitude of granite surface plates we use in my shop and the man that does this is one of the rare ones who actually can re-lap the granite plates back into spec for flatness using a Master cast iron plate using aluminum oxide abrasives of various grades.
      Cast iron master laps are always made in pairs of three to get true flat reference surfaces- I know they are still made but I am not sure who you go to to buy one but if you had one I am certain you would get better results since they are what are used to correct even the granite surfaces

    • @SuperAWaC
      @SuperAWaC 4 роки тому

      @@movax20h I do know that many coordinate measuring machines have ways that are aluminum which is hard anodized and then lapped to extreme tolerances. It wouldn't surprise me if the very high end ones are also liquid cooled. I do know that they are kept in tightly temperature controlled environments with any heat sources removed (such as computers and humans) and put into different rooms, which is probably enough. But it would take longer for the whole machine to soak back to equilibrium if that environment were disturbed.

  • @brololler
    @brololler 3 роки тому

    how does this method compare to the three plate method - scraping three surfaces, two at a time ensures flatness with good tolerances.

  • @electroflow3721
    @electroflow3721 4 роки тому +2

    Dear Jeroen,
    Inspired by this video I settled out to try taking broken Nd:YAG crystals and polish them to be usable again. I have already hand-lapped then using 3µm abrasive to about 3 wavelength flatness. Currently, I am finishing building a pitch polisher following your example here to bring them to final flatness. However, since they are not glass I can't use cerium oxide. I found a paper suggesting using .3µm aluminium oxide. Do you have any recommendations for the concentration of abrasive in the slurry when using your type of polishing machine? and do you have a hint where I could source this polishing compound as a private person in small quantity for a reasonable price? (Using the keyword "Linde A" I found a lot of North American sellers but none of them seem to send to Europe where I am based)
    Thank you for your inspiring videos and in advance for any tips you can provide!

    • @vanaile9507
      @vanaile9507 3 роки тому

      Hi. I have the same your laser rod that need polishing aganst. Did you succeed?

  • @Dmitry_Golovanov
    @Dmitry_Golovanov 4 роки тому +1

    great!
    how to remove stress on the lens? large lens. after removing it from the block.

    • @HuygensOptics
      @HuygensOptics  4 роки тому +2

      it's the blocking itself that introduces mechanical stress in the material. After deblocking it is automatically removed again, but then the shape of the objects change, generally in an unpredictable way.

    • @Dmitry_Golovanov
      @Dmitry_Golovanov 4 роки тому

      @@HuygensOptics yes, that's exactly what I asked. after unblocking, the surface color changes unpredictably :-((
      instagram.com/p/CE9lp0yqDlC/?igshid=1tatmxrin9m51

    • @HuygensOptics
      @HuygensOptics  4 роки тому +2

      So, the only thing you can do here is keep blocking wax thickness as thin and uniform as possible. Also only block on flat surfaces. another option is to us pitch as a blocking substance, prefereably in a dot pattern. Next you give the pitch sufficient time (1-2 days) to relax, so that all stress flows out of the contact points between the two surfaces. This will reduce stress and deformation significantly.

  • @nuramd
    @nuramd 3 роки тому +5

    Today is the day i understood why tires have grooves

  • @Saki630
    @Saki630 3 роки тому +1

    its amazing how a bumpy surface can grind down to the nanometer range

    • @Asdayasman
      @Asdayasman 3 роки тому

      It's only bumpy on the macro scale.

  • @vladimirlevchenko1470
    @vladimirlevchenko1470 2 роки тому +1

    Hi. Огромное спасибо за ваш вклад в образование !

  • @johannglaser
    @johannglaser 3 роки тому +1

    Fascinating, and very well explained! Thanks a lot!

  • @fakestory1753
    @fakestory1753 3 роки тому

    This video made me happy.

  • @ValentinRusnac-q9b
    @ValentinRusnac-q9b Рік тому

    Great Video!!! Is there a way to make flat and parellel surfaces ?

  • @xXilisminusXx
    @xXilisminusXx 3 роки тому

    How does the bruiser plate get so flat? Also how can you assume that the bruiser plate tolerance is a shaped in a perfect arc?

  • @sandroac34
    @sandroac34 4 роки тому +1

    Hi, to make a "Economic bruiser" can I use a large granite disk with small disks of Soda Lime glass glued on face? Or best, can use a disk of thin sodalime glass (same size in diameter) glued on face of these granite disk? I can not pay for zerodur or fused silica... I´m changing a large 1,10 meter CG to CP... and the bruiser is my biggest concern... I purchase the book recommended by you, but doesn't suggest alternatives! thank you a lot.

    • @HuygensOptics
      @HuygensOptics  4 роки тому +1

      It is an option. Float glass and granite have approx. the same CTE (7-9 ppm/K) so that is good and I have actually done this in the past.The problem that you will encounter is changes in shape due to temperature changes and gradients. It will be very hard to get your process stable. So for example using a thick slice of Pyrex (CTE=3.3) has major advantages over granite. Pyrex blanks can sometimes be found for fairly low prices on Ebay.

    • @sandroac34
      @sandroac34 4 роки тому

      @@HuygensOptics Amazing... I have a pyrex blank 24" diameter end 1,5" thick and I can use that as a bruiser... You save my day again! Thanks! in few days I can put a video about this machine on my channel and invite you to see.

    • @HuygensOptics
      @HuygensOptics  4 роки тому +1

      @@sandroac34 looking forward to that!

  • @Viceroy_volz
    @Viceroy_volz 3 роки тому

    growing up in a machine shop makes me fascinated at what high precision milling can do. I'd take parts home and use the machined metal parts to play with.

  • @aniksamiurrahman6365
    @aniksamiurrahman6365 3 роки тому +1

    Yes, I have a question. How on earth you do these sorceries?

  • @ernestgalvan9037
    @ernestgalvan9037 3 роки тому

    Any links to making that motor (from washing machine and skate wheels)?

  • @bad_spider
    @bad_spider 3 роки тому

    hats down, top grade quality video, so rare