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  1. #1
    Mustafa Umut Sarac's Avatar
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    Lens Grinder on rail + no cnc + for diy men

    I am researching for diy lens grinding . This paragraph is somehow technical and forcing the limits of my english.
    As I told at my previous mails and as agx points , lathing is a way for lens grinding.
    I am meaning with lathing , a motor is turning with the glass piece and a norrow grinding head is drawing the shape of the lens in 2 dimension on the glass piece and removing the material.
    I am a person who wants to manufacture many same lenses for diy camera for example lomo anamorphic lens copy.
    I will be needed to carve may be 6 surfaces with high precision.
    I have a solution IF you have similar needs , and if cnc electronics , controllers and motors seem to you very expensive.
    I think grinding turning head could be built to move on interchangable rails to move for grinding the glass.
    These rails could be built relative cheaply at cnc shops one time but can be used hundreds times.
    CNC machines work 1/1000 mm precision but even a leica apochromatic lens element have a 1/125 mm precision. That is a important point or barrier , you can cross it on rails.

    Best ,

    Mustafa Umut Sarac
    c copyright

  2. #2
    Mustafa Umut Sarac's Avatar
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    may be laser cut titanium spacers can be used as tooling guide

  3. #3
    AgX
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    So instead of having the lens grinded on a CNC-lathe in a specialised workshop, you intend to use a manual lathe of your own, attach some custom made sort of rails and replace the standard perpendicular movement of the tool by a movement of the tool on these rails instead?
    (I guess the proper term for these rails would be `cammed guides´ or something like that.)

    Concerning the precision of a lathe, as far as I know a common statement is the perpendicular deviation of the turning axle. I this involves an angular movement the error will be greater at the perimeter to be turned at its perimeter in axial direction.

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    Have you checked to astronomy sites?
    It's not the camera......

  5. #5
    Mustafa Umut Sarac's Avatar
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    I am checking everything but it does not mean i m remembering or understanding everything. There are commercial grinders outside , like using magnetic or chemical liquids , or using diamond coated turning circle as the grinder or cnc lathes or negative spherical iron lens molds which shapes the turning glass with liquid barrier.
    I think my method is easier if you use laser cut spacers as guide , for example.
    If you lost one part or if you have customers who want from your lens design , you can produce it with your interchangable spacers , i think.

    best ,

    mustafa umut sarac

  6. #6
    Mustafa Umut Sarac's Avatar
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    AgX , do cnc shops grind lens ?

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    Quote Originally Posted by Mustafa Umut Sarac View Post
    AgX , do cnc shops grind lens ?
    I would not think so, as the abrasives used (link: http://www.covington-engineering.com/grits.htm) would damage CNC machines requiring a very costly rebuilding.
    It's not the camera......

  8. #8

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    freygr, what Mustafa suggests seems very impractical. But and however, patents have been issued for turning lens elements on a lathe using a diamond bit. No grit is involved.

  9. #9
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    I have seen a video of machining contact lens blanks made from hydrophilic plastic. I forget whether or not they were finish polished using abrasives. Glass and other mineral crystalline materials used for lenses would be very difficult or impossible to produce this way. I think Mustafa should acquaint himself with traditional lens grinding techniques. If there was a better way they would be doing it.
    Richard

    Why are there no speaker jacks on a stereo camera?

  10. #10
    AgX
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    Dan,

    Whether one uses a diamond (scraping?) or a carbide grinding tool, the whole procedure will make a mess. Something which could be taken care of with a custom lathe, but sure means asking for trouble at a standard cnc-workshop.

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