Time To Start A 3D 'Wants' List?

Discussion in 'Modelling' started by At Home Dad (Returning), Jul 28, 2011.

  1. At Home Dad (Returning)

    At Home Dad (Returning) Well-Known Member

  2. Mike L

    Mike L Very Senior Member

    Surprised the cost is only about £300!
    Must be for a pretty basic version. Wonder how much the 'consumables' eg print medium costs? More than printer ink I bet!
     
  3. At Home Dad (Returning)

    At Home Dad (Returning) Well-Known Member

    Whatever the cost, it means in effect that Von Poop
    can convert his Tiger owners manual into 3D designs
    and build all the individual parts to construct his own
    extremely accurate model... I could build my own Type
    XXI submarine for the back garden or have a lifesize
    Mosquito fighter bomber to put on the roof. In terms
    of what that means as a potential for museums etc
    regarding exhibits will be a great opportunity to show
    stuff which doesn't exist anymore

    The potentials are endless but it would also mean the
    end of airfix etc. perhaps they'll move over to selling
    3D plans of models rather than plastic models.

    The ability to print out a 1/72 Spitfire or whatever in a
    few hours is simply brilliant in my opinion. This is exactly
    why I avidly watched Tomorrow's World as a youngster -
    and it finally seems like some of the future stuff is here!!


    related links:

    3D printing - Wikipedia, the free encyclopedia

    http://www.reprap.org/wiki/Main_Page

    It’s a 3D World

    3D printing: The world's first printed plane - tech - 27 July 2011 - New Scientist
     
  4. RAFCommands

    RAFCommands Senior Member

    Way ahead of you on this.

    I'm using the Laser scan technique here to scan full size components of the Anson and Hurricane to produce 1:1 3D images to approx 0.2mm resolution.

    DAVID 3D Scanner

    Started with small items such as compass tray moving onto seat and now complete Merlin.

    Some post processing in Mesh Lab allows .dxf drawings that can be converted to traditional CAD/CAM numeric machining files for producing replicas.

    The step to 3D printing is possible for small items but my needs are metal to support transmitted stresses for the static example.

    Most recently I have been scanning several crash damaged identical components then "stitching" the un damaged portions together to reverse engineer an item that no drawings have survived of.

    Down load the trial David software and try out with a web cam and hand held line laser from your local builders merchant. Even in this basic form the results are outstanding.

    Regards
    Ross
     
  5. At Home Dad (Returning)

    At Home Dad (Returning) Well-Known Member

  6. Mike L

    Mike L Very Senior Member

    Ross, impressive stuff. I think I understood about half of that!
    Seriously though it looks like facilities such as this that used to be the realm of large industrial concerns are now becoming affordable to the masses, and what a boon to many hobbyists.
    Frightening to think what Adam (Von Poop) and some of the other members could knock up in their garden sheds soon.
     
  7. RAFCommands

    RAFCommands Senior Member

    Hi Mike,

    At the moment the plastic printing is quite limited because of the equipment and materials used.

    Best way to think of it is as a pixelated photo.

    The printer moves a x/y bed and puts a series of small blob of molten plastic in particular positions just like an old dot matrix printer printed a page. Only tweak for 3D is that the page is reset to the original start point and the print head raised by the height of the blobs and the page print repeated with a new pattern.

    This is repeated until all the layers forming the object are done.

    The limitations are:
    Plastic must be soft to allow molten flow and set quickly when heat removed.
    No right angle undercuts only 45 degrees (each layer can only increase in any direction by one blob).
    The object to be printed needs to be held in computer file in 3D format which needs quite extensive CAD drawing for even the simplest forms.

    OK for prototypes and visualisation but any object needs extensive hand finishing to get tactile results.

    The first two limitations can be overcome by using CNC cutters instead of the plastic printer and produce more durable items.

    The problem had always been creating the 3D file which was the labour intensive bit of 2D work that was then "lofted" to give height and 3D.

    The laser method uses the web camera to register a pattern on a 90 degree corner placed in front of it. The pattern is known so the David3D program can work out the parallax error of the camera and adjust the internal reference. It also knows the relationship between the circles so if you add a reference dimension the reference file is now scaled to the real world.

    Now add the object in front of the pattern and shine a laser line onto it but from about 40 degrees above the web camera. The laser line appears on the object. The software looks at the line on either side of the object and works out where all of the line would fall on the pattern if the object was not in the way. Next the software looks at the distortion of the line on the object and figures out how far from the pattern it is being reflected from giving a single contour of the laser line from the base pattern.

    Sweep the line down the object and you get a series of points forming a cloud that describe the object as a carbuncle on the reference plane. Finally the software subtracts the reference plane giving the point cloud for the object surface only.

    A complex surface with several undercuts will need laser illumination from above and below to show these areas.

    Turn the object through 45 or 90 degrees and repeat until all surfaces have been illuminated.

    You now have several massive file of points referenced to x/y/z that describe each face of your object.

    All this is simple geometry task. The next bit is the clever bit.

    You can load two adjacent face files and ask the software to check for points on the cloud that match then to align the faces together giving one face file that now has the two original faces meshed together.

    You continue with this until your object is now a single file of point clouds and all the faces are meshed together.

    Final action is to join the dots on the point cloud to form a surface mesh and this gives the 3D object.

    Sounds all very complex when written down but in reality with the David software it is "point and click" and a complex object can be scanned and transferred to a 3D file in only an hour of occasional human input.

    If you have a web camera and a DIY laser level line then download the trial 2.6 software from the David site. The calibration pages are a pdf file which you can print at any size. I used a room corner with the pages bluetacked on for the first go and got immediate results.

    Regards
    Ross
     
  8. At Home Dad (Returning)

    At Home Dad (Returning) Well-Known Member

  9. pauldawn

    pauldawn Senior Member

    i saw this being talked about on BBC in the early hours the day before yesterday. I must admit i was only half awake at the time, but what i got was that they were saying they can "print entire machines" - of any size and complexity?! forgive me if im ignorant, but how can you print out a machine? i assumed they meant the digrammes of machines ... but if this is the case, is it realy such a big deal? I actually thought they were saying they can now "actually print" a machine! even to the point they were raising the question as to how many jobs worldwide will be lost because of this technology. They were also saying they can print these 3d machines using a variety of print media including SUGAR!

    Now. im no techie type but how can you "print" a working machine using sugar, or any other material for that matter.?

    I know ive misunderstood something somewhere so id love someone to explain it to me.

    cheers

    paul
     
  10. RAFCommands

    RAFCommands Senior Member

    Paul,

    It's all about taking the next step from a 3D cad virtual model that resides only in the computer or displayed as a static snapshot from one viewpoint only.

    3D printing is the method where the CAD virtual model is transferred to the real world as an object that you can pickup, handle and join onto other parts.

    So in essence you need never have to stock or order a component again. When you need either part you call up the computer file, sent it to the printer then physically install the printed part into the assembly.

    At the moment the materials you can print are the limiting factor (powder, paper, thermoplastics or resin) but when the range is widened then you are into the realm of the Star Trek replicator i.e. everything can be created as a near finished product from raw materials without the need for any manufacturing/stockholder steps.

    The posts above go into greater details

    Regards
    Ross
     
  11. Gerard

    Gerard Seelow/Prora

    This is one of those ideas where Science fiction meets reality. Potentially all model manufacturers are now obsolete as are gaming companies if this takes off (pardon the pun)
     
  12. -tmm-

    -tmm- Senior Member

    I'm going to make a full scale B-17, then a cup of tea.
     
  13. Gerard

    Gerard Seelow/Prora

    What scale will the tea be in -tmm-??? ;)
     
  14. -tmm-

    -tmm- Senior Member

    It'll be 2:1 scale. I like a big cup of tea :)
     
  15. Owen

    Owen -- --- -.. MOD

  16. wowtank

    wowtank Very Senior Member

    If developed this has the potential to break the economy of the world!! and what about when you can print a gun!
     
  17. Deacs

    Deacs Well i am from Cumbria.

    Do you have anymore photos Owen looks good
     
  18. von Poop

    von Poop Adaministrator Admin

    If developed this has the potential to break the economy of the world!!
    Think of the (ludicrous) price of Printer ink.
    Then imagine just how ludicrous the price of 3D Printing materials will be for anything worthwhile, and the price of rights/instructions to create whatever.
    The economy of the world will remain unbroken...

    BBC News - 3D printers could create customised drugs on demand
     
  19. wowtank

    wowtank Very Senior Member

    Think of the (ludicrous) price of Printer ink.
    Then imagine just how ludicrous the price of 3D Printing materials will be for anything worthwhile, and the price of rights/instructions to create whatever.
    The economy of the world will remain unbroken...

    BBC News - 3D printers could create customised drugs on demand

    I am sure You are 99.999 recurring % right but look how the web has change the world kind of scary if we that happened to manufacturing. You used to be able to buy printers with free black toner for life they were only like £400!
     
  20. At Home Dad (Returning)

    At Home Dad (Returning) Well-Known Member

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