Welcome to Our Community

Some features disabled for guests. Register Today.

Consulting Advice Request

Discussion in 'General Talk' started by Roy Wyatt, Mar 18, 2019.

  1. Roy Wyatt

    Roy Wyatt Well-Known
    Builder

    Joined:
    Dec 15, 2014
    Messages:
    17
    Likes Received:
    1
    I'm in need of a person that could consult me on the correct CNC Equipment and Software required to assemble a complete system that would have the ability to scan an object and create a 3D exact copy of an original. I have had a problem trying to locate all of the equipment and software that works in conjunction with each other to achieve my objective. Most companies don't provide enough information on their web sites to make a determination about it's compatibility with other products. In addition, they won't reply to my enquires. Therefore, I need the advise of someone that has been there and done that and willing to pass on some of their knowledge to me. I like the concept of the OPENBUILDS concepts and would like to stare there and build off of their platform. Basically, I'm asking for someone to advise me on which components of a complete CNC Duplicator System fit together to allow new objects to be created via CNC Router. Thanks, In advance for your assistance.
     
  2. Giarc

    Giarc Master
    Moderator Builder

    Joined:
    Jan 24, 2015
    Messages:
    1,188
    Likes Received:
    637
    I do not know of any hobby grade machines that can both scan and duplicate an object with a router. You need to create the object with a CAD type software or buy the file of the object from someone who took the time to create it. I design all of my objects in Fusion 360 then cut it on my CNC machine using the Estlcam software. If I were in your position I would spend some time researching Gcode, CAD software, and CAM software. I did a lot of research into these topics prior to beginning my build.
     
  3. Giarc

    Giarc Master
    Moderator Builder

    Joined:
    Jan 24, 2015
    Messages:
    1,188
    Likes Received:
    637
    If you want to duplicate an item you need to take precise measurements of the various features of the item and then draw it in a CAD software.
     
    Peter Van Der Walt likes this.
  4. Roy Wyatt

    Roy Wyatt Well-Known
    Builder

    Joined:
    Dec 15, 2014
    Messages:
    17
    Likes Received:
    1
    I'm aware that everything I want to do cannot be accomplished by a single machine.

    1. I know that I will need a PC and CNC Software (example: SketchUp Tutorial for Beginners - Part 1 - Basic Functions - The SketchUp Essentials) to run the PC based functions.

    2. I also know that I need a CNC machine with 3 to 4 axes,(example: WorkBee Full CNC Kit),

    3. which has a motor driver controller, (example: SketchUp Tutorial for Beginners - Part 1 - Basic Functions - The SketchUp Essentials).

    4. Next, I will need a Touch Probe Duplicator (example: Digitizing Touch Probe CNC 3D digitizer 1/4" Fixed shank Router mach3 linuxcnc | eBay).

    What I don't know if these various components are compatible with one other and how they communicate with one other. I'm not sold on these partiture products and open for suggestion for a replacement. Just want to insure I have a working solution, before I start purchasing hardware/software. Thanks for your assistance! Roy

    .
     
  5. Rick 2.0

    Rick 2.0 OpenBuilds Team
    Staff Member Moderator Resident Builder Builder

    Joined:
    Dec 20, 2013
    Messages:
    2,102
    Likes Received:
    972
    It all comes down to the complexity of what you're trying to copy. Estlcam will do simple surface scanning but the metal tape approach is not appropriate for all situtions. This is something though that is easily worked around with a probe/contact switch combination. Another thread to look at would be Digitising with Blackbox

    The question is what type of objects are you wanting to copy. Are you needing continuous probing or will a simple point grid array do the job? Is it something that would be better off done optically? What is the level of complexity?
     
    GrayUK likes this.
  6. Rob Taylor

    Rob Taylor Master
    Builder

    Joined:
    Dec 15, 2013
    Messages:
    456
    Likes Received:
    181
    You're trying to build a CNC CMM, realistically. Even if you can theoretically build the thing to a sufficiently high standard, you're gonna have to look into whether software is even available that will do the appropriate scanning methods for you, because to duplicate anything just random matrices of point height measurements isn't gonna cut it.

    Then you're gonna need to fully understand tolerance stacks. You might need to measure something to two orders of magnitude higher precision than the final model comes out, so that the tolerances all the way down the line, from digitization to modelling to CAM, all the physical limitations of the production machine's force chains, it gets out the other end at least somewhat in the ballpark of what you originally measured. If you measure it to +/-0.5mm, CAD/CAM it to 0.5mm, and then your tolerance stack of your router is another 0.5mm, you might end up with two parts 1.5mm different in size and in no way compatible.

    Another issue is that metrology hates vibration. Steppers are probably out of the question- and that's aside from the fact that their positioning is +/-5%. If you're relying on the computer to actually know where the probe is, that's not realistically gonna happen. Fine for making a wooden sign, not so fine for knowing whether that pocket is 5.65 or 5.70mm across.

    Probes are a whole other can of worms. There's a reason Renishaws cost mid-four-figures. They're DIY-able, if you have the equipment and the skill, but it's not completely trivial.

    In industry, these things are built on granite slabs with linear motors and glass scales and kept in temperature- and air-movement-controlled rooms. You need to figure out how close you need to come to that to accomplish true duplication within the tolerances you require. You're probably gonna need some real metrology equipment (surface plate, squares, straightedges, various height gauges...) to be able to actually start building the thing, never mind actually calibrating and confirming its accuracy.

    I'm not trying to be discouraging, a real open hardware CMM would be awesome, but it's important to grasp the scope of what you're trying to do.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice