Close



Results 1 to 4 of 4
  1. #1

    How Create a Pattern into a Solid

    I have been using tinkercad and it might be time to step up to new software to create more complex things. What would be the easiest way to create something like this, having a pattern throughout a basic cylinder? and also the simplest software to use to do so? Thanks!
    Attached Images Attached Images

  2. #2
    Staff Engineer
    Join Date
    Jun 2014
    Posts
    878
    This is again one of those quandry projects. You're asking for a simple answer to a complex problem and yet want an easy, simple way to accomplish it.

    It really boils down to "how much learning are you willing to undertake?"

    I'm confident that Fusion 360 would accomplish your objective. It's free to hobbyists and is insanely powerful. Along with that power comes a bit of complexity. For simple shapes, it's simple enough to use. I'm familiar with Tinkercad, which uses geometric primitives to construct models. Fusion 360 uses sketch based modeling. You create an outline of a shape and extrude, subtract, add, rotate, translate, etc that shape and others to build your model. I'm not well-versed enough in F360 to suggest how one would make this array.

    On another approach, OpenSCAD would also be a suitable, free, multi-platform program to create this model. It uses primitives just as Tinkercad, but the creation is done via text and script. I have had a bit more experience with OpenSCAD and could possibly create this model, hence my recommendation/suggestion. As an example, one might create a cylinder with the base diameter smaller than the top diameter, then create an internal cylinder of the same ratio, subtracting the inner from the outer.

    The fun comes in when you use for-loops to generate the cut-outs necessary to create the mesh. It's difficult for me to discern the mesh design, but you may have to create two of the above, each with its own array of cut-outs, then nest them.

    If you are comfortable with simple programming and managing syntax (and can type comfortably), OpenSCAD may be the answer. I believe that it has a less-steep learning curve than F360, but I suppose it's because my limited grey matter is better able to remember (or find) the stuff that makes it work for me.

  3. #3
    Super Moderator curious aardvark's Avatar
    Join Date
    Jul 2014
    Posts
    8,818
    Im with fred. Any decent cad package that you learn to use will do that.

    Openscad will do it in about 6 lines of script.

    For the tringulat cuttouts you simply have two 'loops' that create offset circular cutouts and move up the cylinder at different heights.
    Actually you could most likely do it with a single line if your maths is good enough.
    I'm the first to admit my maths is lousy - but fortunately openscad does allow for the trial and error/rinse and repeat methodology of algebra :-)

    Go on then a test for a wet wednesday afternoon -
    I will be back !

  4. #4
    Super Moderator curious aardvark's Avatar
    Join Date
    Jul 2014
    Posts
    8,818
    well, it needs some refining. Or maybe it doesn't - depends how you look at it lol
    This script will do some odd things that may produce a more interesting design.
    Dodgy, it most definitely is.

    But it - for a given definition of the word 'works' - works :-)



    so just copy and paste everything in the quotes box below into openscad and press f5 to generate a quick render and f6 to generate something that can be exported as a printable stl file.
    There are various tweaks that can be added - and if I can ever be arsed I might (dont'hold your breath) dive back in and sort the maths out.

    It's weird, that for the first 45 years of my life I had absolutely no use for algebra.
    But since finding openscad, I'm bloody glad that even the minimal amount that sunk in at school - did actually sink in !

    It - probably - won't generate the exact same mesh as above - but it will certainly make enough interesting shapes to keep a lot of printers busy for an awful long time :-)

    // Curious Aardvark Designs: 'Really Dodgy Bin/Vase generator'

    // variables - change to change the shape/bin/vase generated


    br=3; // 'roundness' of bin. from 3 for triangular to 100 for reallly round. Drastically effects rendering time :-)
    bb=30; // bin bottom diameter
    bt=50; // bin top diameter
    bh=70; // height of bin
    bs=2; // how thick the bin sides are.
    bbt=2; // thickness of bin base and top rim
    cd=4; // cutout diameter
    cs=4; // cutout shape - 3=triangle, 4=square, 5=hexagon etc
    nc=20; // number of cutouts per layer - needs to be an even number
    sl=1; // space between layers
    lro=7; // layer rotation offset

    nl1=(bh-2*bbt)/(cd+sl*2); // number of layers
    nl2=(bh-2*bbt)-(nl1*sl);
    $fn=br;

    module bin(){
    difference(){
    cylinder(d1=bb, d2=bt, h=bh,$fn=br);
    translate([0,0,bbt]) cylinder(d1=bb-2*bs,d2=bt-2*bs,h=bh-(bbt)+1,$fn=br);

    // Generating the pattern of piercings

    for (z = [1:nl1]) {
    for (i = [1:nc]) rotate([0,0,(360/(nc)*i)+lro*z])translate([-(bt+4)/2,0,((bbt)+(cd)*sl)*z]) rotate([0,90,0]) cylinder(d=cd,h=3*bt+4,$fn=cs);
    } // end second loop

    } // end diff
    } // end mod
    bin();
    The actual script is just 4 lines. Everything else is either comments or a list of variables.
    2 lines define the actual bin size and shape.
    2 lines define the number, shape and positioning of the cutouts.

    It's rough and will no doubt cause any actual 'programmer' to have a heart attack.
    But like most of my openscad scripts - it works, and - mostly - does what I want it to. :-)
    Last edited by curious aardvark; 09-02-2020 at 11:29 AM.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •