how to model this "spliny" shape

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how to model this "spliny" shape

 Any suggestions for how to model this shape:https://drive.google.com/file/d/1dLyvvEzK3i3CQwC223ZVIVi2aXJT2E3K/view?usp=sharing It’s purpose is to fit over the fingers of an individual and onto their palm (before their thumb).  A stylus is attached via the dove-tail cuts in the top.  This is for individuals with motor disabilities.  The goal would be to make the palm outline scalable without affecting the mounting points on top which have to be a standard size.  Also the thickness of the ring would need to stay constant (or better yet be defined by a parameter).  Finally, it should be possible to round or chamfer at least the inside edges of the ring so as not to irritate the skin of the person wearing it unnecessarily. Thoughts? Thanks,Ken_______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
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Re: how to model this "spliny" shape

 - design it in 2D (e.g. with inkscape and import it as SVG or DXF), - linear extrude it - round it with minkowski() adding a sphere - to customize the size use scale factors -- Sent from: http://forum.openscad.org/_______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
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Re: how to model this "spliny" shape

 If you can handle it being a bit more regular you could model the inside with four circle meeting tangentially. It is a bit of maths but I did it for three to make a replacement glass for an Avo multimeter.function sqr(x) = x * x;\$fs = 0.25;\$fa = 1;width = 148;h1 = 25.4;h2 = 65;r1 = 25.4;h = h2 - h1;l = width / 2 - r1;r2 = 0.5 * (sqr(h) - sqr(r1) + sqr(width / 2 - r1)) / (h - r1);w = l * r2 / (r2 - r1);echo(r2);offset = 0 *5.3 / 2;linear_extrude(height = 3)offset(-offset)hull() {    translate([-width / 2, -offset])        square([width, 1]);        for(side = [-1, 1])        translate([side * l, h1])            #circle(r1);        intersection() {        translate([0, h2 - r2, 1])            #circle(r2);                translate([-w, 0])            square([2 * w, h2]);    }}    Then you would use offset to make the outside edge and take the difference. Then linear extrude it and round with minkowski.You could also model it with Bezier splines for a more organic shape.On Sun, 27 Jan 2019 at 02:26, Parkinbot <[hidden email]> wrote:- design it in 2D (e.g. with inkscape and import it as SVG or DXF), - linear extrude it - round it with minkowski() adding a sphere - to customize the size use scale factors -- Sent from: http://forum.openscad.org/ _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org