scad/chamfer.scad

78 lines
2.2 KiB
OpenSCAD

/// Chamfering OpenSCAD Example
/// Written by Robert Quattlebaum, 2022-12-14
///
/// This example shows a method for adding a chamfer to a certain
/// class of 3D objects where the profile in the Z dimension doesn't
/// change significantly.
///
/// You must specify the size of the chamfer, the height of the child
/// and the Z-offset for the bottom of the object. You can also specify
/// the shape of the chamfer, which can be either "cone", "curve", "curve-in",
/// or "pyramid".
///
/// This process is ultimately slow, but should be faster than using minkowski.
module chamfer(size=2, child_h=5, child_bot=0, shape="curve") {
chamfer_size=size;
module chamfer_shape() {
if (shape == "cone") {
$fn=16;
cylinder(chamfer_size/2,chamfer_size/2,0);
} else if (shape == "curve") {
$fn=4;
for( y = [0:1/$fn:1]) {
cylinder(chamfer_size/2*(1-y),chamfer_size/2/cos(180/$fn)*y,0);
}
} else if (shape == "curve-in") {
$fn=16;
intersection() {
sphere(chamfer_size/2/cos(180/$fn));
translate([0,0,chamfer_size/2])
cube(chamfer_size, center=true);
}
} else if (shape == "pyramid") {
$fn=4;
cylinder(chamfer_size/2/cos(180/$fn),chamfer_size/2,0);
}
}
module lower_chamfer() {
minkowski()
{
linear_extrude(0.0001) difference() {
square([1000,1000],center=true);
projection()children(0);
}
chamfer_shape();
}
}
module upper_chamfer() {
scale([1,1,-1])lower_chamfer()children();
}
render()difference() {
children();
translate([0,0,child_bot])lower_chamfer()children();
translate([0,0,child_bot+child_h])upper_chamfer()children();
}
}
/////////////////////////////////////////////////////////////////////////
module my_shape(h=5) {
translate([0,0,h/2]) {
difference() {
cube([50,50,h],center=true);
cube([20,20,h+1],center=true);
}
translate([20,21,0])cylinder(h=h,r=20,center=true);
}
}
h=5;
chamfer(3, child_h=h, shape="cone")
my_shape(h);