Here's the hollowed out version
module tyre() {
$fn=100;
difference () {
union () {
translate ([0,0,-1.5])cylinder(15,34,34);
rotate_extrude (angle=45, convexity = 9) translate ([32,-0.5,-2.75]) circle (r=2);
rotate_extrude (angle=45, convexity = 9) translate ([32,12.5,-2.75]) circle (r=2);
difference () {
union () {
translate ([0,0,-2.5])cylinder(17,32,32);
translate ([0,0,-3])cylinder(18,27,27);
}
translate ([0,0,13.6])cylinder(1.5,20,25);
translate ([0,0,-3.1])cylinder(1.5,25,20);
}
}
translate ([0,0,-3])cylinder(18,17,17);
translate ([0,0,0.5])cylinder(11,26,26); // hollow out tyre
for (z = [0:12:360])rotate(a=(0)+z,v=[0,0,1])translate([28.8,0,-3]) cube ([6,3.5,8]);
for (z = [0:12:360])rotate(a=(30)+z,v=[0,0,1])translate([28.8,0,7]) cube ([6,3.5,8]);
}
difference () {
union () {
translate ([0,0,-0.5])cylinder(13,32,32);
rotate_extrude (angle=45, convexity = 9) translate ([30,0.5,-2.75]) circle (r=2);
rotate_extrude (angle=45, convexity = 9) translate ([30,11.5,-2.75]) circle (r=2);
}
translate ([0,0,-3])cylinder(18,17,17);
translate ([0,0,0.5])cylinder(14,20,20);
}
}
tyre ();
I think this version may go over the rim of the hub so long as you print using TPU
Alwyn
