$fn = 300;

// * c w
part = "c";

slot_center_spacing = 25.4;

ramp_height = 5;
ramp_slot_mid = 4.25;
ramp_depth = 2.5;

deramp_height = 1;
deramp_depth = (ramp_depth / ramp_height) * (ramp_height - deramp_height);

bulk_radius = 2;

rod_radius = 4.2;
bearing_radius = 4;
bearing_cut_depth = 2;

core_bump_radius = 1;
core_bump_height = 2;

e = 0.02;

outer_radius = rod_radius + bearing_radius + bulk_radius;
echo("outer_radius=", outer_radius);

echo("max_radius=", outer_radius + ramp_depth);

mid = slot_center_spacing - ramp_slot_mid - ramp_slot_mid;

total_height = deramp_height + ramp_height + mid + ramp_height + deramp_height;
echo("total_height=", total_height);

if (part == "*" || part == "c") {
    color("grey", 0.6)
    intersection() {
        wheel();
        core_mask();
    }
}

if (part == "*" || part == "w") {
    color("red", 0.6)
    difference() {
        wheel();
        core_mask();
    }
}

module core_mask() {
    rotate_extrude()
    polygon([
        [0, total_height + e],
        [0, 0 - e],
        
        [rod_radius + bearing_radius + core_bump_radius, 0 - e],
        [rod_radius + bearing_radius + core_bump_radius, 0],
        [rod_radius + bearing_radius, core_bump_height],
        [rod_radius + bearing_radius + core_bump_radius, total_height + e],
    ]);
}

module wheel() {
    // deramp
    // ramp
    //   [tip]
    // ramp
    // mid
    // ramp
    //   [tip]
    // ramp
    // deramp

    difference() {
        rotate_extrude()
        polygon([
            [rod_radius, total_height],
            [rod_radius, 0],
            
            [outer_radius + deramp_depth, 0],
            [outer_radius + ramp_depth, deramp_height],
            [outer_radius, deramp_height + ramp_height],
            [outer_radius, deramp_height + ramp_height + mid],
            [outer_radius + ramp_depth, deramp_height + ramp_height + mid + ramp_height],
            [outer_radius + deramp_depth, total_height],
        ]);
        
        for (a=[0:45:360]) {
            translate([0, 0, -e])
            rotate([0, 0, a])
            cube([rod_radius + bearing_cut_depth, 1, e + total_height + e]);
        }
    }
}