see bottom for more license info */
/* spin thing that erin likes */
-$fn = 500;
+$fn = 50;
+
+layer_height = 0.15;
weight = "penny";
// weight = "608zz";
bearing = "608zz";
-wall_thickness = 2;
-_608zz_radius = 22;
-penny_radius = 19.05 / 2;
+weight_lip_overhang = 0.3;
+bearing_lip_overhang = weight_lip_overhang;
+// TODO: switch wall_thickness -> wall
+wall_thickness = 3;
+wall = 3;
penny_thickness = 1.52;
+penny_radius = 19.05 / 2;
+
+_608zz_radius = 22 / 2;
+_608zz_inner_radius = 8.1 / 2;
+_608zz_cover_radius = 19.4 / 2;
+_608zz_cap_footprint_radius = 12 / 2;
+_608zz_thickness = 7;
+
weight_radius = (weight == "penny") ? penny_radius : _608zz_radius;
+weight_thickness = (weight == "penny") ?
+ penny_thickness * 5 : _608zz_thickness;
+
bearing_radius = (bearing == "608zz") ? _608zz_radius : 1/0;
+bearing_inner_radius = (bearing == "608zz") ? _608zz_inner_radius : 1/0;
+bearing_cover_radius = (bearing == "608zz")
+ ? _608zz_cover_radius + wall
+ : 1/0;
+bearing_cap_footprint_radius =
+ (bearing == "608zz") ? _608zz_cap_footprint_radius : 1/0;
+bearing_thickness = (bearing == "608zz") ? _608zz_thickness : 1/0;
+
+spinner_height = penny_thickness * 5 + 2;
arms = 3;
+module cap(bearing_inner_radius,
+ bearing_cap_footprint_radius,
+ bearing_cover_radius,
+ bearing_thickness) {
+ footprint_height = 1.6;
+ footprint_radius_safety = 0.25;
+ cap_height = 3;
+ bearing_cover_radius_safety = 0.75;
+ bearing_thickness_safety = 0.2;
+
+ difference() {
+ union() {
+ cylinder(r1 = bearing_cover_radius - tan(30) * cap_height,
+ r2 = bearing_cover_radius,
+ h = cap_height);
+ linear_extrude(height = cap_height + footprint_height) {
+ circle(bearing_cap_footprint_radius - footprint_radius_safety); }
+ linear_extrude(height = cap_height
+ + footprint_height
+ + bearing_thickness / 2
+ - bearing_thickness_safety) {
+ circle(bearing_inner_radius); } }
+ translate([0, 0, -0.01]) {
+ cylinder(r1 = bearing_inner_radius + tan(30) * (cap_height - 1),
+ r2 = bearing_inner_radius,
+ h = cap_height - 1); } } }
+
+module fillet(r) {
+ offset(r = -r) { offset(delta = r) { children(); } } }
+
+module spin_footprint(weight_radius,
+ bearing_radius,
+ round_extra,
+ wall,
+ arms) {
+ thinner_radius = (bearing_radius < weight_radius)?
+ bearing_radius : weight_radius;
+ fillet(thinner_radius / 2) {
+ for(arm = [0 : arms - 1]) {
+ hull() {
+ circle(bearing_radius + round_extra);
+ rotate( (arm / arms) * 360 ) {
+ translate([bearing_radius + wall + weight_radius, 0]) {
+ circle(weight_radius + round_extra); } } } } } }
+
+module mirrored(axis) {
+ children();
+ mirror(axis) children(); }
+
module spin(weight_radius,
- arms,
- wall_thickness,
- bearing_radius) {
- bearing_holder_radius = bearing_radius + wall_thickness;
- weight_holder_radius = weight_radius + wall_thickness;
-
- circle(bearing_holder_radius);
-
- /*
- * imagine a right triangle with one point at the origin, at the
- * center of the spinning bearing holder, one point in the middle of
- * the weight holder, and one point at the center of a circle tangent
- * to the first two, called the joiner circle.
- * the radius of the joiner circle is the arithmetic average of the
- * weight holder and bearing holder.
- */
- joiner_radius = (bearing_holder_radius + weight_holder_radius) / 2;
- /* a: goes between the center of the weight holder and the center of
- the joiner circle. */
- a = joiner_radius + weight_holder_radius;
- /* b: length of the base, which goes along the x-axis between
- the origin and the center of the weight holder. */
- b = weight_holder_radius + bearing_holder_radius;
- /* c: goes between origin and joiner circle. */
- c = bearing_holder_radius + joiner_radius;
-
- /* A: angle at the origin, between the base and hypotenuse.
- it is calculated using law of cosines, given the lengths of
- all 3 sides of the triangle. */
- A = acos((pow(b, 2) + pow(c, 2) - pow(a, 2)) / (2 * b * c));
- /* find the center of the joiner circle */
- joiner_x = cos(A) * c;
- joiner_y = sin(A) * c;
-
- /* find the points where the circles meet */
- bearing_joiner_point = [cos(A) * bearing_holder_radius,
- sin(A) * bearing_holder_radius];
- bearing_weight_point = [bearing_holder_radius, 0];
- /* C: angle between x-axis and line-segment between center of weight
- holder and center of joiner.
- it is calculated using law of cosines, given the lengths of
- all 3 sides of the triangle. */
- C = acos((pow(a, 2) + pow(b, 2) - pow(c, 2)) / (2 * a * b));
- weight_joiner_point = [b - cos(C) * weight_holder_radius,
- sin(C) * weight_holder_radius];
- for(arm = [0 : arms - 1]) {
- rotate(arm * 360.0 / arms) {
- difference() {
- polygon([bearing_weight_point,
- bearing_joiner_point,
- weight_joiner_point]);
- translate([joiner_x, joiner_y]) {
- circle(joiner_radius); } }
- mirror(v = [0, 1, 0]) {
- difference() {
- polygon([bearing_weight_point,
- bearing_joiner_point,
- weight_joiner_point]);
- translate([joiner_x, joiner_y]) {
- circle(joiner_radius); } } }
- translate([weight_holder_radius + bearing_holder_radius, 0]) {
- circle(weight_holder_radius); } } } }
+ weight_thickness,
+ bearing_radius,
+ bearing_thickness,
+ weight_lip_overhang = 0.3,
+ bearing_lip_overhang = 0.3,
+ wall = 3,
+ arms = 3,
+ layer_height = 0.15) {
+ layer_height = 0.15;
+ thicker_thickness = (bearing_thickness > weight_thickness) ?
+ bearing_thickness : weight_thickness;
+ calculated_height = thicker_thickness + 2 * wall;
+ layers = 2 * ceil(ceil(calculated_height / layer_height) / 2);
+ actual_height = layers * layer_height;
+ round_radius = actual_height / 2;
+
+ old_start = 0;
+ old_end = (layers / 2) - 1;
+
+ new_start = old_end / 16;
+ new_end = old_end;
+
+ old_range = old_end - old_start;
+ new_range = new_end - new_start;
+
+ factor = new_range / old_range;
+
+ initial_adjacent = round_radius - (new_start * layer_height);
+ initial_angle = acos(initial_adjacent / round_radius);
+ initial_round_extra = initial_adjacent * tan(initial_angle);
+
+ mirrored([0, 0, 1]) {
+ for(layer = [0 : (layers / 2) - 1]) {
+ translate([0, 0, layer * layer_height - actual_height / 2]) {
+ linear_extrude(height = layer_height) {
+ new_layer = (layer - old_start) * factor + new_start;
+ adjacent = round_radius - (new_layer * layer_height);
+ angle = acos(adjacent / round_radius);
+ round_extra = adjacent * tan(angle) - initial_round_extra;
+ echo(round_extra);
+ spin_footprint(weight_radius,
+ bearing_radius,
+ round_extra,
+ wall,
+ arms); } } } } }
/*
This file is part of 3d-printables.
projects / ozzloy@gmail.com / 3d-printables / blobdiff