complete hull of shoulder, upper and forearm for 3030 spool holder

[ozzloy@gmail.com/3d-printables] / mk2-haribo-spool-holder.scad

/* GNU AGPLv3 (or later at your option)
   see bottom for more license info */

/* measurements from misumi's 3030 aluminum extrusion data sheet
   https://us.misumi-ec.com/pdf/fa/2012/p2_0545.pdf
*/

x = 30;
y = 30;
diagonal = sqrt(pow(30/2, 2) + pow(30/2, 2));
opening_width = 8;
inner_block = 12;

outer_block = (30 - 16.5) / 2;
wall = 2;

$fn = 100;

module 3030_arm_half(){
  // inner block
  square(inner_block / 2);

  // diagonal arms connecting inner block to outer blocks
  rotate(45) {
    square([diagonal - wall, wall / 2]); }

  // outer block, without the wall part since wall has rounded corner
  translate([x / 2 - outer_block, y / 2 - outer_block]) {
    square(outer_block - wall); }

  // outer arms covering the opening
  translate([(opening_width + wall) / 2, y / 2 - wall]) {
    square([(x - opening_width - wall) / 2 - wall, wall]); }
  // rounded part at entrace to inside
  translate([(opening_width + wall) / 2, (y - wall) / 2]){
    circle(d = wall); }
  // rounded part around outside of extrusion
  corner_squish = 0.1;
  translate([x / 2 - wall + corner_squish, y / 2 - wall + corner_squish]) {
    circle(wall - corner_squish); } }

module 3030_profile(){
  arms = 4;
  for(arm = [0:arms - 1]) {
    rotate(arm * 360 / arms) {
      3030_arm_half();
      mirror(){ 3030_arm_half(); } } } }

module 3030_sleeve_profile(){
  difference() {
    square(40, true);
    minkowski() {
      3030_profile();
      circle(0.2);} } }

module fillet(r) {
   offset(-r) {
     offset(r) {
       children(); } } }

module upper_arm_profile(){
  square(40, true);

  a = [20, -20];
  b = [34.1, 0];
  c = [6.25, 20];
  points = [a, b, c];

  arm_radius = 11.35;
  arm_center = [61.8, 140.4];
  hull() {
    polygon(points);
    translate(arm_center) {
      circle(arm_radius); } } }

module forearm_profile() {
  fillet(-5) {
    difference() {
      upper_arm_profile();
      translate([-20, -20]) {
        square(151); } } } }

module upper_arm_hull() {
  linear_extrude(height = 15) {
    upper_arm_profile(); } }

module forearm_hull() {
  linear_extrude(height = 120.5) {
    forearm_profile(); } }

module shoulder_hull() {
  translate([-20, -20, 0]) {
    cube([40, 40, 35]); } }

shoulder_hull();
upper_arm_hull();
forearm_hull();

original_spool_holder();

module original_forearm_profile() {
  %projection(true) {
    translate([-315, 0, -80]) {
      import("Spool-holder.stl"); } } }

module original_upper_arm_profile() {
  %projection(true) {
    translate([-315, 0, -2]) {
      import("Spool-holder.stl"); } } }

module original_spool_holder() {
  %translate([-315, 0, 0]) {
    import("Spool-holder.stl"); } }

/*
  This file is part of 3d-printables.

  3d-printables is free software: you can redistribute it and/or modify
  it under the terms of the GNU Affero General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  (at your option) any later version.

  3d-printables is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU Affero General Public License for more details.

  You should have received a copy of the GNU Affero General Public License
  along with challenge-bot.  If not, see <http://www.gnu.org/licenses/>.
*/