3 // use shell thickness 1.50
4 // use fill density 40%
8 tube_dia = 27.5 + 1.625;
13 backflange_hole_dy = -1;
14 lockshaft_dia = 14.35;
28 mountscrew_dia = 4 + 0.5;
29 clipbolt_dia = 5 + 0.6;
31 mountscrew_washer = 10;
39 tube_rear_extra_th = 1;
41 divide_shaft_w = 1.75;
43 divide_head_dx = 1.75;
49 divide_fudge_r = 4.75;
52 backflange_angle = 20;
56 lockshaft_r = [1, 1] * lockshaft_dia / 2;
59 tube_or = tube_dia/2 + tube_th;
60 back_ohw = back_gap/2 + backflange_th;
61 backflange_ymin = tube_dia/2 + backflange_d;
63 lock_0y = tube_dia/2 + lock_d/2 + midweb_d;
64 lock_0x = lock_w/2 - lock_d/2;
65 lock_0 = [lock_0x,lock_0y];
67 lock_or = [lock_w, lock_d]/2 + [front_th,front_th];
69 module oval(sz){ // sz[0] > sz[1]
74 translate([sx * (xr-yr), 0])
81 // http://mathworld.wolfram.com/Circle-CircleIntersection.html
82 R = tube_or + join_cr;
83 r = lock_or[1] + join_cr;
84 d = dist2d( [0,0], lock_0 );
85 x = (d*d - r*r + R*R) / (2*d);
86 y = sqrt( R*R - x*x );
88 echo(lock_0x, lock_0y, R,r, d, x,y);
92 rotate(atan2(lock_0y, lock_0x)) {
100 module DivideHook(){ ////toplevel
104 translate([-1,0] * (w + d + w)){
106 translate([-(w + w+d) * sx, 0]) circle(r= w);
110 translate([-10*w, -10*w]) square([20*w, 10*w]);
118 br = tube_dia/2 + tube_th;
121 offset(r=divide_gap) DivideHook();
123 translate([-2*w,0]) mirror([0,1]) square([4*w, 4*w]);
130 br = tube_dia/2 + tube_th;
133 translate([br - tube_th/2,0]) {
139 translate([-2*w, 0]) mirror([0,1]) square(4*w);
143 module DivideSurround(){
150 translate([-(4*w + 2*d), 8*w]) circle(r=w);
155 module DivideInPlace(){
156 rotate([0,0, -divide_angle])
157 translate([ -tube_dia/2 -tube_th/2, 0])
161 module MainPlan(){ ////toplevel
167 for (t=[0, tube_rear_extra_th])
171 rotate([0,0, backflange_angle])
172 translate([-back_ohw,0]) mirror([0,1])
173 square([back_ohw*2, backflange_ymin]);
175 translate([0, lock_0y]){
181 polygon([[0,0], lock_0, [-lock_0[0], lock_0[1]]]);
185 rotate([0,0, backflange_angle])
186 translate([-back_gap/2,1]) mirror([0,1])
187 square([back_gap, backflange_ymin+2]);
192 DivideInPlace() DivideSurround();
194 translate([0, lock_0y]){
195 oval([lock_w/2, lock_d/2]);
198 circle(r = tube_dia/2);
200 DivideInPlace() DivideCut();
201 DivideInPlace() DivideCutB();
205 lockshaft_or = lockshaft_r + [clip_th,clip_th];
206 cliprecess_ymax = cliprecess_h - lockshaft_r[1];
207 clip_ymin = cliprecess_ymax - total_h;
208 clip_ogap = clip_gap + clip_th*2;
210 module ClipElevationPositive(){
213 translate([0, -lockshaft_or[1] * sqrt(2)])
214 square(center=true, 0.5);
216 translate([-lockshaft_or[0], 0])
217 square([lockshaft_or[0]*2, cliprecess_ymax]);
218 translate([-clip_ogap/2, 0]) mirror([0,1]) square([clip_ogap, -clip_ymin]);
221 module ClipElevationNegative(){
223 for (y=[0, cliprecess_ymax+1])
227 translate([-clip_gap/2, 1]) mirror([0,1]) square([clip_gap, 2-clip_ymin]);
230 module ClipElevation(){
232 ClipElevationPositive(1);
233 ClipElevationNegative(0);
237 module ExtrudeClipElevation(extra=0){
239 lock_0y + lock_d/2 + clip_d + extra,
242 linear_extrude(height= clip_d + extra*2, convexity=100)
246 module ThroughHole(r, y, z, x=-50) {
249 cylinder(r=r, h=100, $fn=20);
252 module MountingHoleCylinders(r, x=-50){
253 for (z=[ 1/4, 3/4 ]) {
254 rotate([0,0, backflange_angle])
256 -tube_dia/2 -0.5*backflange_d + backflange_hole_dy,
262 module ThroughHoles(){
263 MountingHoleCylinders(mountscrew_dia/2);
265 ThroughHole( clipbolt_dia/2,
266 lock_0y + lock_d/2 + clip_d/2 + front_th/2,
267 total_h - cliprecess_h - clip_th - clip_d/2 );
270 module MainPositive(){
273 linear_extrude(height=total_h, convexity=100) MainPlan();
274 ExtrudeClipElevation() ClipElevationPositive();
276 ExtrudeClipElevation(1) ClipElevationNegative();
280 module Bracket(){ ////toplevel
287 module TestTopEdge(){ ////toplevel
289 translate([0,0, -total_h])
292 translate([-200,-200,0])
297 module TestClipBoltHole(){ ////toplevel
300 translate([0, 0, -5])
302 translate([-4, lock_0y + lock_d/2 + 1, 0])
305 translate([-200, lock_0y + lock_d/2 + 0.1])
306 cube([400, 400, total_h-20]);
310 module Demo(){ ////toplevel
312 color("blue") MountingHoleCylinders(mountscrew_dia/2 - 0.1);
313 color("black") MountingHoleCylinders(mountscrew_washer/2,
317 module DivideDemo(){ ////toplevel
318 color("black") translate([0,0,-2]) MainPlan();
319 color("grey") DivideInPlace() DivideHook();
320 color("blue") translate([0,0,-4]) DivideInPlace() DivideCut();
324 //ClipElevationPositive();
329 //TestClipBoltHole();