chiark / gitweb /
pull-cord-keeper: backxgap
[reprap-play.git] / pull-cord-keeper.scad
1 // -*- C -*-
2
3 hoopthick = 3;
4
5 hinnerrad = 15;
6 houterrad = hinnerrad + hoopthick;
7 hcentredist = 10;
8
9 blockdepth = 5;
10 blockwidth = hcentredist*2 + 6;
11
12 height = 20;
13
14 ziglen = hcentredist/2;
15
16 feedxgap = 5;
17 feedzgap = 5;
18 ribsgap = 1;
19
20 ribdepth = 3;
21 ribheight = 4;
22
23 backxgap = 1;
24
25 blockoverlapcnr = 5;
26
27 module Oval(centredist, rad) {
28   hull() {
29     translate([-centredist/2,0,0]) circle(r=rad);
30     translate([+centredist/2,0,0]) circle(r=rad);
31   }
32 }  
33
34 module Hoop(){
35   difference(){
36     hull(){
37       Oval(hcentredist, houterrad);
38       translate([0, (blockdepth + hoopthick)/2 + hinnerrad])
39         square([blockwidth,
40                 blockdepth + hoopthick],
41                center=true);
42     }
43     Oval(hcentredist, hinnerrad);
44   }
45 }
46
47 module Positive(){
48   translate([0,0, -height/2])
49     linear_extrude(height=20)
50     Hoop();
51 }
52
53 module Ribs(){
54   imax = ceil(height*2 / ribheight);
55   for (i=[-imax:imax]) {
56     hull(){
57       translate([-ribdepth/2,
58                  ribheight*i,
59                  0])
60         polygon([[0,          0],
61                  [ribdepth, -ribheight],
62                  [ribdepth, +ribheight]]);
63       translate([50, 0])
64         square([1, height*2], center=true);
65     }
66   }
67 }           
68
69 module Division(cutmore) {
70   mirror([0,0,1]) {
71     translate([0, 0, -cutmore*feedzgap/2]) {
72       translate([-ziglen + -cutmore*feedxgap/2, -100, 0])
73         cube([100, 100, 50]);
74     }
75   }
76   translate([blockwidth/2 - blockoverlapcnr + -cutmore*backxgap,
77              -50,
78              -50])
79     cube([100, 100, 100]);
80
81   translate([50,
82              hinnerrad/2 + houterrad/2 + blockdepth/2 + -cutmore*ribsgap,
83              0])
84     rotate([-90,0,90])
85     linear_extrude(height=100)
86     Ribs();
87 }
88
89 module SDemo(){
90   //difference(){
91   %  Positive();
92   //  Division(0);
93   //}
94   Division(-1);
95 }
96
97 module A(){
98   difference(){
99     Positive();
100     Division(+1);
101   }
102 }
103
104 module B(){
105   intersection(){
106     Positive();
107     Division(-1);
108   }
109 }
110
111 module Demo(){
112   color("red") A();
113   color("blue") B();
114 }
115
116 //Ribs();
117 //Demo();
118
119 //A();
120 //B();
121 //%Division(+1);
122
123 //Hoop();
124
125 Demo();