3 // brk_*: "bracket", the Topeak MTX bracket
4 // rack_*: the Tortec rack
5 // adapt_*: the adapter, ie this file
9 brk_recess_actual = 5.20;
11 rack_rail_dia = 10.40 + 0.50;
12 rack_width_inner = 115.86 + 1.0; // between insides of rails
14 rear_elevation_nominal = 10.04; // top of rack to bottom of bracket
15 rear_to_front_distance = 230;
21 strap_barrel_dia = 12;
30 main_sz_z = beside_strap_sz*2 + strap_w;
32 brk_bottom_y = -brk_recess_actual;
33 adapt_main_top_y = brk_bottom_y + general_gap_y;
36 rack_rail_x = -(rack_width_inner/2 + rack_rail_dia/2);
37 rack_rail_outer_x = -(rack_width_inner/2 + rack_rail_dia);
39 grasp_large_r = (rack_rail_dia + grasp_sz)/2;
40 grasp_large_x = rack_rail_outer_x + grasp_large_r;
42 block_x = grasp_large_x + grasp_large_r/2;
43 block_y_min = adapt_main_top_y - main_sz_y;
45 strap_barrel_x = rack_width_inner/2 + strap_barrel_dia/2;
47 rack_shear_ratio = rear_elevation_nominal / rear_to_front_distance;
49 module GraspElevation(){
51 translate([ grasp_large_x, adapt_main_top_y - grasp_large_r ])
52 circle(grasp_large_r);
54 translate([ grasp_large_x, $rack_rail_y - rack_rail_dia/2 ])
55 circle(grasp_large_r);
57 translate([ grasp_large_x, $rack_rail_y + rack_rail_dia/2 ])
58 circle(grasp_large_r);
62 module BlockElevation(){
63 rectfromto([ +block_x, adapt_main_top_y ],
64 [ -block_x, block_y_min ]);
73 multmatrix([ [ 1, 0, 0, 0 ],
80 module GraspFixingElevation(){
83 mirror([1,0]) GraspElevation();
84 translate([ strap_barrel_x, $strap_barrel_y ])
85 circle(strap_barrel_dia/2 + strap_guide_sz);
88 rectfromto([0, $rack_rail_y],
89 [rack_width_inner, 50]);
91 translate([ rack_rail_x, $rack_rail_y ])
92 circle(r = rack_width_inner/2 - rack_rail_x, $fa=1);
94 [ rack_width_inner/2, 0 ],
95 [ rack_width_inner/2, $rack_rail_y - rack_rail_dia/2 ],
96 [ -block_x, block_y_min ],
103 module StrapBarrelElevation(){
104 translate([ strap_barrel_x, $strap_barrel_y ])
105 circle(strap_barrel_dia/2);
110 $rack_rail_y = brk_bottom_y - $elevation_nominal
111 - general_gap_y - rack_rail_dia/2;
113 $strap_barrel_y = $rack_rail_y + rack_rail_dia/2 + strap_barrel_dia/2;
121 RackShear() MainExtrude(){
122 StrapBarrelElevation();
126 RackShear() MainExtrude(){
127 GraspFixingElevation();
130 translate([0,0, main_sz_z/2]) linextr(-strap_w/2, +strap_w/2) {
131 translate([ rack_width_inner/2 - strap_th, 0 ])
132 rectfromto([ 0, -50 ], [ 50, 50 ]);
137 RackShear() linextr(-10, main_sz_z+10) {
140 translate([ rack_rail_x, $rack_rail_y ]){
142 for (dx = [-rack_rail_dia, 0])
144 circle(r= rack_rail_dia/2);
153 Principal($elevation_nominal=0);