// The Estes A8-3 and C6-7 motors have diameter of 17.7 mm,
// length 69.5 mm. The Estes Alpha launch pad has rod diameter 3.4 mm.
-motor_diam = 17.7 + 0.6; // add some tolerance
+motor_diam = 17.7 + 1.2; // add some tolerance
motor_len = 69.5 + 0.5;
segment_overlap = 15;
-loose_fit_diam_diff = 0.5; // cylinder with outer diameter d1
+loose_fit_diam_diff = 1.1; // cylinder with outer diameter d1
// will fit loosely into the hole with inner diameter
// d1 + loose_fit_diam_diff
-tight_fit_diam_diff = 0.25; // cylinder with outer diameter d1
+tight_fit_diam_diff = 0.4; // cylinder with outer diameter d1
// will fit tightly into the hole with inner diameter
// d1 + tight_fit_diam_diff
-thin_wall = 0.9; // depends on the print width
+thin_wall = 1.0; // depends on the print width
thick_wall = 2*thin_wall + loose_fit_diam_diff/2;
// motor_diam + 2*thick_wall is the outer diameter of the rocket
motor_wall = thick_wall; // above the motor
clip_height = 3.5;
-clip_clearance = segment_overlap/4;
+clip_width = 1.2;
+clip_clearance = 1.0;
clip_inner_space = motor_diam/2 - 1.5;
rod_diam = 3.4 + 1;
rubber_beam_height = 3;
+rubber_beam_width = 1.5;
-fin_thickness = 1;
+fin_thickness = 1.5;
eps = 0.01;
-infty = 1000;
+infty = 250;
+
+// rod holder
+
+module rod_holder() {
+ // rod hole holder
+ hull() {
+ translate([motor_diam/2 + thick_wall + thin_wall + rod_diam/2, 0, 0])
+ cylinder(r = rod_diam/2 + thin_wall, h = thick_wall);
+ translate([motor_diam/2 + thick_wall - thin_wall - rod_diam/2, 0, 0])
+
+ cylinder(r = rod_diam/2 + thin_wall, h = 3*thick_wall);
+ }
+}
+
+module rod_hole() {
+ // rod hole
+ translate([motor_diam/2 + thick_wall + thin_wall + eps + rod_diam/2, 0, 0])
+ cylinder(r = rod_diam/2, h = infty);
+}
//----------------- MOTOR MODULE -----------------------------
fin2();
};
- // rod hole holder
- hull() {
- translate([motor_diam/2 + thick_wall - rod_diam/2 - thin_wall,
- 0, segment_overlap])
- scale([1, 1.4, 1])
- cylinder(r = rod_diam/2 + thin_wall, h = eps);
- translate([motor_diam/2 + thick_wall + thin_wall + rod_diam/2, 0, segment_overlap + rod_hole_side])
- scale([1, 1.1, 1])
- cylinder(r = rod_diam/2 + thin_wall, h = rod_hole_height);
- translate([motor_diam/2 + thick_wall - rod_diam/2 - thin_wall,
- 0, segment_overlap + 2*rod_hole_side + rod_hole_height])
- scale([1, 1.4, 1])
- cylinder(r = rod_diam/2 + thin_wall, h = eps);
- };
-
// motor clip
- rotate([0, 0, 120]) intersection() {
+ for (angle = [120, -120]) rotate([0, 0, angle]) intersection() {
translate([clip_inner_space, -infty/2,
motor_len + motor_wall + clip_clearance])
- cube([thin_wall, infty, clip_height]);
+ cube([clip_width, infty, clip_height]);
rotate([0, 0, -60])
translate([-infty/2, 0, 0]) cube(infty);
rotate([0, 0, -120])
translate([-infty/2, 0, 0]) cube(infty);
};
+
+ translate([0, 0, motor_len + motor_wall])
+ scale([1, 1, -1])
+ rod_holder();
};
module motor_module() {
cylinder(r = 3, h = infty);
};
- // rod hole
- translate([motor_diam/2 + thick_wall + thin_wall + eps + rod_diam/2, 0, 0])
- cylinder(r = rod_diam/2, h = infty);
+ rod_hole();
};
};
// -------------------- CENTRAL TUBE ---------------------
-central_tube_h = 85;
+central_tube_h = 97;
central_clip_r = 12;
central_clip_w = 4;
-central_clip_clearance = 1.5;
+central_clip_wall = 1.5;
+central_clip_clearance = 2.5;
module central_tube_solid() {
cylinder(r = motor_diam/2 + thick_wall, h = central_tube_h);
+ rod_holder();
};
module central_tube() {
translate([0, 0, -eps])
cylinder(r = motor_diam/2 + thick_wall - thin_wall,
h = infty);
- };
- // rubber band holder
- intersection() {
- cylinder(r = motor_diam/2 + thick_wall - eps, h = central_tube_h);
-/*
- translate([motor_diam/2 - thick_wall, -infty/2,
- segment_overlap + thick_wall])
- cube([thin_wall, infty, rubber_beam_height]);
-*/
- translate([-central_clip_w/2,
- central_clip_r + motor_diam/2 + thick_wall - 2*thin_wall - central_clip_clearance,
- central_tube_h/3]) rotate([0, 90, 0]) difference() {
- cylinder(r = central_clip_r, h = central_clip_w);
- translate([0, 0, -eps])
- cylinder(r = central_clip_r - thin_wall, h = central_clip_w + 2*eps);
- }
+ rod_hole();
};
};
translate([0, 0, segment_overlap])
bezier_cone([
[ 0, motor_diam/2 + thick_wall ], // start
- [ cone_h/2, motor_diam/2 + thick_wall ], // cp 1
+ [ cone_h/4, motor_diam/2 + thick_wall ], // cp 1
[ cone_h - motor_diam/2 - thick_wall, motor_diam/2 + thick_wall ], // cp 2
[ cone_h, 0 ],
], 40);
translate([0, 0, segment_overlap])
bezier_cone([
[ 0.7*thin_wall, motor_diam/2 + thick_wall - thin_wall ], // start
- [ cone_h/2-0.7*thin_wall, motor_diam/2 + thick_wall - thin_wall], // cp 1
+ [ cone_h/4-0.7*thin_wall, motor_diam/2 + thick_wall - thin_wall], // cp 1
[ cone_h - motor_diam/2 - thick_wall + thin_wall - 1.4*thin_wall, motor_diam/2 + thick_wall - thin_wall ], // cp 2
[ cone_h - 1.4*thin_wall, 0 ],
], 40);
translate([0, 0, -eps])
cylinder(r = motor_diam/2, h = segment_overlap + 2*eps);
};
- // rubber band holder
- intersection() {
- cylinder(r = motor_diam/2 + thin_wall/2, h = segment_overlap);
- translate([motor_diam/3-thin_wall/2, -infty/2,
- segment_overlap - rubber_beam_height/2 - eps])
- cube([thin_wall, infty, rubber_beam_height]);
- };
};
-module thread_holder() {
- rotate([0, 90, 0]) {
- translate([0, 0, -1.5]) difference() {
- cylinder(r = 10, h = 3);
- translate([0, 0, -eps])
- cylinder(r = 8, h = 3 + 2*eps);
- };
- };
-}
-
-// thread_holder();
+debug = 0;
-/*
+if (debug == 1) {
// debug
-difference() {
- // front_cone();
- // central_tube();
+difference($fn = 16) {
+ front_cone();
+ central_tube();
motor_module();
- translate([0, 0, -eps]) cube(infty);
+ translate([0, 0, -infty/2]) cube(infty);
};
-*/
+
+} else {
// production
$fn = 128;
rotate([0, 0, 240])
translate([motor_diam + thick_wall, 0, 0])
front_cone();
+
+}
https://www.fi.muni.cz/~kas/git / things.git / blobdiff