| 1 | // Threads for acorn model |
| 2 | // Copyright (c) 2017 Clinton Ebadi <clinton@unknownlamer.org> |
| 3 | |
| 4 | use <screw_threads.scad> // http://www.thingiverse.com/thing:1686322 |
| 5 | |
| 6 | AUTO_CALCULATE = -1; |
| 7 | |
| 8 | internal_thread_tolerance = 0.3; |
| 9 | external_thread_tolerance = 0.2; |
| 10 | thread_angle = 50; |
| 11 | |
| 12 | module acorn (thread_pitch = 3.0, |
| 13 | thread_size = 2.5, |
| 14 | thread_height = 3.5, |
| 15 | thread_tooth_height = AUTO_CALCULATE, |
| 16 | |
| 17 | inner_d = 24.5, |
| 18 | base_height = AUTO_CALCULATE, |
| 19 | wall_thickness = AUTO_CALCULATE, |
| 20 | outer_d = AUTO_CALCULATE, |
| 21 | |
| 22 | keychain = true) { |
| 23 | |
| 24 | // derived settings |
| 25 | wall_thickness = (wall_thickness == AUTO_CALCULATE) ? thread_size : wall_thickness; |
| 26 | outer_d = (outer_d == AUTO_CALCULATE) ? inner_d + wall_thickness*2 : outer_d; |
| 27 | thread_tooth_height = (thread_tooth_height == AUTO_CALCULATE) ? ((thread_pitch - 0.4 > 0) ? thread_pitch - 0.4 : thread_pitch) : thread_tooth_height; |
| 28 | base_height = (base_height == AUTO_CALCULATE) ? inner_d : base_height; |
| 29 | |
| 30 | |
| 31 | module acorn_thread (outer_d = outer_d, internal = false, ring = true) { |
| 32 | if (internal) { |
| 33 | outer_ring_d = outer_d+max(thread_size, wall_thickness)+1; |
| 34 | echo ("outer ring = ", outer_ring_d); |
| 35 | ScrewHole (outer_diam=outer_d, height = thread_height, pitch = thread_pitch, tooth_height = thread_tooth_height, tooth_angle = thread_angle, tolerance=internal_thread_tolerance) { |
| 36 | if (ring) cylinder (d = outer_ring_d, h = thread_height); |
| 37 | } |
| 38 | } |
| 39 | |
| 40 | if (!internal) { |
| 41 | difference () { |
| 42 | ScrewThread (outer_diam=outer_d, height = thread_height, pitch = thread_pitch, tooth_height = thread_tooth_height, tooth_angle = thread_angle, tolerance=external_thread_tolerance); |
| 43 | cylinder (d = outer_d-wall_thickness-thread_size-0.01, h = thread_height * 4, center=true); |
| 44 | } |
| 45 | } |
| 46 | } |
| 47 | |
| 48 | module nut_body (h = base_height, d = outer_d, nub = false) { |
| 49 | translate ([0 ,0, h]) { |
| 50 | intersection () { |
| 51 | union () { |
| 52 | resize ([d, d, h*2]) sphere (d=h*2); |
| 53 | if (nub) { |
| 54 | translate ([0, d/2-wall_thickness/2, -thread_height]) sphere (d=wall_thickness*2, $fs = 0.1); |
| 55 | } |
| 56 | } |
| 57 | translate ([0 ,0, -h/2]) cube ([d*2, d*2, h], center=true); |
| 58 | } |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | module nut () { |
| 63 | difference () { |
| 64 | nut_body (); |
| 65 | translate ([0, 0, wall_thickness + 0.01]) nut_body (d=outer_d-wall_thickness*2, nub=false); |
| 66 | } |
| 67 | |
| 68 | translate ([0, 0, base_height-0.1]) acorn_thread (outer_d = outer_d); |
| 69 | } |
| 70 | |
| 71 | |
| 72 | module cap_keychain_holes (hole_d=3, spacing=15 /*12*/) { |
| 73 | h=100; |
| 74 | translate ([-spacing/2, 0, 0]) cylinder (d=hole_d, h=h, $fs=0.1); |
| 75 | translate ([spacing/2, 0, 0]) cylinder (d=hole_d, h=h, $fs=0.1); |
| 76 | } |
| 77 | |
| 78 | module cap () { |
| 79 | scale_f = outer_d / 171; |
| 80 | difference () { |
| 81 | scale ([scale_f, scale_f, scale_f]) { |
| 82 | difference () { |
| 83 | union () { |
| 84 | translate ([0, 0, -1]) import ("Acorn_Unthreaded/cap_reduced.stl"); |
| 85 | echo ("h = ", thread_height/scale_f); |
| 86 | cylinder (d = 180, h=thread_height/scale_f); |
| 87 | } |
| 88 | translate ([0, 0, -0.51]) cube ([200, 200, 1], center=true); |
| 89 | } |
| 90 | } |
| 91 | if (keychain) cap_keychain_holes (); |
| 92 | acorn_thread (internal = true, ring = false); |
| 93 | } |
| 94 | } |
| 95 | |
| 96 | module gasket (gasket_height=0.9) { |
| 97 | cylinder (d = outer_d, h = gasket_height, center=true); |
| 98 | } |
| 99 | |
| 100 | module nuts () { |
| 101 | translate ([outer_d+10, 0, 0,]) nut (); |
| 102 | cap (); |
| 103 | translate ([-(outer_d+10), 0, 0,]) gasket (); |
| 104 | } |
| 105 | |
| 106 | nuts (); |
| 107 | } |
| 108 | |
| 109 | $fs = 1; |
| 110 | $fa = 1; |
| 111 | |
| 112 | acorn (); |