| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * A spacer for the Sparrows disc-detainer picking tool |
| 4 | * |
| 5 | * (c) 2022 Mark Wooding |
| 6 | */ |
| 7 | |
| 8 | /*----- Licensing notice --------------------------------------------------* |
| 9 | * |
| 10 | * This program is free software: you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation; either version 3 of the License, or (at |
| 13 | * your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, but |
| 16 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program. If not, see <https://www.gnu.org/licenses/>. |
| 22 | */ |
| 23 | |
| 24 | /*----- Configuration -----------------------------------------------------*/ |
| 25 | |
| 26 | /* Overall scaling. */ |
| 27 | MM = 1; |
| 28 | |
| 29 | /* Curvature quality. */ |
| 30 | $fa = 0.1; |
| 31 | $fs = 0.2*MM; |
| 32 | |
| 33 | /* A `large enough' length; effectively infinite. */ |
| 34 | BIG = 20*MM; |
| 35 | |
| 36 | /* Dimensions. */ |
| 37 | CUT_WD = 10*MM; /* width of the cut in the top */ |
| 38 | BORE_DIAM = 6*MM; /* diameter of hole down the mid */ |
| 39 | SPACER_HT = 7.25*MM; /* height of the offset */ |
| 40 | HEIGHT = SPACER_HT + 3*MM; /* overall ht, including shelves */ |
| 41 | THICK = 16*MM; /* thickness */ |
| 42 | WIDTH = 18*MM; /* width */ |
| 43 | |
| 44 | /*----- The main object ---------------------------------------------------*/ |
| 45 | |
| 46 | difference() { |
| 47 | intersection() { |
| 48 | |
| 49 | /* Start with a bounding parallelepiped. We're going to shave pieces of |
| 50 | * this to make the actual object. |
| 51 | */ |
| 52 | translate([-WIDTH/2, -THICK/2, 0]) |
| 53 | cube([WIDTH, THICK, HEIGHT]); |
| 54 | |
| 55 | /* Round off the vertical edges. */ |
| 56 | cylinder(h = HEIGHT, r = norm([CUT_WD/2, WIDTH/2])); |
| 57 | |
| 58 | /* Round off the shelves that sit around the pick body. */ |
| 59 | rotate([0, 90, 0]) |
| 60 | translate([0, 0, -BIG/2]) |
| 61 | cylinder(h = BIG, r = norm([HEIGHT, CUT_WD/2])); |
| 62 | } |
| 63 | |
| 64 | union() { |
| 65 | |
| 66 | /* Cut out the channel in which the pick body sits, leaving the shelves |
| 67 | * on either side. |
| 68 | */ |
| 69 | translate([-BIG/2, -CUT_WD/2, SPACER_HT]) |
| 70 | cube([BIG, CUT_WD, BIG]); |
| 71 | |
| 72 | /* Bore the hole down the middle through which the tensioning prongs and |
| 73 | * pick fit. |
| 74 | */ |
| 75 | translate([0, 0, -BIG/3]) |
| 76 | cylinder(h = BIG, r = BORE_DIAM/2); |
| 77 | } |
| 78 | } |
| 79 | |
| 80 | /*----- That's all, folks -------------------------------------------------*/ |