Add latches to the lid

This commit is contained in:
2026-06-11 17:00:04 +02:00
parent dfed581377
commit cab17d08e9
4 changed files with 218 additions and 16 deletions
+166 -6
View File
@@ -1,9 +1,11 @@
// ============================================================
// Wargame Accessory Box & Dice Tray
// ------------------------------------------------------------
// Three printable parts:
// Printable parts:
// * box - open tray, doubles as a dice tray
// * lid - fully detachable friction-fit lid
// * lid - fully detachable lid, held shut by snap latches
// hinged on filament pins (or classic friction fit)
// * latch - one-piece snap latch (print 2 per latch position)
// * insert - removable compartment tray (configurable layout)
//
// Set `part` below (or via customizer / -D on the CLI) to
@@ -12,7 +14,7 @@
// ============================================================
/* [What to render] */
part = "assembly"; // [assembly, box, lid, insert, print]
part = "assembly"; // [assembly, box, lid, insert, latch, print]
/* [Outer dimensions (must fit the backpack)] */
// Total outer width (X), including walls
@@ -39,16 +41,39 @@ tray_chamfer = 6;
// Thickness of the flat lid plate
lid_top = 2.4;
// Height of the lip that plugs into the box opening
lip_h = 10;
lip_h = 5;
// Lip wall thickness
lip_t = 2.0;
// Gap per side between lip and box wall.
// Tune for your printer: smaller = tighter friction fit.
// With lid_style = "latch" the latches do the holding, so a
// looser 0.3 - 0.4 makes the lid easy to take off.
lid_clearance = 0.20;
// Thumb groove on the box's outer walls to pry the lid off
// (does NOT pierce the wall, dice tray stays closed)
// (friction lid only; latches replace it)
thumb_grooves = true;
/* [Latches] */
// How the lid is held shut. "latch": snap latches hinged on
// short pieces of filament (see README). "friction": original
// push fit.
lid_style = "latch"; // [latch, friction]
// Latches per long (front/back) wall, spread out evenly
latches_per_side = 2;
// Diameter of the filament used as hinge pin
filament_d = 1.75;
// Latch strip width
latch_w = 12;
// Latch strip thickness (thinner = softer snap)
latch_t = 2.0;
// Catch bar distance below the box rim
catch_drop = 14;
// Catch bar protrusion from the wall = snap engagement
catch_proud = 1.4;
// Vertical play between latch window and catch bar.
// Negative values preload the lid shut.
latch_play = 0.1;
/* [Insert] */
// Gap per side between insert and box wall
insert_clearance = 0.40;
@@ -103,6 +128,36 @@ ins_h = insert_h_override > 0
lip_x = inner_x - 2 * lid_clearance; // lid lip outer size
lip_y = inner_y - 2 * lid_clearance;
// --- latch hinge internals ---
lug_w = 5; // lid lug width (each side)
hinge_gap = 0.4; // side play lug <-> latch
pin_boss_r = filament_d / 2 + 2.3; // lug / barrel outer radius
pin_standoff = pin_boss_r + 0.4; // pin axis to wall face
lug_hole_d = filament_d + 0.15; // tight: pin glued into lugs
barrel_hole_d = filament_d + 0.35; // loose: latch pivots freely
latch_gap = 0.4; // latch strip to wall face
bar_h = 2.8; // catch bar height
bar_rise = 1.2; // straight part below chamfer
window_rail = 3; // strip rails beside window
window_w = latch_w - 2 * window_rail;
bar_len = window_w - 0.8;
grip_l = 6; // thumb flare below window
z_pin = box_h + lid_top - pin_boss_r; // hinge axis, lid closed
z_bar_top = box_h - catch_drop;
// latch window, measured down the strip from the pin axis
win_t1 = z_pin - z_bar_top - 0.4;
win_t2 = z_pin - z_bar_top + bar_h + latch_play;
latch_len = win_t2 + 4 + grip_l; // pin axis to latch tip
function latch_pos_x() =
latches_per_side <= 0 ? []
: [for (i = [1 : latches_per_side])
total_x * i / (latches_per_side + 1)];
assert(lid_style != "latch" || z_pin - latch_len > 2,
"box too shallow for the latch: reduce catch_drop");
// ------------------------------------------------------------
// Helpers
// ------------------------------------------------------------
@@ -141,7 +196,7 @@ module box() {
}
if (tray_chamfer > 0) tray_chamfers();
}
if (thumb_grooves)
if (thumb_grooves && lid_style == "friction")
for (m = [0, 1])
translate([total_x / 2,
m == 0 ? -(14 - groove_depth)
@@ -149,6 +204,25 @@ module box() {
box_h - 16])
cylinder(h = 20, d = 28, $fn = 48);
}
if (lid_style == "latch")
for (x0 = latch_pos_x()) {
translate([x0, 0, z_bar_top]) catch_bar();
translate([x0, total_y, z_bar_top])
mirror([0, 1, 0]) catch_bar();
}
}
// catch bar on the outer wall: origin on the wall face with the
// bar top at z = 0, protruding in -y. Chamfered on top so the
// latch rides over it, flat below so the latch can't cam out.
module catch_bar() {
translate([-bar_len / 2, 0, 0])
rotate([90, 0, 90])
linear_extrude(bar_len)
polygon([[0, 0],
[-catch_proud, -bar_h + bar_rise],
[-catch_proud, -bar_h],
[0, -bar_h]]);
}
module tray_chamfers() {
@@ -203,6 +277,77 @@ module lid() {
rbox(lip_x - 2 * lip_t, lip_y - 2 * lip_t,
lip_h + 1, max(inner_r - lip_t, 0.1));
}
if (lid_style == "latch")
for (x0 = latch_pos_x()) {
translate([x0, 0, 0]) lug_pair();
translate([x0, total_y, 0]) mirror([0, 1, 0]) lug_pair();
}
}
// ------------------------------------------------------------
// Latch hardware
// ------------------------------------------------------------
// One-piece snap latch hinged on a short piece of filament: the
// lid carries two lugs, the latch barrel sits between them, and
// the filament pin is glued into the (tighter) lug holes only,
// so the latch pivots freely. The window in the strip snaps
// over the catch bar on the box wall.
// one lid lug, centered on x = 0 at the lid edge y = 0, hanging
// outward in -y. Modeled in lid print orientation, so the pin
// boss rests flat on the bed.
module lid_lug() {
difference() {
hull() {
translate([-lug_w / 2, -pin_standoff, pin_boss_r])
rotate([0, 90, 0]) cylinder(r = pin_boss_r, h = lug_w);
translate([-lug_w / 2, 0, 0]) cube([lug_w, 2, lid_top]);
}
translate([-lug_w / 2 - 1, -pin_standoff, pin_boss_r])
rotate([0, 90, 0]) cylinder(d = lug_hole_d, h = lug_w + 2);
}
}
module lug_pair() {
off = latch_w / 2 + hinge_gap + lug_w / 2;
for (sx = [-1, 1]) translate([sx * off, 0, 0]) lid_lug();
}
// modeled flat: x = down the strip from the pin axis, y = away
// from the box wall, z = width. Prints standing on that flat
// face -> clean pivot hole and layer lines along the strip.
module latch() {
u0 = latch_gap; // inner face (toward the wall)
u1 = latch_gap + latch_t; // outer face
flare = 2.5;
difference() {
linear_extrude(latch_w) {
// pivot barrel
translate([0, pin_standoff]) circle(r = pin_boss_r);
polygon([
[0, u0],
[latch_len - 2, u0],
[latch_len, u0 + 1.4], // tip chamfer, rides
[latch_len, u1 + flare], // over the catch bar
[latch_len - 2, u1 + flare], // thumb flare to open
[win_t2 + 4, u1],
[0, u1]
]);
}
// pivot hole
translate([0, pin_standoff, -1])
cylinder(d = barrel_hole_d, h = latch_w + 2);
// window that snaps over the catch bar
translate([win_t1, -1, window_rail])
cube([win_t2 - win_t1, u1 + flare + 2, window_w]);
}
}
// latch in closed/engaged position on the front wall (y = 0)
module placed_latch(x0) {
translate([x0, 0, z_pin])
rotate([0, 0, 180]) rotate([0, 90, 0])
translate([0, 0, -latch_w / 2]) latch();
}
// ------------------------------------------------------------
@@ -263,14 +408,29 @@ module assembly() {
color("LightGreen", 0.7)
translate([0, total_y, box_h + ins_h + 25])
rotate([180, 0, 0]) translate([0, 0, -lid_top]) lid();
// latches hang from the floating lid's lugs
if (lid_style == "latch")
color("Tomato")
translate([0, 0, ins_h + 25])
for (x0 = latch_pos_x()) {
placed_latch(x0);
translate([0, total_y, 0])
mirror([0, 1, 0]) placed_latch(x0);
}
}
if (part == "box") box();
else if (part == "lid") lid();
else if (part == "insert") insert();
else if (part == "latch") latch();
else if (part == "print") {
box();
translate([total_x + 15, 0, 0]) lid();
translate([0, total_y + 15, 0]) insert();
if (lid_style == "latch" && latches_per_side > 0)
for (i = [0 : 2 * latches_per_side - 1])
translate([total_x + 15 + pin_boss_r,
total_y + 15 + i * (2 * pin_boss_r + 4), 0])
latch();
}
else assembly();