gridfinity-rebuilt-openscad/gridfinity-rebuilt-holes.scad
2024-08-29 20:14:51 -04:00

334 lines
12 KiB
OpenSCAD

/**
* @file gridfinity-rebuilt-holes.scad
* @brief Functions to create different types of holes in an object.
*/
include <standard.scad>
use <generic-helpers.scad>
/**
* @brief Determines the number of fragments in a circle. Aka, Circle resolution.
* @param r Radius of the circle.
* @details Recommended function from the manual as a translation of the OpenSCAD function.
* Used to improve performance by not rendering every single degree of circles/spheres.
* @see https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Other_Language_Features#Circle_resolution:_$fa,_$fs,_and_$fn
*/
function get_fragments_from_r(r) =
assert(r > 0)
($fn>0?($fn>=3?$fn:3):ceil(max(min(360/$fa,r*2*PI/$fs),5)));
/**
* @brief Wave generation function for wrapping a circle.
* @param t An angle of the circle. Between 0 and 360 degrees.
* @param count The number of **full** waves in a 360 degree circle.
* @param range **Half** the difference between minimum and maximum values.
* @param vertical_offset Added to the output.
* When wrapping a circle, radius of that circle.
* @details
* If plotted on an x/y graph this produces a standard sin wave.
* Range only seems weird because it describes half a wave.
* Mapped by doing [sin(t), cost(t)] * wave_function(...).
* When wrapping a circle:
* Final Outer radius is (wave_vertical_offset + wave_range).
* Final Inner radius is (wave_vertical_offset - wave_range).
*/
function wave_function(t, count, range, vertical_offset) =
(sin(t * count) * range) + vertical_offset;
/**
* @brief A circle with crush ribs to give a tighter press fit.
* @details Extrude and use as a negative modifier.
* Idea based on Slant3D's video at 5:20 https://youtu.be/Bd7Yyn61XWQ?t=320
* Implementaiton is completely different.
* Important: Lower ribs numbers just result in a deformed circle.
* @param outer_radius Final outer radius.
* @param inner_radius Final inner radius.
* @param ribs Number of crush ribs the circle has.
**/
module ribbed_circle(outer_radius, inner_radius, ribs) {
assert(outer_radius > 0, "outer_radius must be positive");
assert(inner_radius > 0, "inner_radius must be positive");
assert(ribs > 0, "ribs must be positive");
assert(outer_radius > inner_radius, "outer_radius must be larger than inner_radius");
wave_range = (outer_radius - inner_radius) / 2;
wave_vertical_offset = inner_radius + wave_range;
fragments=get_fragments_from_r(wave_vertical_offset);
degrees_per_fragment = 360/fragments;
// Circe with a wave wrapped around it
wrapped_circle = [ for (i = [0:degrees_per_fragment:360])
[sin(i), cos(i)] * wave_function(i, ribs, wave_range, wave_vertical_offset)
];
polygon(wrapped_circle);
}
/**
* @brief A cylinder with crush ribs to give a tighter press fit.
* @details To be used as the negative for a hole.
* @see ribbed_circle
* @param outer_radius Outer Radius of the crush ribs.
* @param inner_radius Inner Radius of the crush ribs.
* @param height Cylinder's height.
* @param ribs Number of crush ribs.
*/
module ribbed_cylinder(outer_radius, inner_radius, height, ribs) {
assert(height > 0, "height must be positive");
linear_extrude(height)
ribbed_circle(
outer_radius,
inner_radius,
ribs
);
}
/**
* @brief Make a hole printable without suports.
* @see https://www.youtube.com/watch?v=W8FbHTcB05w
* @param inner_radius Radius of the inner hole.
* @param outer_radius Radius of the outer hole.
* @param outer_height Height of the outer hole.
* @param layers Number of layers to make printable.
* @details This is the negative designed to be cut out of the magnet hole.
* Use it with `difference()`.
* Special handling is done to support a single layer,
* and because the last layer (unless there is only one) has a different shape.
*/
module make_hole_printable(inner_radius, outer_radius, outer_height, layers=2) {
assert(inner_radius > 0, "inner_radius must be positive");
assert(outer_radius > 0, "outer_radius must be positive");
assert(layers > 0);
tollerance = 0.01; // Ensure everything is fully removed.
height_adjustment = outer_height - (layers * LAYER_HEIGHT);
// Needed, since the last layer should not be used for calculations,
// unless there is a single layer.
calculation_layers = max(layers-1, 1);
cube_height = LAYER_HEIGHT + 2*tollerance;
inner_diameter = 2*(inner_radius+tollerance);
outer_diameter = 2*(outer_radius+tollerance);
per_layer_difference = (outer_diameter-inner_diameter) / calculation_layers;
initial_matrix = affine_translate([0, 0, cube_height/2-tollerance + height_adjustment]);
// Produces data in the form [affine_matrix, [cube_dimensions]]
// If layers > 1, the last item produced has an invalid "affine_matrix.y", because it is beyond calculation_layers.
// That is handled in a special case to avoid doing a check every loop.
cutout_information = [
for(i=0; i <= layers; i=i+1)
[
initial_matrix * affine_translate([0, 0, (i-1)*LAYER_HEIGHT]) *
affine_rotate([0, 0, is_even(i) ? 90 : 0]),
[outer_diameter-per_layer_difference*(i-1),
outer_diameter-per_layer_difference*i,
cube_height]
]
];
difference() {
translate([0, 0, layers*cube_height/2 + height_adjustment])
cube([outer_diameter+tollerance, outer_diameter+tollerance, layers*cube_height], center = true);
for (i = [1 : calculation_layers]){
data = cutout_information[i];
multmatrix(data[0])
cube(data[1], center = true);
}
if(layers > 1) {
data = cutout_information[len(cutout_information)-1];
multmatrix(data[0])
cube([data[1].x, data[1].x, data[1].z], center = true);
}
}
}
/**
* @brief Refined hole based on Printables @grizzie17's Gridfinity Refined
* @details Magnet is pushed in from +X direction, and held in by friction.
* Small slit on the bottom allows removing the magnet.
* @see https://www.printables.com/model/413761-gridfinity-refined
*/
module refined_hole() {
refined_offset = LAYER_HEIGHT * REFINED_HOLE_BOTTOM_LAYERS;
// Poke through - For removing a magnet using a toothpick
ptl = refined_offset + LAYER_HEIGHT; // Additional layer just in case
poke_through_height = REFINED_HOLE_HEIGHT + ptl;
poke_hole_radius = 2.5;
magic_constant = 5.60;
poke_hole_center = [-12.53 + magic_constant, 0, -ptl];
translate([0, 0, refined_offset])
union() {
// Magnet hole
translate([0, -REFINED_HOLE_RADIUS, 0])
cube([11, REFINED_HOLE_RADIUS*2, REFINED_HOLE_HEIGHT]);
cylinder(REFINED_HOLE_HEIGHT, r=REFINED_HOLE_RADIUS);
// Poke hole
translate([poke_hole_center.x, -poke_hole_radius/2, poke_hole_center.z])
cube([10 - magic_constant, poke_hole_radius, poke_through_height]);
translate(poke_hole_center)
cylinder(poke_through_height, d=poke_hole_radius);
}
}
/**
* @brief Create a cone given a radius and an angle.
* @param bottom_radius Radius of the bottom of the cone.
* @param angle Angle as measured from the bottom of the cone.
* @param max_height Optional maximum height. Cone will be cut off if higher.
*/
module cone(bottom_radius, angle, max_height=0) {
assert(bottom_radius > 0);
assert(angle > 0 && angle <= 90);
assert(max_height >=0);
height = tan(angle) * bottom_radius;
if(max_height == 0 || height < max_height) {
// Normal Cone
cylinder(h = height, r1 = bottom_radius, r2 = 0, center = false);
} else {
top_angle = 90 - angle;
top_radius = bottom_radius - tan(top_angle) * max_height;
cylinder(h = max_height, r1 = bottom_radius, r2 = top_radius, center = false);
}
}
/**
* @brief Create a screw hole
* @param radius Radius of the hole.
* @param height Height of the hole.
* @param supportless If the hole is designed to be printed without supports.
* @param chamfer_radius If the hole should be chamfered, then how much should be added to radius. 0 means don't chamfer
* @param chamfer_angle If the hole should be chamfered, then what angle should it be chamfered at. Ignored if chamfer_radius is 0.
*/
module screw_hole(radius, height, supportless=false, chamfer_radius=0, chamfer_angle = 45) {
assert(radius > 0);
assert(height > 0);
assert(chamfer_radius >= 0);
union(){
difference() {
cylinder(h = height, r = radius);
if (supportless) {
rotate([0, 0, 90])
make_hole_printable(0.5, radius, height, 3);
}
}
if (chamfer_radius > 0) {
cone(radius + chamfer_radius, chamfer_angle, height);
}
}
}
/**
* @brief Create an options list used to configure bin holes.
* @param refined_hole Use gridfinity refined hole type. Not compatible with "magnet_hole".
* @param magnet_hole Create a hole for a 6mm magnet.
* @param screw_hole Create a hole for a M3 screw.
* @param crush_ribs If the magnet hole should have crush ribs for a press fit.
* @param chamfer Add a chamfer to the magnet/screw hole.
* @param supportless If the magnet/screw hole should be printed in such a way that the screw hole does not require supports.
*/
function bundle_hole_options(refined_hole=false, magnet_hole=false, screw_hole=false, crush_ribs=false, chamfer=false, supportless=false) =
assert(
is_bool(refined_hole) &&
is_bool(magnet_hole) &&
is_bool(screw_hole) &&
is_bool(crush_ribs) &&
is_bool(chamfer) &&
is_bool(supportless))
[refined_hole, magnet_hole, screw_hole, crush_ribs, chamfer, supportless];
/**
* @summary Ensures that hole options are valid, and can be used.
*/
module assert_hole_options_valid(hole_options) {
assert(is_list(hole_options) && len(hole_options) == 6);
for(option=hole_options){
assert(is_bool(option), "One or more hole options is not a boolean value!");
}
refined_hole = hole_options[0];
magnet_hole = hole_options[1];
if(refined_hole) {
assert(!magnet_hole, "magnet_hole is not compatible with refined_hole");
}
}
/**
* @brief A single magnet/screw hole. To be cut out of the base.
* @details Supports multiple options that can be mixed and matched.
* @pram hole_options @see bundle_hole_options
* @param o Offset
*/
module block_base_hole(hole_options, o=0) {
assert_hole_options_valid(hole_options);
assert(is_num(o));
// Destructure the options
refined_hole = hole_options[0];
magnet_hole = hole_options[1];
screw_hole = hole_options[2];
crush_ribs = hole_options[3];
chamfer = hole_options[4];
supportless = hole_options[5];
screw_radius = SCREW_HOLE_RADIUS - (o/2);
magnet_radius = MAGNET_HOLE_RADIUS - (o/2);
magnet_inner_radius = MAGNET_HOLE_CRUSH_RIB_INNER_RADIUS - (o/2);
screw_depth = h_base-o;
// If using supportless / printable mode, need to add additional layers, so they can be removed later.
supportless_additional_layers = screw_hole ? 2 : 3;
magnet_depth = MAGNET_HOLE_DEPTH - o +
(supportless ? supportless_additional_layers*LAYER_HEIGHT : 0);
union() {
if(refined_hole) {
refined_hole();
}
if(magnet_hole) {
difference() {
if(crush_ribs) {
ribbed_cylinder(magnet_radius, magnet_inner_radius, magnet_depth, MAGNET_HOLE_CRUSH_RIB_COUNT);
} else {
cylinder(h = magnet_depth, r=magnet_radius);
}
if(supportless) {
make_hole_printable(
screw_hole ? screw_radius : 1, magnet_radius, magnet_depth, supportless_additional_layers);
}
}
if(chamfer) {
cone(magnet_radius + CHAMFER_ADDITIONAL_RADIUS, CHAMFER_ANGLE, MAGNET_HOLE_DEPTH - o);
}
}
if(screw_hole) {
screw_hole(screw_radius, screw_depth, supportless,
chamfer ? CHAMFER_ADDITIONAL_RADIUS : 0, CHAMFER_ANGLE);
}
}
}
//$fa = 8;
//$fs = 0.25;
if(!is_undef(test_options)){
block_base_hole(test_options);
}
//block_base_hole(bundle_hole_options(
// refined_hole=false,
// magnet_hole=true,
// screw_hole=true,
// supportless=true,
// crush_ribs=false,
// chamfer=true
//));
//make_hole_printable(1, 3, 0);