kreyren / openscad-pegboard-peggrid Goto Github PK

OpenSCAD library to generate various parametric pegboard-like shapes, i.e. perforated rectangles.

See Thingiverse for previews, examples, etc. Customiser enabled, but really, it's not at all hard to just use OpenSCAD for the job.

Basic Usage

Download pegboard.scad and put it in the same directory as your project, then:

use <pegboard.scad>

board_dimensions = [30, 30, 3]; // 30mm x 30mm rectangle, 3mm thick
hole_diameter = 3; // 3mm holes
hole_pitch = 6; // hole centers 6mm apart

pegboard(board_dimensions, hole_diameter, hole_pitch);

(It's better to put it on the OpenSCAD library path rather than putting it in your project directory, but that'll get you started).

Modules:

• pegboard: produces a rectangular board with peg holes.

  Holes may optionally be less than full depth, and peg pattern may optionally be a square grid instead of the hexagonally packed default arrangement. Pitch, peg diameter and edge margins with no pegs are all customisable.

  pegboard(dims, hole_diameter, hole_pitch) pegboard(dims, hole_diameter, hole_pitch, hexpattern, margins, center, hole_depth)

• peg_grid: produces a rectangular arrangement of cylindrical pegs, i.e. a negative pegboard. Used to subtract from other objects. You can clip it etc too.

  peg_grid(dims, peg_diameter, peg_pitch) peg_grid(dims, peg_diameter, peg_pitch, hexpattern, margins, center)

Parameters

All parameters may be passed as positional parameters or by name.

All dimensional units are millimeters.

• dims (3-vector of +number, required):

  Vector [x,y,z] of dimensions of the pegboard, or in the case of the peg grid, the outer bounds within which the grid should be laid out. Positive number.

  For peg_grid the z-dimension is the peg length; for pegboard it's the board thickness and the holes default to fully punching through both sides of the board. Internally some slop is added when subtracting the pegs to ensure there are no floating point artifacts here.

• hole_diameter / peg_diameter (+number, required):

  Diameter of the pegs/holes.

  Remember printer tolerances, print some tests for fit before you do a big print run, or print with extra wall thickness and be prepared to do some filing/drilling. Consider whether you're going for a friction fit or free movement too.

  TODO: support non-cylindrical pegs/holes: basic shapes, cylinders with friction grip knobs, and children() for arbitrary holes.

• hole_pitch / peg_pitch (+number, required):

  Center-to-center spacing of the pegs/holes. The solid space between holes (the bridge size) will be hole_pitch - hole_diameter. If set the same as hole_diameter, pegs/holes will touch. If less than hole_diameter the pegs/holes will intersect each other. See examples in test suite.

  A sensible initial choice can be hole_diameter * 2, which makes the spaces between pegs (bridges between holes) the same size as the pegs themselves.

• hexpattern (boolean, optional):

  Arrange the pegs/holes in a tighter packed hexagonal pattern where every second row's pegs are horizontally offset by hole_pitch/2 from the pegs on the adjacent rows. This yields a stronger shape because the pattern is now tesselated triangles instead of squares. also gives more options for positioning things in the holes.

  hexpattern breaks y-symmetry if an even number of rows are produced.

  Default: true

• margins (number or 2-vector of number, optional):

  Margins around the edges of the board where no holes should be placed. Can be a 2-vector [x,y] or a scalar. Zero margins makes the hole edges touch the edge of the square defined by dims so it's the default for peg_grid, while peg_board defaults to a hole radius worth of margin.

  If center=true and the hole pitch/diameter doesn't cause the holes to fully pack the available space, actual effective will be slightly larger because the hole grid will get centered.

  Default: peg_diameter/2 for pegboard, 0 for peg_grid.

• center (boolean, optional):

  Arrange the holes / peg grid within the supplied x/y dims bounds so that any extra space not filled by the peg grid is equal on both sides, i.e. the peg grid is centered. This enables you to safely mirror the peg grid across the y axis (flip horizontally) and have the holes in the mirrored pieces line up. It'll be vertically symmetrical too unless it's a hex pattern grid with an even number of rows.

  Default: true

Examples

See the basic test suite in pegboard_test.scad for examples.

beam_margins = hole_pitch/2;

See pegboard.scad, its tests and its examples for all the things you can do with it.

License and derivatives

This library is BSD licensed. The license specifies what you can do with it, and nothing in the following restricts the permissions granted by the license.

I have a few requests that I would appreciate you following, though the license does not require you to do so:

1. Please do not create derivatives of this library on Thingiverse or elsewhere without linking to the original. I would prefer that you submit changes to me for inclusion in the main library instead, if you can make them work without breaking the existing tests.
2. Credit me as original author if you publish derivatives. Feel free to credit me for the bugs too ;) .

Testing

To test changes you make to the library, enable the run_tests parameter in the file. It'll produce a set of tests. There are a few assertions in there for basic functionality, but OpenSCAD doesn't make it easy to write useful tests since it lacks the ability to introspect objects usefully. So you have to eyeball it and compare the described expected results to what you see on the test pattern. A sample test result .stl and .png is included.

TODO

At some stage I may be motivated to:

• Support non-rectangular shapes
• Support non-cylindrical holes
• Use OpenSCAD's children() to let you define your own arbitrary hole modules

... none of which is hard, so if you want it, ask me for advice and I'll point you in the right direction.

Code contributions appreciated.