Plotter Pen Adapter for use with OpenJSCAD

plotter-pen-adapter.jscad

// title      : Plotter Pen Adapter
// author     : Brian Boucheron <brian@boucheron.org>
// license    : MIT License
// revision   : 0.003
// date       : June 9 2022
// file       : plotter-pen-adapter.jscad
// gist       : https://gist.github.com/beardicus/d668c0f6b96be53d16dc

// A parametric version of the plotter pen adapter found here:
// https://www.printables.com/model/156721-sharpie-fine-point-plotter-adapter
//
// This is designed to be loaded into OpenJSCAD by visiting the following URL:
// https://openjscad.xyz/#https://gist.githubusercontent.com/beardicus/d668c0f6b96be53d16dc/raw/plotter-pen-adapter.jscad
//
// The default parameters (in mm) are based on the Sharpie Fine Point pen,
// but can be tweaked for your particular pen, and are explained below. Enjoy,
// and get in touch with @bertmb and #plottertwitter
//
// Inner Diameter: this should be your pen's diameter, plus a little wiggle.
// You'll have to experiment for a good friction fit
//
// Outer Diameter: measured diameter of a real plotter pen is actually 11.5mm
// I bumped it for a thicker printable wall. There's probably some wiggle room.
//
// Barrel Length: how long of a barrel or "sleeve" do you want?
//
// Ring Height: height to bottom of the retaining ring (NOT midline)

// import giblets
const { cylinder, polygon } = require('@jscad/modeling').primitives
const { union, subtract } = require('@jscad/modeling').booleans
const { extrudeRotate } = require('@jscad/modeling').extrusions
const { translateZ } = require('@jscad/modeling').transforms

// build a profile for the retaining ring
const ring_thickness = 2.0 // thickest point of the ring
const ring_edge_thickness = 0.6 // thickness at the very edge of the ring
const ring_diameter = 16.5 // diameter of the ring
const ring_edge_diameter = 15.0 // diameter where ring starts to bevel

const profile = [
  [1, 0],
  [ring_edge_diameter / 2, 0],
  [ring_diameter / 2, (ring_thickness - ring_edge_thickness) / 2],
  [
    ring_diameter / 2,
    ring_thickness - (ring_thickness - ring_edge_thickness) / 2,
  ],
  [ring_edge_diameter / 2, ring_thickness],
  [1, ring_thickness],
]

// get parameters
const getParameterDefinitions = () => [
  {
    name: 'penDiameter',
    type: 'number',
    initial: 10.8,
    caption: 'Inner Diamter',
  },
  {
    name: 'adapterDiamter',
    type: 'number',
    initial: 11.6,
    caption: 'Outer Diameter',
  },
  {
    name: 'barrelLength',
    type: 'number',
    initial: 20.7,
    caption: 'Barrel Length',
  },
  {
    name: 'ringHeight',
    type: 'number',
    initial: 11,
    caption: 'Ring Height',
  },
]

// FIRE THE SPATIAL GEOMETRON
const main = (params) => {
  // make the ring and main body shapes
  const ring = extrudeRotate({ segments: 50 }, polygon({ points: profile }))
  const body = cylinder({
    radius: params.adapterDiamter / 2,
    height: params.barrelLength,
    center: [0, 0, params.barrelLength / 2],
    segments: 50,
  })

  // combine the ring and body at the appropriate ringHeight
  const unibody = union(body, translateZ(params.ringHeight, ring))

  // make the hole shape
  const hole = cylinder({
    radius: params.penDiameter / 2,
    height: 50,
    segments: 50,
    center: [0, 0, 24],
  })

  // return the holed body
  return subtract(unibody, hole)
}

module.exports = { main, getParameterDefinitions }