OpenSCAD source code: Badge lanyard reel mount

Badge Lanyard Reel Mount.scad

// Badge Lanyard Reel Mount
// Ed Nisley KE4ZNU April 2017
// Reel center at origin, lanyard exit toward +X

Layout = "Show";

Support = true;

//- Extrusion parameters must match reality!

ThreadThick = 0.20;
ThreadWidth = 0.40;

HoleWindage = 0.2;

Protrusion = 0.05;      // make holes end cleanly

inch = 25.4;

function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

//----------------------
// Dimensions

ID = 0;                      // for round things
OD = 1;
LENGTH = 2;

Carabiner = [30.7,35.3,3.5];      // metal carabiner around original reel
Latch = [6.0,-15,8.0];            // wire spring latch: offset from OD + thickness
LatchAngle = 60;                  // max deflection angle to center from -X direction

LatchPoints = [[0,0],
               [Latch[1]/tan(LatchAngle),0],
               [Latch[1]/tan(LatchAngle),-Latch[1]]];    // polygon in as-cut orientation

echo(str("Latch polygon: ",LatchPoints));

Screw = [2.0,3.8 + 0*ThreadWidth,10.0];           // M2 screw: ID = clear, OD = head
ScrewHeadLength = 2.0;
ScrewSides = 8;
ScrewRecess = 5*ThreadThick;

MountSides = ScrewSides;                   // suitably gritty corners

MountThick = Screw[LENGTH] / cos(180/MountSides) + ScrewRecess + 2.0;

Insert = [Screw[ID],3.4,4.0];     // brass insert for screws

BCD = Carabiner[OD] + 2.5*Insert[OD];

BoltAngles = [20,110];            // ± angles to bolt holes

Reel = [5.3,25.5 + 2*ThreadWidth,6.0 + 2*ThreadThick];            // lanyard cord reel
ShimThick = 2*ThreadThick;        // covers open side of reel for better sliding

Bezel = [31.0,32.0,7.5];          // PCB holder + shell, LENGTH = post + shell
BezelSides = 6*4;
BezelBlock = [5.5,7.5,3.6] + [ThreadWidth,ThreadWidth,ThreadThick];       // block around lanyard eyelet

Eyelet = [3.5,4.5,3.0];

Bullet = [2.0,6.5,2.0];           // brass badge holder, LENGTH = recess into mount

//----------------------
// Useful routines

module PolyCyl(Dia,Height,ForceSides=0) {      // based on nophead's polyholes

  Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);

  FixDia = Dia / cos(180/Sides);

  cylinder(r=(FixDia + HoleWindage)/2,
    h=Height,
  $fn=Sides);
}

//-- Lanyard reel mockup

module Reel() {

  cylinder(d=Reel[OD],h=Reel[LENGTH],center=true,$fn=6*4);

}

// Carabiner metal mockup
// Some magic numbers lie in wait

module Beener() {

  difference() {
    hull() {
      cylinder(d=Carabiner[OD],
               h=Carabiner[LENGTH] + 2*ThreadThick,
               center=true,$fn=BezelSides);
      translate([-Carabiner[OD]/2,0,0])
        cylinder(d=Carabiner[OD] - 2.0,
                 h=Carabiner[LENGTH] + 2*ThreadThick,
                 center=true,$fn=6*4);
    }
    cylinder(d=Carabiner[ID],
             h=2*Carabiner[LENGTH],
             center=true,$fn=BezelSides);
    translate([Carabiner[ID]/4,0,0])
      cube([Carabiner[ID],7.0,2*Carabiner[LENGTH]],center=true);
  }
}

// mockup of PCB holder atop remains of old mount with reel post
// Z = 0 at midline of case

module BezelMount() {

  rotate(180/BezelSides) {
    PolyCyl(Bezel[ID] + HoleWindage,MountThick,BezelSides);               // PCB punches through mount
    PolyCyl(Bezel[OD] + HoleWindage,Bezel[LENGTH] - Reel[LENGTH]/2,BezelSides);
  }

  translate([Reel[OD]/2,0,BezelBlock[2]/2])
    scale([2,1,1])
      cube(BezelBlock,center=true);
}

// Main mount around holder & carabiner

module Mount(Section="All") {

  render()
  difference() {
    hull() {
      for (a = BoltAngles)                          // spheres defining corners
        for (i=[-1,1])
          rotate(i*a)
            translate([BCD/2,0,0])
              sphere(d=MountThick,$fn=MountSides);
      cylinder(d=Carabiner[OD] + 4*ThreadWidth,
               h=MountThick,center=true);   // capture carabiner ring
    }

    for (a = BoltAngles)                    // screw & insert holes, head recess
      for (i=[-1,1])
        rotate(i*a)
          translate([BCD/2,0,0])
            rotate(0*i*180/ScrewSides) {
              translate([0,0,-(Insert[LENGTH] + 2*ThreadThick)])
                PolyCyl(Insert[OD],
                        Insert[LENGTH] + 2*ThreadThick + Protrusion,ScrewSides);
              for (k = [-2:2])              // epoxy retaining grooves
                translate([0,0,-(k*3*ThreadThick + Insert[LENGTH]/2)])
                  PolyCyl(Insert[OD] + 1*ThreadWidth,
                          2*ThreadThick,ScrewSides);
              PolyCyl(Screw[ID],Screw[LENGTH],ScrewSides);
              translate([0,0,MountThick/2 - ScrewRecess])    // recess screw heads
                PolyCyl(Screw[OD],Screw[LENGTH],ScrewSides);
              }

    translate([0,0,-1*ThreadThick])           // Minkowski Z extends only top surface!
      minkowski() {                                     // space for metal carabiner
        Beener();
//        cube([ThreadWidth,ThreadWidth,2*ThreadThick]);
        cylinder(d=ThreadWidth,h=2*ThreadThick,$fn=6);
      }

    rotate([0,90,0]) rotate(180/6)                    // cord channel = brass tube clearance
      PolyCyl(Bullet[ID],Carabiner[ID],6);

    translate([Eyelet[LENGTH] + 2.0,0,0])             // eyelet, large end inward
      rotate([0,90,0]) rotate(180/6)
        PolyCyl(Eyelet[OD] + HoleWindage, Reel[OD]/2,6);

    if (false)
      translate([Reel[OD]/2 + Eyelet[LENGTH]/2,0,0])    // eyelet, small end outward
        rotate([0,90,0]) rotate(180/6)
          PolyCyl(Eyelet[ID],Eyelet[LENGTH],6);

    translate([(BCD/2 + MountThick/2)*cos(BoltAngles[0]) - Bullet[LENGTH],0,0])    // bullet recess
      rotate([0,90,0]) rotate(180/6)
        PolyCyl(Bullet[OD],Carabiner[ID],6);

    BezelMount();                                     // PCB holder clearance

    Reel();                                           // reel clearance

    translate([0,0,-(Reel[LENGTH] + ShimThick)/2])    // sliding plate on open side of reel
      cylinder(d=Reel[OD],h=ShimThick,center=true,$fn=6*4);

    translate([-Carabiner[OD]/2 + Latch[0],Latch[1],0])
      linear_extrude(height=Latch[2],center=true)
        polygon(LatchPoints);

    if (Section == "Upper")                           // display & build section cutting
      translate([0,0,-2*Carabiner[LENGTH]])
        cube(4*Carabiner,center=true);
    else if (Section == "Lower")
      translate([0,0,2*Carabiner[LENGTH]])
        cube(4*Carabiner,center=true);

  }

  if (Support) {                                      // Completely ad-hoc support structures
    color("Yellow", Layout == "Show" ? 0.3 : 1.0) {
      if (false && Section == "Upper") {
        Spokes = BezelSides;
        Offset = 6*ThreadWidth;
        for (i = [2:Spokes - 2])
          rotate(i * 360/Spokes)
            translate([Offset,-ThreadWidth,0*(Carabiner[LENGTH]/2)/2])
              cube([Carabiner[OD]/2 - Offset - 0*ThreadWidth,
                    2*ThreadWidth,
                    Carabiner[LENGTH]/2],center=false);
        for (i = [0:Spokes - 1])
          rotate(i * 360/Spokes)
            translate([Offset,-ThreadWidth,0])
              cube([Bezel[OD]/2 - Offset,
                    2*ThreadWidth,
                    Bezel[LENGTH] - Reel[LENGTH]/2 - 2*ThreadThick],center=false);
        Bars = 7;
        render()
          difference() {
            union() {
            for (i = [-floor(Bars/2) : floor(Bars/2)])
              translate([-Carabiner[ID]/2,i*Carabiner[OD]/Bars,Carabiner[LENGTH]/4])
                cube([Carabiner[ID]/3,2*ThreadWidth,Carabiner[LENGTH]/2],center=true);
              translate([-Carabiner[ID]/2,0,ThreadThick/2])
                cube([Carabiner[ID]/3,Carabiner[ID],ThreadThick],center=true);
            }
            cylinder(d=Carabiner[ID] + 2*ThreadWidth,h=Carabiner[LENGTH]);
          }
      }
      if (Section == "Lower") {
        translate([0,0,-(Reel[LENGTH]/4 + ShimThick/2 - ThreadThick/2)])
          for (i = [0:8])
            rotate(i * 360/8)
              cube([Reel[OD] - 2*ThreadWidth,
                   2*ThreadWidth,
                   Reel[LENGTH]/2 + ShimThick - ThreadThick],center=true);
        if (false) {
          Bars = 7;
          render()
            difference() {
              union() {
              for (i = [-floor(Bars/2) : floor(Bars/2)])
                translate([-Carabiner[ID]/2,i*Carabiner[OD]/Bars,-Carabiner[LENGTH]/4])
                  cube([Carabiner[ID]/3,2*ThreadWidth,Carabiner[LENGTH]/2],center=true);
                translate([-Carabiner[ID]/2,0,-ThreadThick/2])
                  cube([Carabiner[ID]/3,Carabiner[ID],ThreadThick],center=true);
              }
              translate([0,0,-Carabiner[LENGTH]])
                cylinder(d=Carabiner[ID] + 0*ThreadWidth,h=Carabiner[LENGTH]);
            }
        }
      }
    }
  }

}



//----------------------
// Build it

if (Layout == "Beener")
  Beener();

if (Layout == "Mount")
  Mount();

if (Layout == "Reel")
  Reel();

if (Layout == "BezelMount")
  BezelMount();

Gap = 25;
if (Layout == "Show") {
  translate([0,0,Gap/2])
    Mount("Upper");
  translate([0,0,-Gap/2])
    Mount("Lower");
  color("Green",0.3)
    Beener();
  color("Brown",0.3)
    Reel();
  color("Red",0.3)
    translate([0,0,-(Reel[LENGTH] + ShimThick)/2])
      cylinder(d=Reel[OD],h=ShimThick,center=true,$fn=6*4);
}

if (Layout == "Build") {
  translate([(BCD + MountThick)/2,0,0])
    rotate(180)
      Mount("Upper");
  rotate([180,0,0])
    translate([-(BCD + MountThick)/2,0,0])
      Mount("Lower");
}

if (Layout == "BuildUpper")
  Mount("Upper");

if (Layout == "BuildLower")
  rotate([180,0,0])
    Mount("Lower");

More detail on my blog at http://wp.me/poZKh-6HR