The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Tour Easy Daytime Running Light: Now with Chirality!

    In the unlikely event our bikes need two running lights or, perhaps, a running light and a headlight, the solid model now builds mounts for the right side of the fairing, as before:

    Fairing Flashlight Mount - Right side - solid model
    Fairing Flashlight Mount – Right side – solid model

    And for the left side:

    Fairing Flashlight Mount - Left side - solid model
    Fairing Flashlight Mount – Left side – solid model

    Ahhh, chirality: love that word.

    Those pix come from a cleaned-up version of the OpenSCAD code that finally gets the 3-axis rotations right, after a rip-and-replace rewrite to deliver the ball model with its origin in the center of the ball where it belonged and rotate the ring about its geometric center. Then the rotations become trivially easy and a slight hack job spits out a completely assembled model:

    if (Component == "Complete") {
      translate([-BracketHoleOC,0,0])
        PlateBlank();
      mirror(TiltMirror) {
        translate([0,0,ClampOD/2]) {
          rotate([-Roll,ToeIn,Tilt])
            SlotBall();
          rotate([-Roll,ToeIn,Tilt])
            BallClamp();
        }
      }
    }
    

    However, putting the center of rotation directly over the center of the base plate means the ToeIn rotation shifts the bottom of the clamp ring along the X axis, where it can obstruct the mounting holes. Shifting the ring by a little bit:

    ClampOD*sin(ToeIn/2)

    … keeps the ring more-or-less centered on the top of the plate. That’s not quite the correct geometry, but it’s close enough for the small angles needed here.

    Aiming the beam slightly higher makes a 400 lumen flashlight about as bright as any single LED in new car running lights:

    Fairing Flashlight Mount - Mary approaching
    Fairing Flashlight Mount – Mary approaching

    You can just barely make out the snazzy new blue plate on the left side of the fairing.

    A bike’s natural back-and-forth handlebar motion sweeps the beam across the lane, so I think there’s no real benefit from blinking.

    The OpenSCAD source code as a GitHub Gist:

    // Tour Easy Fairing Flashlight Mount
    // Ed Nisley KE4ZNU – July 2017
    // August 2017 –
    /* [Build Options] */
    FlashName = "AnkerLC40"; // [AnkerLC40,AnkerLC90,J5TactV2,InnovaX5]
    Component = "Complete"; // [Ball, BallClamp, Mount, Plates, Bracket, Complete]
    Layout = "Show"; // [Build, Show]
    Support = false;
    MountSupport = false;
    /* [Extrusion] */
    ThreadThick = 0.25; // [0.20, 0.25]
    ThreadWidth = 0.40; // [0.40]
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    Protrusion = 0.01; // [0.01, 0.1]
    HoleWindage = 0.2;
    /* [Fairing Mount] */
    Side = "Right"; // [Right,Left]
    ToeIn = 0; // inward from ahead
    Tilt = 15; // upward from forward (M=20 E=15)
    Roll = 0; // outward from top
    //- Screws *c
    /* [Hidden] */
    ID = 0;
    OD = 1;
    LENGTH = 2;
    /* [Screws and Inserts] */
    ClampInsert = [3.0,4.2,8.0];
    ClampScrew = [3.0,5.9,35.0]; // thread dia, head OD, screw length
    ClampScrewWasher = [3.0,6.75,0.5];
    ClampScrewNut = [3.0,6.1,4.0]; // nyloc nut
    /* [Hidden] */
    F_NAME = 0;
    F_GRIPOD = 1;
    F_GRIPLEN = 2;
    LightBodies = [
    ["AnkerLC90",26.6,48.0],
    ["AnkerLC40",26.6,55.0],
    ["J5TactV2",25.0,30.0],
    ["InnovaX5",22.0,55.0]
    ];
    //- Fairing Bracket
    // Magic numbers taken from the actual fairing mount
    /* [Hidden] */
    inch = 25.4;
    BracketHoleOD = 0.25 * inch; // 1/4-20 bolt holes
    BracketHoleOC = 1.0 * inch; // fairing hole spacing
    // usually 1 inch, but 15/16 on one fairing
    Bracket = [48.0,16.3,3.6 – 0.6]; // fairing bracket end plate overall size
    BracketHoleOffset = (3/8) * inch; // end to hole center
    BracketM = 3.0; // endcap arc height
    BracketR = (pow(BracketM,2) + pow(Bracket[1],2)/4) / (2*BracketM); // … radius
    //- Base plate dimensions
    Plate = [100.0,30.0,6*ThreadThick + Bracket[2]];
    PlateRad = Plate[1]/4;
    RoundEnds = true;
    echo(str("Base plate thick: ",Plate[2]));
    //- Select flashlight data from table
    echo(str("Flashlight: ",FlashName));
    FlashIndex = search([FlashName],LightBodies,1,0)[F_NAME];
    //- Set ball dimensions
    BallWall = 5.0; // max ball wall thickness
    echo(str("Ball wall: ",BallWall));
    BallOD = IntegerMultiple(LightBodies[FlashIndex][F_GRIPOD] + 2*BallWall,1.0);
    echo(str(" OD: ",BallOD));
    BallLength = IntegerMultiple(min(sqrt(pow(BallOD,2) – pow(LightBodies[FlashIndex][F_GRIPOD],2)) – 2*4*ThreadThick,
    LightBodies[FlashIndex][F_GRIPLEN]),1.0);
    echo(str(" length: ",BallLength));
    BallSides = 8*4;
    //- Set clamp ring dimensions
    ClampOD = 50;
    echo(str("Clamp OD: ",ClampOD));
    ClampLength = min(20.0,0.75*BallLength);
    echo(str(" length: ",ClampLength));
    ClampScrewOC = IntegerMultiple((ClampOD + BallOD)/2,1);
    echo(str(" screw OC: ",ClampScrewOC));
    TiltMirror = (Side == "Right") ? [0,0,0] : [0,1,0];
    //- Adjust hole diameter to make the size come out right
    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,$fn=Sides);
    }
    //- Fairing Bracket
    // This part of the fairing mount supports the whole flashlight mount
    // Centered on screw hole
    module Bracket() {
    linear_extrude(height=Bracket[2],convexity=2)
    difference() {
    translate([(Bracket[0]/2 – BracketHoleOffset),0,0])
    offset(delta=ThreadWidth)
    intersection() {
    square([Bracket[0],Bracket[1]],center=true);
    union() {
    for (i=[-1,0,1]) // middle circle fills gap
    translate([i*(Bracket[0]/2 – BracketR),0])
    circle(r=BracketR);
    }
    }
    circle(d=BracketHoleOD/cos(180/8),$fn=8); // dead center at the origin
    }
    }
    //- General plate shape
    // Centered on the hole for the fairing bracket
    module PlateBlank() {
    difference() {
    translate([BracketHoleOC,0,0])
    intersection() {
    translate([0,0,Plate[2]/2]) // select upper half of spheres
    cube(Plate,center=true);
    hull()
    if (RoundEnds)
    for (i=[-1,1])
    translate([i*(Plate[0]/2 – PlateRad),0,0])
    resize([Plate[1]/2,Plate[1],2*Plate[2]])
    sphere(r=PlateRad); // nice round ends!
    else
    for (i=[-1,1], j=[-1,1])
    translate([i*(Plate[0]/2 – PlateRad),j*(Plate[1]/2 – PlateRad),0])
    resize([2*PlateRad,2*PlateRad,2*Plate[2]])
    sphere(r=PlateRad); // nice round corners!
    }
    translate([2*BracketHoleOC,0,-Protrusion]) // punch screw holes
    PolyCyl(BracketHoleOD,2*Plate[2],8);
    translate([0,0,-Protrusion])
    PolyCyl(BracketHoleOD,2*Plate[2],8);
    }
    }
    //- Inner plate
    module InnerPlate() {
    difference() {
    PlateBlank();
    translate([0,0,Plate[2] – Bracket[2] + Protrusion]) // punch fairing bracket
    Bracket();
    }
    }
    //- Slotted ball around flashlight
    // Print with brim to ensure adhesion!
    module SlotBall() {
    NumSlots = 8*2; // must be even, half cut from each end
    SlotWidth = 2*ThreadWidth;
    SlotBaseThick = 10*ThreadThick; // enough to hold finger ends together
    RibLength = (BallOD – LightBodies[FlashIndex][F_GRIPOD])/2;
    translate([0,0,(Layout == "Build") ? BallLength/2 : 0])
    rotate([0,(Layout == "Show") ? 90 : 0,0])
    difference() {
    intersection() {
    sphere(d=BallOD,$fn=2*BallSides); // basic ball
    cube([2*BallOD,2*BallOD,BallLength],center=true); // trim to length
    }
    translate([0,0,-LightBodies[FlashIndex][F_GRIPOD]])
    rotate(180/BallSides)
    PolyCyl(LightBodies[FlashIndex][F_GRIPOD],2*BallOD,BallSides); // remove flashlight body
    for (i=[0:NumSlots/2 – 1]) { // cut slots
    a=i*(2*360/NumSlots);
    SlotCutterLength = LightBodies[FlashIndex][F_GRIPOD];
    rotate(a)
    translate([SlotCutterLength/2,0,SlotBaseThick])
    cube([SlotCutterLength,SlotWidth,BallLength],center=true);
    rotate(a + 360/NumSlots)
    translate([SlotCutterLength/2,0,-SlotBaseThick])
    cube([SlotCutterLength,SlotWidth,BallLength],center=true);
    }
    }
    color("Yellow")
    if (Support && (Layout == "Build")) {
    for (i=[0:NumSlots-1]) {
    a = i*360/NumSlots;
    rotate(a + 180/NumSlots)
    translate([(LightBodies[FlashIndex][F_GRIPOD] + RibLength)/2 + ThreadWidth,0,BallLength/(2*4)])
    cube([RibLength,2*ThreadWidth,BallLength/4],center=true);
    }
    }
    }
    //- Clamp around flashlight ball
    module BallClamp(Section="All") {
    BossLength = ClampScrew[LENGTH] – 1*ClampScrewWasher[LENGTH];
    BossOD = ClampInsert[OD] + 2*(6*ThreadWidth);
    difference() {
    union() {
    intersection() {
    sphere(d=ClampOD,$fn=BallSides); // exterior ball clamp
    cube([ClampLength,2*ClampOD,2*ClampOD],center=true); // aiming allowance
    }
    hull()
    for (j=[-1,1])
    translate([0,j*ClampScrewOC/2,-BossLength/2])
    cylinder(d=BossOD,h=BossLength,$fn=6);
    }
    sphere(d=(BallOD + 1*ThreadThick),$fn=BallSides); // interior ball with minimal clearance
    for (j=[-1,1]) {
    translate([0,j*ClampScrewOC/2,-ClampOD]) // screw clearance
    PolyCyl(ClampScrew[ID],2*ClampOD,6);
    translate([0,j*ClampScrewOC/2, // insert clearance
    -(BossLength/2 – ClampInsert[LENGTH] – 3*ThreadThick)])
    rotate([0,180,0])
    PolyCyl(ClampInsert[OD],2*ClampOD,6);
    translate([0,j*ClampScrewOC/2, // insert transition
    -(BossLength/2 – ClampInsert[LENGTH] – 3*ThreadThick)])
    cylinder(d1=ClampInsert[OD]/cos(180/6),d2=ClampScrew[ID],h=6*ThreadThick,$fn=6);
    }
    if (Section == "Top")
    translate([0,0,-ClampOD/2])
    cube([2*ClampOD,2*ClampOD,ClampOD],center=true);
    else if (Section == "Bottom")
    translate([0,0,ClampOD/2])
    cube([2*ClampOD,2*ClampOD,ClampOD],center=true);
    }
    color("Yellow")
    if (Support) { // ad-hoc supports
    NumRibs = 6;
    RibLength = 0.5 * BallOD;
    RibWidth = 1.9*ThreadWidth;
    SupportOC = ClampLength / NumRibs;
    if (Section == "Top") // base plate for adhesion
    translate([0,0,ThreadThick])
    cube([ClampLength + 6*ThreadWidth,RibLength,2*ThreadThick],center=true);
    else if (Section == "Bottom")
    translate([0,0,-ThreadThick])
    cube([ClampLength + 6*ThreadWidth,RibLength,2*ThreadThick],center=true);
    render(convexity=2*NumRibs)
    intersection() {
    sphere(d=BallOD – 0*ThreadWidth); // cut at inner sphere OD
    cube([ClampLength + 2*ThreadWidth,RibLength,BallOD],center=true);
    if (Section == "Top") // select only desired section
    translate([0,0,ClampOD/2])
    cube([2*ClampOD,2*ClampOD,ClampOD],center=true);
    else if (Section == "Bottom")
    translate([0,0,-ClampOD/2])
    cube([2*ClampOD,2*ClampOD,ClampOD],center=true);
    union() { // ribs for E-Z build
    for (j=[-1,0,1])
    translate([0,j*SupportOC,0])
    cube([ClampLength,RibWidth,1.0*BallOD],center=true);
    for (i=[0:NumRibs]) // allow NumRibs + 1 to fill the far end
    translate([i*SupportOC – ClampLength/2,0,0])
    rotate([0,90,0])
    cylinder(d=BallOD – 2*ThreadThick,
    h=RibWidth,$fn=BallSides,center=true);
    }
    }
    }
    }
    //- Mount between fairing plate and flashlight ball
    // Build with support for bottom of clamp screws!
    module Mount() {
    TextRotate = (Side == "Right") ? 0 : 180;
    MountShift = [ClampOD*sin(ToeIn/2),
    0,
    ClampOD/2];
    difference() {
    translate([-BracketHoleOC,0,0]) // put bracket center at origin
    PlateBlank();
    mirror([0,1,0])
    translate([0,0,-Protrusion])
    linear_extrude(height=3*ThreadThick + Protrusion) {
    translate([BracketHoleOC + 15,0,0])
    text(text=">>>",size=5,spacing=1.20,font="Arial",halign="center",valign="center");
    translate([-BracketHoleOC,8,0]) rotate(TextRotate)
    text(text=str("Toe ",ToeIn),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
    translate([-BracketHoleOC,-8,0]) rotate(TextRotate)
    text(text=str("Tilt ",Tilt),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
    translate([BracketHoleOC,-8,0]) rotate(TextRotate)
    text(text=Side,size=5,spacing=1.20,font="Arial",halign="center",valign="center");
    translate([BracketHoleOC,8,0]) rotate(TextRotate)
    text(text=str("Roll ",Roll),size=5,spacing=1.20,font="Arial",halign="center",valign="center");
    translate([-(BracketHoleOC + 15),0,0])
    rotate(90)
    text(text="KE4ZNU",size=4,spacing=1.20,font="Arial",halign="center",valign="center");
    }
    }
    mirror(TiltMirror) {
    translate(MountShift)
    rotate([-Roll,ToeIn,Tilt])
    BallClamp("Bottom");
    color("Yellow")
    if (MountSupport) { // anchor outer corners at worst overhang
    RibWidth = 1.9*ThreadWidth;
    SupportOC = 0.1 * ClampLength;
    difference() {
    rotate([0,0,Tilt])
    translate([(ClampOD – BallOD)*sin(ToeIn/2),0,0])
    for (i=[-4.5,-2.5,0,2.0,4.5])
    translate([i*SupportOC – 0.0,0,(5 + Plate[2])/2])
    cube([RibWidth,0.7*ClampOD,(5 + Plate[2])],center=true);
    translate(MountShift)
    rotate([-Roll,ToeIn,Tilt])
    sphere(d=ClampOD – 2*ThreadWidth,$fn=BallSides);
    }
    }
    }
    }
    //- Build things
    if (Component == "Bracket")
    Bracket();
    if (Component == "Ball")
    SlotBall();
    if (Component == "BallClamp")
    if (Layout == "Show")
    BallClamp("All");
    else if (Layout == "Build")
    BallClamp("Top");
    if (Component == "Mount")
    Mount();
    if (Component == "Plates") {
    translate([0,0.7*Plate[1],0])
    InnerPlate();
    translate([0,-0.7*Plate[1],0])
    PlateBlank();
    }
    if (Component == "Complete") {
    translate([-BracketHoleOC,0,0])
    PlateBlank();
    mirror(TiltMirror) {
    translate([0,0,ClampOD/2]) {
    rotate([-Roll,ToeIn,Tilt])
    SlotBall();
    rotate([-Roll,ToeIn,Tilt])
    BallClamp();
    }
    }
    }