OpenSCAD source code: Tour Easy seat clamp mount for rear running light

Rear Running Light Seat Clamp.scad

// Rear running light clamp for Tour Easy seat strut
// Ed Nisley - KE4ZNU - 2021-09

Layout = "Show";             // [Show,Build,Block]

Section = true;

/* [Hidden] */

ThreadThick = 0.25;
ThreadWidth = 0.40;

HoleWindage = 0.2;

Protrusion = 0.1;     // make holes end cleanly

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

ID = 0;
OD = 1;
LENGTH = 2;

inch = 25.4;

//----------------------
// Dimensions
// Light case along X axis, seat strut along Y, Z=0 at strut centerline

LightOD = 25.4 + HoleWindage;

StrutOD = 5/8 * inch + HoleWindage;

PlateThick = 1/16 * inch;

WallThick = 2.0;

Kerf = ThreadThick;

Screw = [3.0,6.8,4.0];                  // M3 OD=washer, length=nut + washers
Insert = [3.0,5.4,8.0 + 1.0];           // splined brass insert

RoundRadius = IntegerMultiple(Screw[OD]/2,0.5);             // corner rounding

ScrewOC = [IntegerMultiple(StrutOD + 2*WallThick + Screw[ID],1.0),
           IntegerMultiple(LightOD + 2*WallThick + Screw[ID],1.0)];

echo(str("Screw OC: ",ScrewOC));

BlockSize = [ScrewOC.x + Insert[OD] + 2*WallThick,
             ScrewOC.y + Insert[OD] + 2*WallThick,
             LightOD + StrutOD + 3*WallThick];

echo(str("Block: ",BlockSize));

BaseOffset = -(WallThick + LightOD/2);                  // block bottom to centerline
StrutOffset = LightOD/2 + WallThick + StrutOD/2;        // light centerline to strut centerline

echo(str("Strut screw min: ",IntegerMultiple(PlateThick + WallThick + StrutOD/2 + Insert[LENGTH]/2,1.0)));
echo(str("Light screw min: ",IntegerMultiple(PlateThick + WallThick + LightOD/2 + Insert[LENGTH]/2,1.0)));

NumSides = 2*3*4;

//----------------------
// 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);
}

// Block with light along X axis

module Block() {

  difference() {
    hull()
      for (i=[-1,1], j=[-1,1])
        translate([i*(BlockSize.x/2 - RoundRadius),j*(BlockSize.y/2 - RoundRadius),BaseOffset])
          cylinder(r=RoundRadius,h=BlockSize.z,$fn=NumSides);

    for (i=[-1,1], j=[-1,1])
      translate([i*ScrewOC.x/2,j*ScrewOC.y/2,BaseOffset - Protrusion])
        rotate(180/8)
          PolyCyl(Screw[ID],BlockSize.z + 2*Protrusion,8);

    for (i=[-1,1], j=[-1,1])
      translate([i*ScrewOC.x/2,j*ScrewOC.y/2,0]) {
        translate([0,0,-Protrusion])
          rotate(180/8)
            PolyCyl(Insert[OD],Insert[LENGTH] + 1*Protrusion,8);
        translate([0,0,(StrutOffset - Insert[LENGTH] - Kerf/2 + Protrusion)])
          rotate(180/8)
            PolyCyl(Insert[OD],Insert[LENGTH] + 1*Protrusion,8);
      }

    translate([-BlockSize.x,0,0])
      rotate([0,90,0])
        cylinder(d=LightOD,h=2*BlockSize.x,$fn=NumSides);

   translate([0,BlockSize.y,StrutOffset])
      rotate([90,0,0])
        cylinder(d=StrutOD,h=2*BlockSize.y,$fn=NumSides);

    translate([0,0,StrutOffset])
      cube([2*BlockSize.x,2*BlockSize.y,Kerf],center=true);

    cube([2*BlockSize.x,2*BlockSize.y,Kerf],center=true);

  }

}


//- Build it

if (Layout == "Block")
  if (Section)
    difference() {
      Block();
      rotate(atan(ScrewOC.y/ScrewOC.x))
        translate([0,BlockSize.y,0])
          cube(2*BlockSize,center=true);
    }
  else
    Block();

if (Layout == "Show") {
  Block();

  color("Green",0.25)
    translate([-BlockSize.x,0,0])
      rotate([0,90,0])
        cylinder(d=LightOD,h=2*BlockSize.x,$fn=NumSides);

  color("Green",0.25)
    translate([0,BlockSize.y,StrutOffset])
      rotate([90,0,0])
        cylinder(d=StrutOD,h=2*BlockSize.y,$fn=NumSides);
}

if (Layout == "Build") {
  translate([-1.2*BlockSize.x,0,-BaseOffset])
    difference() {
      Block();
      translate([0,0,BlockSize.z])
        cube(2*BlockSize,center=true);
    }

  translate([1.2*BlockSize.x,0,StrutOD/2 + WallThick])
    difference() {
      rotate([180,0,0])
      translate([0,0,-StrutOffset])
        Block();
      translate([0,0,BlockSize.z])
        cube(2*BlockSize,center=true);
    }

  translate([0,0,StrutOffset - Kerf/2])
    rotate([180,0,0])
      intersection() {
          Block();
        translate([0,0,StrutOffset/2])
          cube([2*BlockSize.x,2*BlockSize.y,StrutOffset],center=true);
      }
  }

More details on my blog at https://wp.me/poZKh-ap7