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

  • Propane Tank QD Fitting Adapter, PETG Edition

    Smoking bacon during the winter months brought the third tank into play, requiring the POL-to-QD adapter I’d had in the drawer for just such an occasion. Not much to my surprise, the old PLA fitting adapter snapped along the layers near the outside end of the triangular snout:

    IMG_20180408_125018
    IMG_20180408_125018

    So I ran off the two orange ones in PETG with six perimeter layers and 50% infill density:

    Propane QD Adapter Tool - Slic3r
    Propane QD Adapter Tool – Slic3r

    Those should last roughly forever …

    The OpenSCAD source code as a GitHub Gist:

    // Propane tank QD connector adapter tool
    // Ed Nisley KE4ZNU November 2012
    // 2018-04-08 toss MCAD includes overboard
    //- Extrusion parameters must match reality!
    // Print with about half a dozen perimeter threads and 50% infill
    ThreadThick = 0.25;
    ThreadWidth = 2.0 * ThreadThick;
    HoleWindage = 0.2;
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    Protrusion = 0.1; // make holes end cleanly
    inch = 25.4;
    //———————-
    // Dimensions
    WrenchSize = (5/8) * inch; // across the flats
    WrenchThick = 10;
    NoseDia = 8.6;
    NoseLength = 9.0;
    LockDia = 12.5;
    LockRingLength = 1.0;
    LockTaperLength = 1.5;
    TriDia = 15.1;
    TriWide = 12.2; // from OD across center to triangle side
    TriOffset = TriWide – TriDia/2; // from center to triangle side
    TriLength = 9.8;
    NeckDia = TriDia;
    NeckLength = 4.0;
    //———————-
    // 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);
    }
    /*
    module ShowPegGrid(Space = 10.0,Size = 1.0) {
    Range = floor(50 / Space);
    for (x=[-Range:Range])
    for (y=[-Range:Range])
    translate([x*Space,y*Space,Size/2])
    %cube(Size,center=true);
    }
    */
    //——————-
    // Build it…
    $fn = 4*6;
    //ShowPegGrid();
    union() {
    translate([0,0,(WrenchThick + NeckLength + TriLength – LockTaperLength – LockRingLength + Protrusion)])
    cylinder(r1=NoseDia/2,r2=LockDia/2,h=LockTaperLength);
    translate([0,0,(WrenchThick + NeckLength + TriLength – LockRingLength)])
    cylinder(r=LockDia/2,h=LockRingLength);
    difference() {
    union() {
    translate([0,0,WrenchThick/2])
    cube([WrenchSize,WrenchSize,WrenchThick],center=true);
    cylinder(r=TriDia/2,h=(WrenchThick + NeckLength +TriLength));
    cylinder(r=NoseDia/2,h=(WrenchThick + NeckLength + TriLength + NoseLength));
    }
    for (a=[-1:1]) {
    rotate(a*120)
    translate([(TriOffset + WrenchSize/2),0,(WrenchThick + NeckLength + TriLength/2 + Protrusion/2)])
    cube([WrenchSize,WrenchSize,(TriLength + Protrusion)],center=true);
    }
    }
    }