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The New Hotness

  • Round Soaker Hose Splint

    One of two new round rubber soaker hoses arrived with a slight crimp, enough to suggest it would crumble at an inopportune moment. Rather than return the hose for something that’s not an obvious failure, I clamped the crimp:

    Round Soaker Hose Splice - top
    Round Soaker Hose Splice – top

    Unlike the clamps for the punctured flat soaker hoses, this one doesn’t need to withstand much pressure and hold back a major leak, so I made the pieces a bit thicker and dispensed with the aluminum backing plates:

    Round Soaker Hose Splice - bottom
    Round Soaker Hose Splice – bottom

    The solid model is basically the same as for the flat hoses, with a slightly oval cylinder replacing the three channels:

    Round Soaker Hose Splice - OpenSCAD model
    Round Soaker Hose Splice – OpenSCAD model

    The OpenSCAD source code as a GitHub Gist:

    // Rubber Soaker Hose Splice
    // Ed Nisley KE4ZNU 2020-03
    Layout = "Build"; // [Hose,Block,Show,Build]
    TestFit = false; // true to build test fit slice from center
    //- Extrusion parameters must match reality!
    /* [Hidden] */
    ThreadThick = 0.25;
    ThreadWidth = 0.40;
    HoleWindage = 0.2;
    Protrusion = 0.1; // make holes end cleanly
    inch = 25.4;
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    ID = 0;
    OD = 1;
    LENGTH = 2;
    //———-
    // Dimensions
    // Hose lies along X axis
    Hose = [200,14.5,13.6]; // X = longer than anything else
    // 8-32 stainless screws
    Screw = [4.1,8.0,3.0]; // OD = head LENGTH = head thickness
    Washer = [4.4,9.5,1.0];
    Nut = [4.1,9.7,6.0];
    Block = [50.0,Hose.y + 2*Washer[OD],4.0 + 1.5*Hose.z]; // overall splice block size
    echo(str("Block: ",Block));
    Kerf = 1.0; // cut through middle to apply compression
    CornerRadius = Washer[OD]/2;
    NumScrews = 3; // screws along each side of cable
    ScrewOC = [(Block.x – 2*CornerRadius) / (NumScrews – 1),
    Block.y – 2*CornerRadius,
    2*Block.z // ensure complete holes
    ];
    echo(str("Screw OC: x=",ScrewOC.x," y=",ScrewOC.y));
    //———————-
    // 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(d=(FixDia + HoleWindage),h=Height,$fn=Sides);
    }
    // Hose shape
    // This includes magic numbers measured from reality
    module HoseProfile() {
    NumSides = 12*4;
    rotate([0,-90,0])
    translate([0,0,-Hose.x/2])
    resize([Hose.z,Hose.y,0])
    cylinder(d=Hose.z,h=Hose.x,$fn=NumSides);
    }
    // Outside shape of splice Block
    // Z centered on hose rim circles, not overall thickness through center ridge
    module SpliceBlock() {
    difference() {
    hull()
    for (i=[-1,1], j=[-1,1]) // rounded block
    translate([i*(Block.x/2 – CornerRadius),j*(Block.y/2 – CornerRadius),-Block.z/2])
    cylinder(r=CornerRadius,h=Block.z,$fn=4*8);
    for (i = [0:NumScrews – 1], j=[-1,1]) // screw holes
    translate([-(Block.x/2 – CornerRadius) + i*ScrewOC.x,
    j*ScrewOC.y/2,
    -(Block.z/2 + Protrusion)])
    PolyCyl(Screw[ID],Block.z + 2*Protrusion,6);
    cube([2*Block.x,2*Block.y,Kerf],center=true); // slice through center
    }
    }
    // Splice block less hose
    module ShapedBlock() {
    difference() {
    SpliceBlock();
    HoseProfile();
    }
    }
    //———-
    // Build them
    if (Layout == "Hose")
    HoseProfile();
    if (Layout == "Block")
    SpliceBlock();
    if (Layout == "Show") {
    difference() {
    SpliceBlock();
    HoseProfile();
    }
    color("Green",0.25)
    HoseProfile();
    }
    if (Layout == "Build") {
    SliceOffset = TestFit && !NumScrews%2 ? ScrewOC.x/2 : 0;
    intersection() {
    translate([SliceOffset,0,Block.z/4])
    if (TestFit)
    cube([ScrewOC.x/2,4*Block.y,Block.z/2],center=true);
    else
    cube([4*Block.x,4*Block.y,Block.z/2],center=true);
    union() {
    translate([0,0.6*Block.y,Block.z/2])
    ShapedBlock();
    translate([0,-0.6*Block.y,Block.z/2])
    rotate([0,180,0])
    ShapedBlock();
    }
    }
    }