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The New Hotness

  • HQ Sixteen: Improved Fabric Rod Bushings

    Descending from the previous bearings / sleeves / bushings, I added a rib to hold them in place as the rod slides back and forth while fiddling with fabric:

    HQ Sixteen - Rod Bushing - rib retainer - solid model - build view
    HQ Sixteen – Rod Bushing – rib retainer – solid model – build view

    An idealized serving suggestion:

    HQ Sixteen - Rod Bushing - rib retainer - solid model - show view
    HQ Sixteen – Rod Bushing – rib retainer – solid model – show view

    Which might count as the “better design” I expected it would need.

    They’re still almost invisible in use:

    HQ Sixteen - Rod Bushing - rib retainer
    HQ Sixteen – Rod Bushing – rib retainer

    Which is as it should be: inconspicuous, no more black dust, and E-Z rotation.

    The modified OpenSCAD source code is added to the original GitHub Gist:

    // Bushing for HQ Sixteen table rods
    // Ed Nisley – KE4ZNU
    // 2026-02-20
    // 2026-09-29 add retaining rib
    include <BOSL2/std.scad>
    Layout = "Show"; // [Show,Build]
    /* [Hidden] */
    ID = 0;
    OD = 1;
    LENGTH = 2;
    HoleWindage = 0.2;
    Protrusion = 0.1;
    NumSides = 8*3*2*4;
    $fn=NumSides;
    Rod = [25.0,28.7,100.0]; // very short rod
    Sleeve = [Rod[OD] + 0.3,31.2 – 0.2,9.0]; // LENGTH = overall
    Rim = [Sleeve[ID],Sleeve[OD] + 6.0,0.6];
    LockRing = [Sleeve[ID],Sleeve[OD] + 2*(1.0),4.0]; // locks sleeve on plate
    IdlerLength = 15.0; // far right end of rods
    NumSlots = 2*4;
    Kerf = 1.0;
    Gap = 5.0;
    module Bushing(oal,lk=false) {
    difference() {
    union() {
    tube(oal,id=Sleeve[ID],od=Sleeve[OD],anchor=BOTTOM);
    tube(Rim[LENGTH],id=Rim[ID],od=Rim[OD],anchor=BOTTOM);
    if (lk)
    up(oal)
    tube(LockRing[LENGTH],id=LockRing[ID],od=LockRing[OD],chamfer=LockRing[LENGTH]/3,anchor=TOP);
    }
    for (a=[0:NumSlots-1])
    zrot(a*360/NumSlots)
    up(oal/4 + Rim[LENGTH])
    right(Sleeve[ID]/2)
    cuboid([Sleeve[OD],Kerf,oal],anchor=BOTTOM);
    }
    }
    //—–
    // Build things
    if (Layout == "Show") {
    color("Gray",0.5)
    xcyl(Rod[LENGTH],d=Rod[OD]);
    right(Rod[LENGTH]/3)
    zrot(180) yrot(90)
    Bushing(Sleeve[LENGTH]);
    left(Rod[LENGTH]/3)
    yrot(90)
    Bushing(IdlerLength,lk=true);
    }
    if (Layout == "Build") {
    right(Rim[OD]/2 + Gap/2)
    Bushing(Sleeve[LENGTH]);
    left(Rim[OD]/2 + Gap/2)
    Bushing(IdlerLength,lk=true);
    }
    view raw HQ Sixteen – Rod Bushing.scad hosted with ❤ by GitHub
    // Bearing sleeve for HQ Sixteen table rods
    // Ed Nisley – KE4ZNU
    // 2026-02-20
    include <BOSL2/std.scad>
    Layout = "Show"; // [Show,Build]
    /* [Hidden] */
    ID = 0;
    OD = 1;
    LENGTH = 2;
    HoleWindage = 0.2;
    Protrusion = 0.1;
    NumSides = 8*3*2*4;
    $fn=NumSides;
    Rod = [25.0,28.7,100.0]; // very short rod
    Sleeve = [Rod[OD] + 0.3,31.2 – 0.2,9.0]; // LENGTH = overall
    Rim = [Sleeve[ID],Sleeve[OD] + 6.0,0.6];
    IdlerLength = 15.0;
    NumSlots = 2*4;
    Kerf = 1.0;
    Gap = 5.0;
    module Bearing(oal) {
    difference() {
    union() {
    tube(oal,id=Sleeve[ID],od=Sleeve[OD],anchor=BOTTOM);
    tube(Rim[LENGTH],id=Rim[ID],od=Rim[OD],anchor=BOTTOM);
    }
    for (a=[0:NumSlots-1])
    zrot(a*360/NumSlots)
    up(oal/4 + Rim[LENGTH])
    right(Sleeve[ID]/2)
    cuboid([Sleeve[OD],Kerf,oal],anchor=BOTTOM);
    }
    }
    //—–
    // Build things
    if (Layout == "Show") {
    color("Gray",0.5)
    xcyl(Rod[LENGTH],d=Rod[OD]);
    right(Rod[LENGTH]/3)
    yrot(90)
    Bearing(Sleeve[LENGTH]);
    left(Rod[LENGTH]/3)
    yrot(90)
    Bearing(IdlerLength);
    }
    if (Layout == "Build") {
    right(Rim[OD]/2 + Gap/2)
    Bearing(Sleeve[LENGTH]);
    left(Rim[OD]/2 + Gap/2)
    Bearing(IdlerLength);
    }
    view raw Rod Bearing Sleeve.scad hosted with ❤ by GitHub