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.

Category: Software

General-purpose computers doing something specific

  • HQ Sixteen: Padded Table Shims

    HQ Sixteen: Padded Table Shims

    The HQ Sixteen has been running at higher speeds as Mary practices using its stitch regulator and the vibrations shook several of the table shims (blocks, whatever) onto the floor. I hope a layer of EVA foam provides enough compliance to keep them in place:

    HQ Sixteen - padded table shim - installed
    HQ Sixteen – padded table shim – installed

    The foam is 2 mm thick, so subtracting that from the nominal thickness makes the new blocks come out right.

    A short module extracts the footprint for export as an SVG image to laser-cut both the foam and the adhesive sheet required to stick it in place:

    module ShimPad(Thickness = PadThick) {
    
        if (Thickness)
            linear_extrude(height=Thickness)
                projection(cut=true)
                    ShimBlock();
        else
            projection(cut=true)
                ShimBlock();
    
    }
    

    It turns out linear_extrude() chokes on a zero height.

    When handed a nonzero Thickness, the code generates a simulated foam sheet:

    HQ Sixteen - table shims - solid model - padded
    HQ Sixteen – table shims – solid model – padded

    The footprint looks about like you’d expect:

    HQ Sixteen - table shims - solid model - pad outline
    HQ Sixteen – padded table shim – installed

    Import into LightBurn, duplicate it sufficiently, set the speed & power & kerf for EVA foam, then cut ’em out:

    HQ Sixteen - table shims - padding cuts
    HQ Sixteen – table shims – padding cuts

    Ditto for the adhesive, stick together, and upgrade the fleet.

    If these shake loose, snippets of adhesive film will stick them firmly to the underside of the table panels.

    Update: Yeah, they needed sticky snippets. Whole lotta shakin’ goin’ on with that machine!

  • Floor Lamp Remote Control Holder

    Floor Lamp Remote Control Holder

    The remote control for the floor lamp across the Reading Room will never again wander away into the clutter:

    Floor lamp remote holder - in use
    Floor lamp remote holder – in use

    The magnet in its back snuggles against a steel disk embedded in the holder:

    Floor lamp remote holder - installed
    Floor lamp remote holder – installed

    A magnetic field visualization sheet revealed the magnet:

    Floor lamp remote holder - magnet field visualization
    Floor lamp remote holder – magnet field visualization

    Extract the remote’s profiles with a contour gauge:

    Floor lamp remote holder - pin contour gauge
    Floor lamp remote holder – pin contour gauge

    Trace the outlines and lay smooth curves around them with Inkscape:

    Remote profiles - Inkscape curves
    Remote profiles – Inkscape curves

    They needed a slight lengthening to account for the gauge pin diameter & deflection, but this isn’t a precision project.

    Do the same with a scan of the front face, import the curves into OpenSCAD, extrude them, create a solid model of the remote from their mutual intersection, then add a cylinder to punch the depression for the steel plate:

    Floor Lamp Remote Holder - solid model - bottom
    Floor Lamp Remote Holder – solid model – bottom

    The chonky model corners stick out too far compared to the stylin’ curves on the real remote, but I made the holder shorter than the remote specifically to avoid fussing with such details.

    Subtract the remote from a nicely rounded cuboid and knock out a cylinder for the pipe it’ll mount on to produce the holder:

    Floor Lamp Remote Holder - solid model - Show view
    Floor Lamp Remote Holder – solid model – Show view

    I briefly considered a circumferential clamp around the pipe before coming to my senses and making the pipe diameter 2 mm larger to accommodate a strip of double-sided foam tape.

    The magnet gets a ferocious grip on the plate and I defined the result to be All Good™.

    The OpenSCAD source code and SVG paths as a GitHub Gist:

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    // Floor Lamp Remote Holder
    // Ed Nisley – KE4ZNU
    // 2025-03-29
    include <BOSL2/std.scad>
    Layout = "Holder"; // [Show,Build,Remote,Holder]
    BaseAngle = 30; // [0:50]
    /* [Hidden] */
    RemoteOA = [92.0,40.0,14.5];
    PoleOD = 16.0; // lamp pole
    MagnetOD = 20.0; // steel plate under magnet
    MagnetOffset = [11.0,0,-2.0];
    TapeThick = 1.2;
    HolderOA = [60.0,35.0,PoleOD/3 + 4.0 + RemoteOA.z/2];
    HolderRadius = 5.0;
    Gap = 10.0;
    //———-
    // Define shapes
    module RemoteBody() {
    union() {
    intersection() {
    fwd(RemoteOA.y/2) up(RemoteOA.z/2)
    linear_extrude(h=RemoteOA.z,center=true)
    import("Floor Lamp Remote – outlines.svg",layer="Top Outline");
    zrot(90) xrot(90)
    linear_extrude(h=RemoteOA.x,center=true)
    import("Floor Lamp Remote – outlines.svg",layer="End Outline");
    xrot(90)
    linear_extrude(h=RemoteOA.y,center=true)
    import("Floor Lamp Remote – outlines.svg",layer="Side Outline");
    }
    translate(MagnetOffset)
    cylinder(d=MagnetOD,h=RemoteOA.z,$fn=4*3*4);
    }
    }
    module Holder() {
    difference() {
    cuboid(HolderOA,anchor=BOTTOM,rounding=HolderRadius,except=TOP);
    down((PoleOD + 2*TapeThick)*(1/2 – 1/3))
    yrot(90)
    cylinder(d=PoleOD + 2*TapeThick,h=2*HolderOA.x,center=true);
    up(HolderOA.z – RemoteOA.z/2)
    RemoteBody();
    }
    }
    //———-
    // Build things
    if (Layout == "Remote")
    RemoteBody();
    if (Layout == "Holder")
    Holder();
    if (Layout == "Show") {
    color("White")
    Holder();
    color("Gray",0.75)
    up(HolderOA.z – RemoteOA.z/2 + Gap)
    RemoteBody();
    color("Green",0.5)
    down((PoleOD + 2*TapeThick)*(1/2 – 1/3))
    yrot(90)
    cylinder(d=PoleOD + 2*TapeThick,h=2*HolderOA.x,center=true);
    }
    if (Layout == "Build") {
    Holder();
    }

  • LED Strip Lights: Window Moulding Mounts

    LED Strip Lights: Window Moulding Mounts

    The object of the game being to tilt the LED strip lights at (maybe) 30° to put more light higher on the wall and further out on the ceiling, with the overriding constraint of no visible holes. Given their eventual home atop the window moulding along the front wall of the Living Sewing Room, these seemed adequate:

    LED Bar Lamp Mount - solid model
    LED Bar Lamp Mount – solid model

    The hole on the angled part fits an M4 brass insert and the recessed holes capture the washer-like head of a sharp-point lath screw.

    Two pairs applied to the lights sitting atop the Fabric Cabinets served to verify the fit:

    LED strip light - moulding mount - on cabinet
    LED strip light – moulding mount – on cabinet

    They’re held firmly by the aluminum extrusion and don’t need a bigger footprint to remain stable.

    So I made another six, stuck on ⅞ inch strips of aluminized Mylar (cut from a bag in much better condition), and drilled holes where they can’t be seen:

    LED strip light - moulding mount - installed
    LED strip light – moulding mount – installed

    It’s almost too bright in there with 3 × 40 W of LED lights washing the wall and ceiling:

    LED strip light - moulding mount - lit
    LED strip light – moulding mount – lit

    I don’t like the cold 6000 K color temperature, but Mary doesn’t mind it. They fill the Sewing Table with shadowless / glareless light, although that kind of light makes the place look like a store.

    I think moving the strip lower and away from the wall could hide the entire mount from view.

    Contrary to what I expected, the Mylar reflectors must be at least an inch tall to avoid Baily’s Beads seen from across the room:

    LED strip light - short reflector
    LED strip light – short reflector

    With all that in mind, we’ll run these for a while to shake out any other improvements.

    The OpenSCAD source code as a GitHub Gist:

    // LED light bar mounts
    // Ed Nisley – KE4ZNU
    // 2025-03-16
    include <BOSL2/std.scad>
    Layout = "Show"; // [Show,Build,ScrewMount,BarMount]
    BaseAngle = 30; // [0:50]
    /* [Hidden] */
    ID = 0;
    OD = 1;
    LENGTH = 2;
    Protusion = 0.1;
    NumSides = 3*4;
    Radius = 1.5;
    $fn = NumSides;
    MouldWidth = 18.0; // nominal (3/4) * INCH, but lots of paint slop
    MouldScrew = [4.7,12.0,2.6]; // clearance, head OD, head thick
    Insert = [4.0,5.5,6.0 + 3.0]; // heat-set brass without pilot end
    BarClip = [33.0,15.0,11.0]; // snaps around led base
    ScrewBlockOA = [MouldWidth,MouldScrew[OD] + 2*Radius + 2.0,10.0];
    BarBlockOA = [BarClip.x*cos(BaseAngle),15.0,BarClip.x*sin(BaseAngle) + 2*ScrewBlockOA.z];
    Gap = 2.0 + max(ScrewBlockOA.y,BarBlockOA.y);
    //———-
    // Define shapes
    module ScrewMount() {
    difference(){
    cuboid(ScrewBlockOA,anchor=BOTTOM,rounding=Radius,except=[FRONT,BOTTOM,LEFT]);
    up(ScrewBlockOA.z – MouldScrew[LENGTH])
    zrot(180/NumSides)
    cylinder(d=MouldScrew[OD],h=MouldScrew[LENGTH] + Protusion);
    down(Protusion)
    cylinder(d=MouldScrew[ID],h=2*ScrewBlockOA.z);
    }
    }
    module BarMount() {
    difference() {
    cuboid(BarBlockOA,anchor=CENTER,rounding=Radius,edges=RIGHT);
    yrot(BaseAngle)
    cube([3*BarBlockOA.x,2*BarBlockOA.y,BarBlockOA.z],anchor=BOTTOM);
    yrot(BaseAngle)
    cylinder(d=Insert[OD],h=2*Insert[LENGTH],anchor=CENTER);
    }
    }
    module Mount() {
    union() {
    right(ScrewBlockOA.x/2) back(ScrewBlockOA.y/2)
    ScrewMount();
    right(BarBlockOA.x/2) fwd(BarBlockOA.y/2) up(BarBlockOA.z/2)
    BarMount();
    }
    }
    //———-
    // Build things
    if (Layout == "ScrewMount")
    ScrewMount();
    if (Layout == "BarMount")
    BarMount();
    if (Layout == "Show")
    Mount();
    if (Layout == "Build") {
    yflip_copy(Gap) Mount();
    }

  • Human Lumbar Vertebrae

    Human Lumbar Vertebrae

    Having once again reawakened a back injury from long ago, I figured these were good for some comic relief:

    L4 L5 vertebrae - assembled
    L4 L5 vertebrae – assembled

    The full-scale L4-L5 vertebrae are from Printables and the ¾ scale L5 is from somewhere I cannot recall. A mother lode of anatomical models is on Thingiverse if you want some 3D printing challenges.

    The L4-L5 pair are part of an extensive human anatomic model locating all the pieces at their proper coordinates, so these two hovered about 800 mm above the XY plane. I ran them through the Grid:Tool mesh editor to center them at the XY origin, then put the bottom-most point at Z=0.

    Rotating them individually in PrusaSlicer and painting only the most essential support got them to this state:

    L4 L5 vertebrae - PrusaSlicer
    L4 L5 vertebrae – PrusaSlicer

    Each one take about three hours, so I ran them individually to reduce surface blemishes and maximize the likelihood of happy outcomes. Worked like a champ.

    The retina-burn orange disk is not anatomically correct, because the InterWebz apparently does not have a model for spinal cartilage:

    L4 L5 vertebrae - assembled - disk detail
    L4 L5 vertebrae – assembled – disk detail

    Instead, it’s a rounded cylinder resized into an oval, with its top and bottom surfaces formed by subtracting the vertebrae:

    L4 L5 vertebrae disk - solid model
    L4 L5 vertebrae disk – solid model

    The OpenSCAD code doing the heavy lifting:

    // Disk between L4 and L5 vertebrae
    // Ed Nisley - KE4ZNU
    // 2025-03-07
    
    Layout = "Show";    // [Show,Build]
    
    include <BOSL2/std.scad>
    
    module Disk() {
      color("Red")
        difference() {
          translate([9,-18,36])
            rotate(110)
            resize([33,45])
            cyl(d=50,h=14,$fn=48,rounding=7,anchor=BOTTOM);
          import("../Spine/human-spinal-column-including-cervical-thoracic-and-lumbar-vertebra-model_files/L4 L5 vertebrae stacked.stl",
            convexity=10);
        }
    }
    
    if (Layout == "Show") {
      Disk();
    
      color("White",0.3)
          import("../Spine/human-spinal-column-including-cervical-thoracic-and-lumbar-vertebra-model_files/L4 L5 vertebrae stacked.stl",
            convexity=10);
    
    }
    
    if (Layout == "Build") {
      Disk();
    
    }
    

    All of the magic numbers come from eyeballometric measurement & successive approximation.

    The Build layout left the disk floating in space, whereupon I used PrusaSlicer to reorient it edge-downward on the platform with painted-on support for minimal distortion:

    L4 L5 vertebrae disk - PrusaSlicer
    L4 L5 vertebrae disk – PrusaSlicer

    Two dots of E6000+ adhesive hold everything together.

    All in all, it was a useful distraction. I’ve been vertically polarized for the last five days and it’s good to be … back.

  • Subpixel Zoo: Capturing the Specimens

    Subpixel Zoo: Capturing the Specimens

    A Hacker News discussion led to the Subpixel Zoo, which led to thinking the patterns might make interesting layered “art”. After fetching the *.webp images and figuring out how to persuade Thunar to display them, the next step was converting them into paths suitable for laser cutting.

    Although the images are algorithmically generated in a common layout, figuring out how to get the outlines as paths seemed to require a journey into the depths of the Pygame library and that would turn into a major digression.

    Instead, start with one of the webp images:

    sq_RGBY
    sq_RGBY

    The deliberate blurring apparently simulates what you see in real life.

    Import the image into LightBurn, which converts it to grayscale under the plausible assumption you’re going to engrave the image on something. Then:

    • Create a rounded rectangle overlaying the lower-left-most subpixel to good eyeballometric accuracy
    • Turn it into a four-element rectangular array, twiddling the center-to-center spacing to match the subpixel layout
    • Duplicate those four upward in another array to create a subpixel block, as marked in the upper-left corner of the original image
    • Slam another array across the bottom row and upward, twiddling the spacing to match the subpixel block spacing along both axes

    Which eventually looks like this:

    SubPixels - LightBurn vector overlay
    SubPixels – LightBurn vector overlay

    I made the final array absurdly large, cropped it with a square to match the template I used for the layered paper patterns, resized the result to be 170 mm on a side, then dropped the square into the middle of the template:

    Subpixel Zoo - Quattron RGBY - LightBurn black mask layer
    Subpixel Zoo – Quattron RGBY – LightBurn black mask layer

    One gotcha: crop the subpixels on a Fill layer so LightBurn will close the truncated edges, then put them on a Line layer for cutting. The doc explains why, although it’s not obvious at first, as is the fact that you must delete the group of shapes outside the square before it looks like anything happened during the cut operation.

    The resulting layout contains all the subpixel rectangles, so it’s what you want for the top black mask layer. Duplicate the pattern and delete the subpixels corresponding to each color, until you have one template for each of the Red / Green / Blue layers:

    Subpixel Zoo - Quattron RGBY - LightBurn layers
    Subpixel Zoo – Quattron RGBY – LightBurn layers

    The blank over on the right is the Yellow layer, which does get a quartet of layer ID holes cut in the lower right corner.

    Then it’s just a matter of cutting the blanks, locating the fixture on the platform, dropping the appropriate color sheet in place, cutting it, then assembling the stack in the gluing fixture:

    Subpixel Zoo - Quattron RGBY
    Subpixel Zoo – Quattron RGBY

    It’s kinda cute, in a techie way.

    I did a bunch of layouts, just to see what they looked like:

    Subpixel Zoo - 8x8 layouts
    Subpixel Zoo – 8×8 layouts

    In person, the RGBY patterns look bright and the RGB patterns seem dull by comparison. I’m using cardstock paper, rather than fancy art paper, which surely makes all the difference.

  • HQ Sixteen: Table Leveling Blocks

    HQ Sixteen: Table Leveling Blocks

    The Handi-Quilter HQ Sixteen rides on two tracks along the 11 foot length of the table, with an unsupported 8 foot span between the legs on each end:

    HQ Sixteen - remounted handlebars in use
    HQ Sixteen – remounted handlebars in use

    Contemporary versions of the table have support struts in the middle that our OG version lacks and, as a result, our table had a distinct sag in the middle. During the course of aligning the table top into a plane surface with tapered wood shims, I discovered the floor was half an inch out of level between the table legs.

    Now that the whole thing has settled into place, I measured the shim thicknesses and made tidy blocks to replace them:

    HQ Sixteen - table shims - finished
    HQ Sixteen – table shims – finished

    The OpenSCAD code has an array with the thickness and the number of blocks:

    SHIM_THICK = 0;
    SHIM_COUNT = 1;
    
    Shims = [
        [3.5,1],
        [5.0,3],
        [6.0,2],
        [6.5,1],
        [7.0,1]
    ];
    

    Yes, I call them “blocks” here and wrote “shims” in the code. A foolish consistency, etc.

    The model is a chamfered block with a chunk removed to leave a tongue of the appropriate thickness:

    HQ Sixteen - table shims - solid model - single
    HQ Sixteen – table shims – solid model

    Building them with the label against the platform produces a nice nubbly surface:

    HQ Sixteen - table shims - solid model
    HQ Sixteen – table shims – PrusaSlicer – bottom

    The labels print first and look lonely out there by themselves:

    HQ Sixteen - table shims - legends
    HQ Sixteen – table shims – legends

    The rest of the first layer fills in around the labels:

    HQ Sixteen - table shims - first layer
    HQ Sixteen – table shims – first layer

    Putting the labels on the bottom makes the wipe tower only two layers tall and eliminates filament changes above those layers. Those eight blocks still took a little over three hours, because there’s a lot of perimeter wrapped around not much interior.

    Having had the foresight to draw a sketch showing where each block would go, I slid one next to its wood shim, yanked the shim out, and declared victory:

    HQ Sixteen - table shims - installed
    HQ Sixteen – table shims – installed

    The tension rod welded under the table rail prevents even more sag, but the struts under the new version of the table show other folks were unhappy with the sag of this one. Another leg or two seems appropriate.

    With the table leveled and the surface aligned, the HQ Sixteen glides easily in all directions. The result isn’t perfect and Mary keeps the anchor block at hand, but the machine now displays much less enthusiasm for rolling toward the middle of the table.

    The OpenSCAD source code as a GitHub Gist:

    // HQ Sixteen – table shims
    // Ed Nisley – KE4ZNU
    // 2025-02-27
    include <BOSL2/std.scad>
    Layout = "Show"; // [Show,Build]
    /* [Hidden] */
    SHIM_THICK = 0;
    SHIM_COUNT = 1;
    Shims = [
    [3.5,1],
    [5.0,3],
    [6.0,2],
    [6.5,1],
    [7.0,1]
    ];
    Block = [40.0,20.0,15.0]; // overall shim size
    Grip = 10.0; // … handle length
    BlockRadius = 1.0; // corner rounding / chamfer
    LabelThick = 0.4;
    LabelSize = 5.5;
    LabelFont = "Arial:style:Bold";
    LabelColor = "Red";
    Protrusion = 0.1;
    Gap = 5.0;
    //———-
    // Define shim shape
    module ShimBlock(Height = Shims[0][SHIM_THICK],Part="All") {
    if (Part == "Block" || Part == "All")
    difference() {
    left(Grip)
    cuboid(Block,anchor=BOTTOM + LEFT,chamfer=BlockRadius);
    up(Height)
    cube(Block + 2*[Protrusion,Protrusion,0],anchor=BOTTOM + LEFT);
    left(Grip/2 – BlockRadius/2) fwd(Block.y/2 – LabelThick) up(Block.z/2)
    xrot(90) zrot(-90)
    linear_extrude(height=LabelThick + Protrusion,convexity=20)
    text(text=format_fixed(Height,1),size=LabelSize,spacing=1.00,
    font=LabelFont,halign="center",valign="center");
    }
    if (Part == "Text" || Part == "All")
    color(LabelColor)
    left(Grip/2 – BlockRadius/2) fwd(Block.y/2 – LabelThick) up(Block.z/2)
    xrot(90) zrot(-90)
    linear_extrude(height=LabelThick,convexity=20)
    text(text=format_fixed(Height,1),size=LabelSize,spacing=1.00,
    font=LabelFont,halign="center",valign="center");
    }
    //———-
    // Build them all
    if (Layout == "Show")
    ShimBlock();
    if (Layout == "Build") {
    for (j=[0:len(Shims)-1])
    back(j*(Block.z + Gap))
    for (i=[0:(Shims[j][SHIM_COUNT] – 1)])
    right(i*(Block.x + Gap))
    up(Block.y/2) xrot(90)
    ShimBlock(Shims[j][SHIM_THICK],Part="Block");
    for (j=[0:len(Shims)-1])
    back(j*(Block.z + Gap))
    for (i=[0:(Shims[j][SHIM_COUNT] – 1)])
    right(i*(Block.x + Gap))
    up(Block.y/2) xrot(90)
    ShimBlock(Shims[j][SHIM_THICK],Part="Text");
    }
  • HQ Sixteen: Stylus Laser Ball Mount

    HQ Sixteen: Stylus Laser Ball Mount

    My version of a mount for the HQ Sixteen’s “stylus laser” clamps a 1 inch polypropylene ball between two plates:

    HQ Sixteen - Stylus Laser - ball clamp test fit
    HQ Sixteen – Stylus Laser – ball clamp test fit

    The plates have a sphere subtracted from them and a kerf sliced across the sphere’s equator for clamping room:

    HQ Sixteen - Stylus Laser Mount - solid model
    HQ Sixteen – Stylus Laser Mount – solid model

    Given that this is a relatively low-stress situation, I embedded BOSL2 nuts to produce threads in the plate rather than use brass inserts.

    The side plates start as simple rectangles:

    HQ Sixteen - Stylus Laser Mount - solid model - mount sides
    HQ Sixteen – Stylus Laser Mount – solid model – mount sides

    Subtracting the electronics pod shape from those slabs matches them exactly to the curvalicious corner:

    HQ Sixteen - Stylus Laser Mount - solid model - mount shaping
    HQ Sixteen – Stylus Laser Mount – solid model – mount shaping

    The weird angle comes from tilting the mount to aim the laser in roughly the right direction when perpendicular to the plates:

    HQ Sixteen - Stylus Laser Mount - solid model - show
    HQ Sixteen – Stylus Laser Mount – solid model – show

    That angle can be 0° to 30°, although 25° seems about right. The slab sides neither stick out the top nor leave gaps in the corner over that range, after some cut-and-try tinkering sizing.

    One of the M3 screws just did not want to go into its hole:

    HQ Sixteen - Stylus Laser - threadless M3 screw
    HQ Sixteen – Stylus Laser – threadless M3 screw

    A bad day in the screw factory, I suppose.

    The OpenSCAD source code as a GitHub Gist:

    // Handiquilter HQ Sixteen Stylus Laser Mount
    // Ed Nisley – KE4ZNU
    // 2025-02-23
    include <BOSL2/std.scad>
    include <BOSL2/threading.scad>
    Layout = "Pod"; // [Show,Build,Pod,Mount]
    /* [Hidden] */
    PodWidth = 110.0; // overall width of pod
    PodScrewClear = 50.0; // clear distance between pod screws
    PodRecenter = [0,0]; // pod trace upper corner to origin if not done in Inkscape
    BaseAngle = -25; // laser neutral angle
    BallOD = 25.4 + 0.2; // bearing ball + easy fit clearance
    BallOffset = [70.0,0,-35.0]; // upper corner to ball center
    LaserOD = 12.2; // laser module
    LaserLength = 38.0;
    Kerf = 1.0; // clamp gap
    Plate = [35.0,35.0,8.0 + Kerf]; // basic mount plate
    WallThick = 5.0; // upright walls: plate to pod
    WasherOD = 7.0;
    ScrewPitch = 0.5;
    ScrewNomOD = 3.0;
    ScrewNomID = ScrewNomOD – ScrewPitch;
    ScrewOC = Plate – [WasherOD,WasherOD,0];
    Gap = 5.0; // build spacing
    //———-
    // HQ Sixteen electronics pod
    module Pod() {
    xrot(90)
    down(PodWidth/2)
    linear_extrude(height=PodWidth,convexity=5)
    translate(PodRecenter)
    import("HQ Sixteeen – pod profile.svg",
    layer="Pod Profile");
    }
    module LaserPointer() {
    cylinder(d=LaserOD,h=LaserLength,center=true);
    }
    module Ball() {
    union() {
    sphere(d=BallOD,$fn=4*12);
    down(0.25*LaserLength)
    LaserPointer();
    }
    }
    module Mount() {
    union() {
    difference() {
    union() {
    cuboid(Plate,anchor=CENTER);
    for (j=[-1,1])
    translate([-(BallOffset.x – Plate.x)/2,j*(Plate.y + WallThick)/2,Kerf/2])
    cuboid([BallOffset.x,WallThick,-0.75*BallOffset.z],anchor=BOTTOM);
    }
    cuboid([4*Plate.x,4*Plate.y,Kerf],anchor=CENTER);
    Ball();
    for (i=[-1,1], j=[-1,1])
    translate([i*ScrewOC.x/2,j*ScrewOC.y/2,0])
    cylinder(d=1.2*ScrewNomOD,h=2*Plate.z,anchor=CENTER,$fn=6);
    yrot(-BaseAngle)
    translate(-BallOffset)
    Pod();
    }
    for (i=[-1,1], j=[-1,1])
    translate([i*ScrewOC.x/2,j*ScrewOC.y/2,Kerf/2])
    // flat size root dia height pitch
    threaded_nut(1.5*ScrewNomOD,ScrewNomID,(Plate.z – Kerf)/2,ScrewPitch,$slop=0.10,
    bevel=false,ibevel=false,anchor=BOTTOM);
    }
    }
    //———-
    // Build things
    if (Layout == "Pod")
    Pod();
    if (Layout == "Mount")
    Mount();
    if (Layout == "Show") {
    yrot(BaseAngle) {
    color("SteelBlue")
    Mount();
    color("Magenta",0.5)
    Ball();
    color("Red")
    yrot(180)
    cylinder(d=2,h=-2*BallOffset.z,$fn=12);
    }
    translate(-BallOffset)
    color("Silver",0.8)
    Pod();
    }
    if (Layout == "Build") {
    left(Plate.x/2 + Gap/2)
    intersection() {
    cuboid([4*Plate.x,4*Plate.y,-BallOffset.z],anchor=DOWN);
    down(Kerf/2)
    Mount();
    }
    right(Plate.x/2 + Gap/2)
    intersection() {
    cuboid([4*Plate.x,4*Plate.y,Plate.z/2],anchor=DOWN);
    up(Plate.z/2)
    Mount();
    }
    }