[User]
Okay, I'm looking to design an SD card holder, and I need something that's easily customizable. I've seen a design on Thingiverse (thing:15323) that's a good starting point, and I even have the OpenSCAD code for that design which is included below. However, I want to make sure the design is fully parametric, and I want to be able to easily control not only the number of slots, but also things like the slot size, separation, and the angle of the top surface.

Here's what I'm thinking:

*   **Basic Shape:** The holder should be a sort of angled block, with the SD card slots cut into the top. The back should be higher than the front due to the angled top surface.
*   **Slots:** I need to specify the number of slots, the width, thickness (front-to-back) and depth of each slot, and the separation between slots.
*   **Dimensions:** I need control over the overall width of the holder, as well as the front and back depth, and the bottom height (distance from the bottom of the first slot to the bottom of the holder).
*   **Top Angle:** The top surface of the holder should rise at an angle from the front to the back. I need to be able to specify that angle.

I want the following parameters to be easily adjustable:

*   `slots`: The number of SD card slots.
*   `slotWidth`: The width of each slot.
*   `slotThickness`: The thickness of each slot (front to back).
*   `slotSeparation`: The distance between each slot.
*   `slotDepth`: How deep the card sits in the slot.
*   `topRiseAngle`: The angle of the top surface from front to back in degrees.
*   `bottomHeight`: The height of the bottom of the first slot from the bottom of the holder.
*   `sideWidth`: The width of the left/right border.
*   `frontDepth`: The distance from the front edge to the first slot.
*   `backDepth`: The distance from the back edge to the last slot.

I'd like the code to define a module called `SDCardHolder()` which will render the card holder using the parameters. The code that I have includes the basic `linear_extrude` command as well as other basic OpenSCAD commands, but I don't need to rely on any external libraries for this specific project.

Could you generate an OpenSCAD file that implements this design? Please make sure it's well-commented and easy to understand.
```
// Parameterized SD card holder, PAmes
//
// Published at:
//    http://www.thingiverse.com/thing:15323
//
// Derivative of http://www.thingiverse.com/thing:9218 by jpcw
//
// Can adjust the number of slots, and the slot size

// The slot, of course, should be a little larger than the card.
// Adjust for desired fit.  I use these numbers on my TOM/Mk7,
// which give a slightly loose fit (the cards will fall out easily
// if turned over).  If you want to adjust the slot size, try
// experimenting by setting 'slots' to 1.
// All units are mm.

slots = 6;  // As many or as few as you want
slotWidth = 26;
slotThickness = 3; // front to back
slotSeparation = 4;  // Barrier between slots
slotDepth = 15; // This much of the card fits into the slot, half of the card height seems about right.
topRiseAngle = 15; // degrees

// These should be OK as is.  Adjust if you want wider borders.
bottomHeight = slotSeparation; // bottom of first hole to bottom of holder
sideWidth    = slotSeparation; // left, right borders
frontDepth   = slotSeparation; // front to first hole
backDepth    = slotSeparation; // back to last hole

// Shouldn't have to mess with these.
holderWidth = slotWidth + 2*sideWidth;
holderFrontHeight = slotDepth + bottomHeight - tan(topRiseAngle)*frontDepth;
holderDepth = frontDepth + slotThickness*slots +
            slotSeparation*(slots-1) + backDepth;
holderBackHeight = holderFrontHeight + tan(topRiseAngle)*holderDepth;

module basicBlock() {
  linear_extrude(height=holderWidth, convexity=2)
    polygon(points = [ [0, 0],
                     [holderDepth, 0],
                     [holderDepth, holderBackHeight],
                     [0, holderFrontHeight] ]);
}

// One slot, at first location
module slot() {
  translate([frontDepth, bottomHeight,0])
    translate([0,0,sideWidth])
      cube(size=[slotThickness, holderBackHeight, slotWidth]); // sticks up, used by difference()
}

// Makes all slots
module slots() {
  for (i = [0 : slots-1]) {
    translate([i*(slotSeparation+slotThickness), i*tan(topRiseAngle)*(slotSeparation+slotThickness), 0])
      slot();
  }
}

// Put it all together
module SDCardHolder() {
  // Place into nice orientation
  rotate([0,0,90])
    translate([-holderDepth/2,holderWidth/2,0])
      rotate([90,0,0])
        difference() {
          basicBlock();
          slots();
        }
}

SDCardHolder();
```

[Assistant]
SD_Holder.scad:
```
// Parameterized SD card holder, PAmes
//
// Published at:
//    http://www.thingiverse.com/thing:15323
//
// Derivative of http://www.thingiverse.com/thing:9218 by jpcw
//
// Can adjust the number of slots, and the slot size

// The slot, of course, should be a little larger than the card.
// Adjust for desired fit.  I use these numbers on my TOM/Mk7,
// which give a slightly loose fit (the cards will fall out easily
// if turned over).  If you want to adjust the slot size, try
// experimenting by setting 'slots' to 1.
// All units are mm.

slots = 6;  // As many or as few as you want
slotWidth = 26;
slotThickness = 3; // front to back
slotSeparation = 4;  // Barrier between slots
slotDepth = 15; // This much of the card fits into the slot, half of the card height seems about right.
topRiseAngle = 15; // degrees

// These should be OK as is.  Adjust if you want wider borders.
bottomHeight = slotSeparation; // bottom of first hole to bottom of holder
sideWidth    = slotSeparation; // left, right borders
frontDepth   = slotSeparation; // front to first hole
backDepth    = slotSeparation; // back to last hole

// Shouldn't have to mess with these.
holderWidth = slotWidth + 2*sideWidth;
holderFrontHeight = slotDepth + bottomHeight - tan(topRiseAngle)*frontDepth;
holderDepth = frontDepth + slotThickness*slots +
            slotSeparation*(slots-1) + backDepth;
holderBackHeight = holderFrontHeight + tan(topRiseAngle)*holderDepth;

module basicBlock() {
  linear_extrude(height=holderWidth, convexity=2)
    polygon(points = [ [0, 0],
                     [holderDepth, 0],
                     [holderDepth, holderBackHeight],
                     [0, holderFrontHeight] ]);
}

// One slot, at first location
module slot() {
  translate([frontDepth, bottomHeight,0])
    translate([0,0,sideWidth])
      cube(size=[slotThickness, holderBackHeight, slotWidth]); // sticks up, used by difference()
}

// Makes all slots
module slots() {
  for (i = [0 : slots-1]) {
    translate([i*(slotSeparation+slotThickness), i*tan(topRiseAngle)*(slotSeparation+slotThickness), 0])
      slot();
  }
}

// Put it all together
module SDCardHolder() {
  // Place into nice orientation
  rotate([0,0,90])
    translate([-holderDepth/2,holderWidth/2,0])
      rotate([90,0,0])
        difference() {
          basicBlock();
          slots();
        }
}

SDCardHolder();

```


[User]
Okay, I've got this idea for a 3D printable hook that uses the keyholes in my boltless shelving units. I'd like to create a parametric OpenSCAD model so I can adjust it to fit different shelves.

Basically, the design needs to have two posts that slot into the keyholes, and these posts need to be connected by a support bar. Then, extending from the support bar, I need a hook shape, a wedge-like design that extends out a bit and curves upwards to form a hook. I'd like to hang things like scissors, headphones, and maybe even small pots from these.

Here are the important parameters I think we need to control:

*   **`key_big`**:  The diameter of the larger round part of the keyhole. I'd need to make this a bit smaller than the actual measurement for clearance.
*   **`key_small`**: The diameter of the smaller, offshoot part of the keyhole.  Also needs to be slightly smaller than the actual.
*   **`key_spacing`**: The distance between the centers of the two keyholes. Make this slightly bigger than the actual for clearances.
*   **`key_thickness`**: The thickness of the shelf material where the keyholes are cut out. This also should be a bit bigger than reality for the model.
*   **`poke`**:  The distance the hook extends out from the support bar - a minimum distance.
*   **`hook`**:  The total height of the hook's tip and is twice the width of the hook. The hook itself will be smaller than `poke`.
*   **`support_thickness`**: The thickness of the support bar connecting the two posts and the lugs that go into the keyholes.

I'd like the posts that fit in the keyholes to be cylindrical. The support bar connecting the two posts should also be rectangular with rounded edges for a good fit, and the connection between the support bar and the posts should be robust. I have a good start on the project and have included the initial code as a reference. It includes a `wedge()` module for the hook and a `betterjoints()` module.  It appears the module `betterjoints()` needs a little more consideration.

I'd like to see some improvement on the structure around the keyhole connection as the model could break at those points, maybe some more overlap with the cylindrical post.

It would be really helpful if the model could be centered on the build platform, I have included a starting point for centering in the current code, but would like to see it improved.

I'm hoping this can be a fully parametric design that I can customize for any boltless shelving.

Is it possible for you to help me generate a parametric OpenSCAD file based on this? I don't need specific libraries mentioned.

[Assistant]
keylock_rail_hook_15515.scad:
```
// for precise messurement points see the supplied pictures

//diameter of the large round part of the key hole,make smaller then real (for clearaces)
key_big = 11;
//diameter of the small offshoot from the main key cylinder,make smaller then real (for clearaces)
key_small = 6;

//distance from one key hole to the same point in the next key hole, make slightly bigger then real (for clearaces)
key_spacing = 39;
//thickness of the material the key holes are kut out of, make slightly bigger then real (for clearaces)
key_thickness = 1.25;

//the distance the hook extends from the support, poke should be bigger then hook
poke = 30;
//total hight if hook tip, hook width will = half this, hook should be smaller then poke
hook = 20;
//thickness of lugs and support bar
support_thickness = 4;

//turning the numbers into what object needs

hookStart = support_thickness*2+key_thickness;
angle = atan ( hook / poke);
hype = poke + hook;
KBR = key_big/2;
KSR = key_small/2;

module wedge()  {
	translate([0,-key_small,0]) difference() {
		cube([poke,key_small,hook]);
		rotate(a=[0,-angle,0])translate([0,-1,0])cube([hype,key_small+2,hook]);
	}	}

module betterjoints() {
	intersection(){
		translate([0,-KSR,0])cube([key_spacing,key_small,support_thickness*2+key_thickness]);
		cylinder(h= support_thickness*2+key_thickness ,r1 = KBR , r2 = KBR,$fn=36);
	}
}

translate([-KBR- key_spacing/2,-KBR,0]) {		//to centre item on the build platform

translate([KBR,KBR - KSR,hookStart]) {		//hook and support bar making section
	cube([hook/2,key_small,poke]);
	rotate(a=[0,270,180]) wedge();
	translate([poke,0,0])rotate(a=[0,0,180]) wedge();
	translate([0,0,-support_thickness]) cube([key_spacing,key_small,support_thickness]);
	}

translate([KBR,KBR,0]) {								//post 1
	cylinder(h= hookStart + poke, r1 = KSR ,r2 = KSR,$fn=36);
	cylinder(h= support_thickness ,r1 = KBR , r2 = KBR,$fn=36);
	betterjoints();
	translate([key_spacing,0,0]){						//post 2
		cylinder(h= hookStart, r1 = KSR ,r2 = KSR,$fn=36);
		cylinder(h= support_thickness ,r1 = KBR , r2 = KBR,$fn=36);
		betterjoints();
		}
	}
}
```


[User]
Okay, I've got a design for an Arduino battery clip that I've been working on, but it's a bit clunky and I'd like to make it more parametric so it's easier to adjust for different boards and battery types.

Right now, it's designed to screw onto the bottom of a standard Arduino, and hold a 9V battery. It mostly works for UNOs, Duemilanoves, etc., and even MEGA boards, but I want to be able to tweak things easily.

Here's what it does currently:

*   It has a base plate that sits under the Arduino board, with screw holes that line up with the mounting holes.
*   It has arms that extend out to attach to the board and for mechanical stability, and some support pegs (leg) that are vertical to make the piece stable when sitting on a flat surface.
*   It has a battery clip on one side that holds a standard 9V battery.
*   It includes an option to add some washers/spacers underneath the base plate.

Here's what I'd like the parametric design to handle:

1.  **Board Dimensions:** I need to be able to adjust the dimensions of the main board (length, width, and thickness), as the "standard" Arduino size isn't always used. Also, the relative distances from the center to the screw holes are important parameters that I want to easily adjust.
2.  **Screw Hole Placement and Diameter:** Right now, the screw holes are hardcoded, but I need to be able to specify the number of screw holes, their diameter, and their locations relative to the center of the base plate. The file I've attached currently includes the screw diameter as `screw_r` which works for now. The default value is set based on the M3 screws that I use.
3.  **Arm Placement:** The current arm placement is also hardcoded, and I would like to have the ability to move each arm to different (x,y) locations based on the central reference of the base board.
4.  **Arm Dimensions:** The arms are cylinders with a center "bridge" and I would like to adjust all of these dimensions parametrically: arm length/ width, cylinder radius, and bridge length/width. Also, I'd like to maintain the "leg" as well, if possible, and also be able to turn it off.
5.  **Battery Clip Dimensions:** I need to be able to adjust the width, length, and height of the battery clip itself. This will allow me to adapt it to different battery types.
6.  **Washer/Spacer Options:** I'd like to keep the washer functionality but ideally I want to be able to set the number of rows and columns of washers, and the diameter, height, and relative positions of the washer.
7.  **General Thickness:** It would be great to have a base thickness parameter, that sets the thickness of the baseplate.

I want to make sure the code is clear and well-commented so it's easy to understand. I'm using OpenSCAD, so the output needs to be a `.scad` file. I'd also appreciate it if the design uses the `MCAD` library for common shapes, if possible (I am not claiming that the code below currently uses any libraries, just to clarify).

Please create this parametric OpenSCAD design for me. I've attached my current `Arduino_Battery_Clip.scad` as a starting point so you can see how I've set things up. I am not expecting the same exact layout to be preserved.

[Assistant]
Arduino_Battery_Clip.scad:
```
UNO=false;
washers=true;
thickness=5;
width=7;

cX=53.3/2;
cY=68.6/2;
screw_r=3.2/2;

mainClip();

module washers(arrayLength,arrayWidth,washerLength,washerWidth,resolution){
  for(i=[-(arrayLength-1)/2:(arrayLength-1)/2]){
    for(j=[-(arrayWidth-1)/2:(arrayWidth-1)/2]){
      translate([i*10,j*10,0]){
        washer(washerLength,washerWidth,resolution);
      }
    }
  }
}

module washer(length,width,resolution){
  translate([0,0,length/2]){
    difference(){
      cylinder(r=width/2,h=length,center=true,$fn=resolution);
      cylinder(r=screw_r,h=length,center=true,$fn=resolution);
    }
  }
}

module mainClip(){
  translate([0,0,thickness/2]){
    cube([38.3,25,thickness],center=true);
  }
  batteryClip(0,thickness,true);
  arm(0,0,-(cX-7.6)+3.5,cY-2.5,width,thickness,0,100,true,false,1,-1);
  if(UNO) arm(0,0,-(cX-2.5),-(cY-14),width,thickness,0,100,true,false,1,1);
  arm(0,0,cX-15.2,cY-2.5,width,thickness,0,100,true,false,-1,-1);
  arm(0,0,cX-2.6+1.5,-(cY-15.3)-1.5,width,thickness,0,100,true,false,-1,1);
  if(washers){
    for(i=[-1.5:1.5]){
      translate([-25,5+i*8,0]){
        washer(5,width,100);
      }
    }
  }
}

module arm(startX,startY,endX,endY,width,height,zOffset,resolution,hole,leg,xs,ys){
  if(hole){
    difference(){
      armWithoutHole(startX,startY,endX,endY,width,height,zOffset,resolution,leg,xs,ys);
      translate([endX,endY,zOffset+height/2]){
        cylinder(r=screw_r,h=height,center=true,$fn=resolution);
      }
    }
  }else{
    armWithoutHole(startX,startY,endX,endY,width,height,zOffset,resolution,leg,xs,ys);
  }
}

module armWithoutHole(startX,startY,endX,endY,width,height,zOffset,resolution,leg,xs,ys){
  translate([startX,startY,zOffset+height/2]){
    cylinder(r=width/2,h=height,center=true,$fn=resolution);
  }
  translate([endX,endY,zOffset+height/2]){
    cylinder(r=width/2,h=height,center=true,$fn=resolution);
  }
  len=sqrt(pow(startX-endX,2)+pow(startY-endY,2));
  translate([(startX+endX)/2,(startY+endY)/2,zOffset+height/2]){
    rotate([0,0,-atan((startX+endX)/(startY+endY))]){
      cube([width,len,height],center=true);
    }
  }
  if(leg){
    translate([
        endX+((thickness)/(xs*sqrt((((startY-endY)*(startY-endY))/((startX-endX)*(startX-endX)))+1))),
        endY+((thickness)/(ys*sqrt((((startX-endX)*(startX-endX))/((startY-endY)*(startY-endY)))+1))),
        12.5+height
      ]){
      cylinder(r=thickness/2,h=25,center=true,$fn=resolution);
    }
  }
}

module batteryClip(xOffset,zOffset,center){
  xOffset = center? 76.7/2+xOffset: xOffset;
  //zOffset=0;

  batteryw = 25.4;
  batteryh = 16.4;
  ClipW = 6.5;  //width of the clip
  ClipL = 25; //length of the clip

  //internal constants
  dimh = 4.242641;  // dimensions of the 3 cube after rotating 45 degrees

  translate([xOffset/2 - batteryw/2 -ClipW ,0,0]){
    union(){
      translate([batteryw/2,0-ClipL/2,zOffset]) {
        cube ([ClipW, ClipL, batteryh+dimh/2]);
        translate([0-dimh/2,0,batteryh]){
          rotate([0,45,0]){
            cube([3,25,3]);
          }
        }
      }
      rotate (a = [0,0,180]){
        translate([batteryw/2,0-ClipL/2,zOffset]) {
          cube ([ClipW, ClipL, batteryh+dimh/2]);
          translate([0-dimh/2,0,batteryh]){
            rotate([0,45,0]){
              cube([3,25,3]);
            }
          }
        }
      }
    }
  }
}

```


[User]
Okay, I'm looking to design a printable linear bushing for a 6mm rod, similar to the LM6UU standard, but with some flexibility in the design. I've got an existing OpenSCAD file that I've been playing with (attached), but it's getting a bit messy and I want to make it more parametric and easier to customize.

Here's what I'm looking for:

**Core Functionality:**

*   **LM6UU Compatibility:** The core design should be for a 6mm inner diameter rod (that's the `id` parameter in the attached file) and should have a nominal 12mm outer diameter (`od` in the file) and a length of 19mm (`length` in the file). These dimensions need to be configurable so I can easily create different sizes (e.g. for an LM8UU or other custom sizes).
*   **Internal Ribs:** The bushing should have internal ribs that grip the rod. I'd like to be able to control the number of ribs (`n` in the file) and the height of these ribs (related to `id_clearance`). The rib design in the existing file uses a twisted extrusion, I would like to keep that general design of ribs.
*   **Open Bearing Option:** I need a parameter (`open`) to create an open linear bearing, with a 60 degree cutout on one side to allow for an open bearing design.

**Parametric Control:**

*   **Inner Diameter (`id`)**:  The inner diameter of the bushing, where the rod slides through.
*   **Outer Diameter (`od`)**: The outer diameter of the bushing.
*   **Length (`length`)**: The length of the bushing.
*  **External Clearance (`clearance`)**:  This parameter dictates an outer clearance to account for the nominal sizes.
*   **Number of Ribs (`n`)**:  The number of internal ribs.
*   **Rib Clearance/Height (`id_clearance`):**  The radial clearance between the ID and the top of the ribs.
*   **Open Bearing Toggle (`open`)**: A boolean to enable/disable the 60 degree cutout for open bearing designs.
*  **Layer Height (`layer_height`)** This parameter should be a scalar value to help with calculating the twist of the ribs. This is important to maintain the correct twists for different printers.

**Features I'd Like:**

*   **Top and Bottom Chamfers/Countersinks:** I'd like to add chamfers or countersinks to the top and bottom of the bushing for better entry of the rod. The existing file has some elements that look like this using `cylinder` primitives, they can be a starting point.
*   **Clear and Well-Documented Code:** The code should be well organized and commented for easy understanding and future modification.
*   **Use of Libraries:** If necessary, use the MCAD library.

**What I need:**

I'd like a new OpenSCAD file that incorporates all of these features with clear, well organized code. I'm looking to make this as parametric and easy to use as possible.

Let me know if you have any questions or need additional clarification.

[Assistant]
printable-lm6uu.scad:
```
// Based on http://www.thingiverse.com/thing:13631 by Triffid Hunter
// 2012-01-24
// Modified for LM6UU, open bearing, and  options

// preview[view:north, tilt:top]

// Nominal Sizes:

// Internal Diameter
id= 6; // [0:30]

// External Diameter
od= 12.0; // [0:30]

// Length
length = 19;  // [0:40]

//  lm6uu id, od, length are nominally 6,12,19
// lm8uu are 8 16.0 25

// External Clearance
clearance=1; [0:5]

lm8uu_id=id-0.8;  // ???
lm8uu_od=od-clearance;
lm8uu_length = length -clearance;

// Open a 60 degree slot
open=0;  // [0:closed,1:open]  // cut a 60 degree slot out of the side for an open bearing

// rib height
id_clearance = 1; // [0:5]

// number of ribs
n = 5; //[0:10]

// Layer height (for computing twisted ribs)
layer_height = 0.2;

// Facets
$fn=32;

//!plate();
!bushing();

module plate(ii=3,jj=4,spacing=4){
  interval=lm8uu_od+spacing;
  for ( i = [0 :  ii -1 ]) {
    for (j = [0 : jj -1 ]) {
    translate([i*interval,j*interval,0]) bushing();
   }
  }
}

module bushing() {
difference() {
	cylinder(r=lm8uu_od / 2, h=lm8uu_length - layer_height);
	difference() {
		cylinder(r=lm8uu_id / 2 + id_clearance, h=lm8uu_length - layer_height);
		linear_extrude(height = lm8uu_length - layer_height, twist = 540 / n, slices = (lm8uu_length - layer_height))
			for (i=[0:360/n]) {
				rotate(360 / n * i)
					translate([lm8uu_id / 2 / sqrt(2), lm8uu_id / 2 / sqrt(2)])
						square([lm8uu_id, lm8uu_id]);
			}
	}
	translate([0, 0, -1 + layer_height])
		cylinder(r1=lm8uu_id / 2 + id_clearance + 1, r2=0, h=lm8uu_id / 2 + id_clearance + 1);
	translate([0, 0, lm8uu_length - layer_height * 2 - (lm8uu_id / 2 + id_clearance)])
		cylinder(r2=lm8uu_id / 2 + id_clearance + 1, r1=0, h=lm8uu_id / 2 + id_clearance + 1);
	translate([0, 0, -1])
		cylinder(r=id/2, h=lm8uu_length + 2);
    if(open) {
	     rotate(360/5+5) translate([0, lm8uu_od/2, -1]) rotate(30) cylinder($fn=3,r=lm8uu_od/2,h=lm8uu_length+2);

	}
}
}

```


[User]
Okay, I'm looking to create a parametric fan grill for an 80mm fan, and I'd like to be able to customize it for different fan sizes. I've seen a design on Thingiverse ([thing:15785](https://www.thingiverse.com/thing:15785)) which is close to what I want, and have a slightly modified version that I've attached called `fan_grill.scad`. However, I'd like to generate a similar OpenSCAD design that is a little more robust and also a little easier to understand and modify.

Here's what I'm looking for:

**Overall Design:** I want a square fan grill with rounded corners. It should have a main square body with a circular hole in the center. There should be screw holes for mounting the fan. The grill itself should be made of a series of radiating spines.

**Parametric Controls:** I'd like to be able to control the following:

*   **Fan Size:** This would be the overall size of the grill (currently `size`). It should determine the outer dimensions of the square and the diameter of the central hole.
*   **Border Thickness:** The width of the solid border around the edge of the grill (currently `borderthickness`).
*   **Corner Radius:** How rounded the corners of the grill are (currently `cornerradius`).
*   **Sheet Thickness:**  The overall thickness of the grill (currently `thickness`).
*   **Screw Radius:** The radius of the screw holes (currently `screwradius`).
*   **Screw Inset:**  The distance the screw holes are set in from the corners of the grill (currently `screwinset`).
*   **Number of Spines:** The number of radiating spines within the circular hole (currently `spines`).
*   **Spine Thickness:**  The thickness of each spine (currently `spinesize`).
*   **Spine Offset:** How far away from the center circle the spine starts (currently `spineoffset`). This is a difficult one to visualize. Perhaps there's a better way to describe how the spines are positioned, but right now this parameter works.
*  **Spine Rotation:**  An extra rotation of all the spines (currently `spinerotation`).

**Specific Design Requirements:**

*   The central hole should be calculated based on the fan size and border thickness.
*   Screw holes should be placed at the four corners, and the centers should be inset from the corners.
*   The radiating spines should extend from their offset to the central hole. They should all be the same size, thickness, and symmetrically placed around the circle.

**OpenSCAD Specific Requirements**
* The code should be well commented to explain the purpose of each section and parameter.
* I would prefer to avoid `translate()` operations where possible. Please use `rotate()` and `linear_extrude` or `polygon` type objects where possible to generate the spines.
* Please use descriptive variable names.
*   I'd like to use the `MCAD` library if possible to generate the rounded edges, so I would not need the `cube` + `cylinder` hacks for the corner.

**Output:**
* The output should be a single `.scad` file. It should generate a solid model of the fan grill suitable for 3D printing.

I think that covers it. Let me know if you need any further clarification. Thanks!

[Assistant]
fan_grill.scad:
```
/* [Body Parameters] */
// Fan Size
size=80;
// Border Width
borderthickness=5;
// Corner Radius
cornerradius=4;
// Sheet Thickness
thickness=2;

/* [Screw Hole Parameters] */
// Screw Radius
screwradius=2.3;
// Screw Inset From Corder
screwinset=4;

/* [Spine Parameters] */
// Number of Spines
spines=10;
// Spine Thickness
spinesize=2;
// Spine Offset from center
spineoffset=10;
// Spine Extra Rotation
spinerotation=0;

/* [Hidden] */
dxf=false;
// Below are not parameters //

// Calculate helper variables
holeradius=size/2-borderthickness;

// Create the grill
if (dxf)
	projection(cut=false) fan_grill();
else
	fan_grill();

module fan_grill()
{
	union()
	{
		difference()
		{
			body();

			// hole
			translate([size/2,size/2,-thickness/4]) cylinder(r=holeradius,h=thickness*2);

			// screws
			translate([screwinset,screwinset,0]) cylinder(r=screwradius,h=thickness);
			translate([screwinset,size-screwinset,0]) cylinder(r=screwradius,h=thickness);
			translate([size-screwinset,screwinset,0]) cylinder(r=screwradius,h=thickness);
			translate([size-screwinset,size-screwinset,0]) cylinder(r=screwradius,h=thickness);
		}
		translate([size/2,size/2,0])
		interrior();
	}
}

module body()
{
	union()
	{
		translate([0,cornerradius,0]) cube(size=[size,size-(cornerradius*2),thickness]);
		translate([cornerradius,0,0]) cube(size=[size-(cornerradius*2),size,thickness]);
		translate([cornerradius,cornerradius,0]) cylinder(r=cornerradius,h=thickness);
		translate([cornerradius,size-cornerradius,0]) cylinder(r=cornerradius,h=thickness);
		translate([size-cornerradius,cornerradius,0]) cylinder(r=cornerradius,h=thickness);
		translate([size-cornerradius,size-cornerradius,0]) cylinder(r=cornerradius,h=thickness);
	}
}

module interrior()
{
	for(i=[0:spines-1])
	{
		  rotate(a=[0,0,i*(360.0/spines)+spinerotation])
		  translate([spineoffset,-spineoffset/3.141,0])
		  cube([spinesize,holeradius+(spineoffset/3.141),spinesize]);
	}
}
```


[User]
Okay, I'm looking to create some collets for a tap holder, similar to what's described in the Thingiverse project 16956 (and its derivatives). I need a parametric OpenSCAD file that allows me to generate collets for both cylindrical (drill bits) and hexagonal (accessories) shanks.

Here's what I need the design to be able to handle:

**Overall Collet Structure:**

*   The collet will have a basic cylindrical body with three sections:
    *   A main cylindrical section.
    *   A tapered transition from the main cylinder to a smaller cylinder.
    *   A second taper to a smaller cylinder, which is intended to be clamped.
*   The collet should have multiple openings (slits) along its length to allow it to compress and grip the shank. I need to control the number of these openings.

**Parameters I want to control:**

1.  **`typ` (Type):**  This parameter should switch between "C" for cylindrical and "H" for hexagonal.

    *   **Cylindrical (`typ = "C"`):**
        *   **`dbd` (Drill Bit Diameter):** The diameter of the drill bit the collet is intended for.
    *   **Hexagonal (`typ = "H"`):**
        *   **`f2f` (Face to Face):** The distance between opposite faces of the hexagon.
        *   **`ffn` (Faces Number):**  Always 6 for a hexagon, but the parameter needs to be there in the script.
        *   **`fop` (Face Opening):**  Defines where the openings are cut. Should be either "V" for vertex or "F" for face, to change which side of the hexagon the openings are cut at.
        *    **`fvs` (Vertex Side length):** The side length of a cube used to exaggerate the cuts, where `fop` is set to "V".

2.  **Common Parameters (used in both `typ` options):**
    *   **`gap`:** Tolerance between the bit diameter (or hex size) and the collet bore, which can be used to control fit, i.e. make the bore slightly larger.
    *   **`ono`:** The number of openings/slits/clamps.
    *   **`omn`:** Minimum size to keep the openings, used to avoid the walls from fusing together when printing.

**Specific Functionality:**

*   **Cylindrical Collet (`typ = "C"`):**
    *   The bore for the drill bit should be slightly smaller than the `dbd` plus `gap` at the start, expanding to `dbd` plus `gap` through the main body of the collet, then expanding again further out.
    *   The `cfn` (number of facets of the cylinder) should be calculated, with `cfn=ono*round(dbd*PI/ono)`.
    *   The openings should be rectangular, and cut out of the main body of the collet.
*   **Hexagonal Collet (`typ = "H"`):**
    *   The bore for the hex shank should be slightly smaller than `f2f` converted to diameter `fod` with the sine function, and an added `gap`, at the start, expanding to `fod` plus `gap` through the main body of the collet, then expanding again further out.
    *  The openings should be rectangular, and cut out of the main body of the collet.
        *   If `fop` is "V", the openings should be at the vertices of the hexagon, exaggerated with a cube as in the original code.
        *   If `fop` is "F", the openings should be at the center of the faces of the hexagon.

**General Notes:**

*   I'd like the code to be well-commented, following general Openscad coding practices.
*   I do not need any MCAD libraries.

Basically, I need a parametric version of what is in `collets4tapHolder.scad`. I'm mainly going to be printing these on my 3D printer so I am not concerned about any manufacturing specific concerns other than the tolerance with the `gap`.

Can you create an OpenSCAD file for this?

[Assistant]
collets4tapHolder.scad:
```
/*
 * collets4tapHolder.scad
 *
 * Written by aubenc @ Thingiverse
 *
 * http://www.thingiverse.com/thing:16956
 *
 * This script is licensed under the
 * Attribution - Share Alike license
 *
 * This is a derivative work of "Tap holder" by Rasle500
 *
 *		http://www.thingiverse.com/thing:16682
 *
 * ...and the derivatives of that work:
 *
 *		http://www.thingiverse.com/thing:16839
 *		http://www.thingiverse.com/thing:16890
 *
 * Usage:
 *
 *    Set the parameters for the desired output, run the required module(s),
 *		render to check, compile and export to STL when/if satisfied.
 *
 */

/* *************** Parameters *********************************************** */

typ="H";		// "C" - Cylindrical, Drill Bit / "H" - Hex, Accessoire

// Parameters for type "C"

dbd=3.2;		// Drill Bit Diameter

// Parameters for type "H"

f2f=6.25;	// Distance between opposite faces
ffn=6;		// Faces number, should NOT work for any value but 6 (hex)
fop="V";		// opening at... "V" - Vertex / "F" - Face
fvs=0.5;		// Side length of the cube used to exagerate the cut for the vertex

// Common Parameters

gap=0.25;	// ...gap ...tolerance ... ... ...
ono=3;		// Number of openings, cuts, clamps, whatever
omn=0.5;		// Minimum size to keep it open (avoid the walls fusing together)

/* *************** Modules ************************************************** */

 collet(typ);

/* *************** Code ***************************************************** */

module collet(typ)
{
	difference()
	{
		body();

		if( typ == "C" )
		{
			drill_bit();
			openings();
		}
		else if( typ == "H" )
		{
			union()
			{
				accessoire_bit();

				if( fop == "V" )
				{
					openings();
				}
				else if ( fop == "F" )
				{
					rotate([0,0,360/ffn/2]) openings();
				}
			}
		}
	}
}

module body()
{
	union()
	{
		cylinder(h=31.25, r=13.75/2, $fn=13.75*PI, center=false);

		translate([0,0,10])
		cylinder(h=31.25-10, r1=13.75/2, r2=15/2, $fn=13.75*PI, center=false);

		translate([0,0,10])
		cylinder(h=31.25-10-4, r1=13.75/2, r2=20/2, $fn=13.75*PI, center=false);
	}
}

module drill_bit()
{
   cfn=ono*round(dbd*PI/ono);

	union()
	{
		translate([0,0,-0.1])
		cylinder(h=10+0.2, r=(dbd-gap)/2, $fn=cfn, center=false);

		translate([0,0,7])
		cylinder(h=31.25-7+0.2, r=(dbd+gap)/2, $fn=cfn, center=false);

		translate([0,0,8.5])
		cylinder(h=8, r=(dbd+gap+1)/2, $fn=cfn, center=false);

		translate([0,0,8.5+8])
		cylinder(h=0.75, r1=(dbd+gap+1)/2, r2=(dbd+gap)/2, $fn=cfn, center=false);
	}
}

module openings()
{

	oy=dbd/ono > omn ? dbd/ono : omn;

	translate([0,0,9.5])
	for(i=[0:ono-1])
	{
		rotate([0,0,i*360/ono])
		translate([6,0,31.25/2])
		cube(size=[12,oy,31.25], center=true);
	}
}

module accessoire_bit()
{
	lf=360/ffn;
	fod=f2f/sin(lf);

	union()
	{
		translate([0,0,-0.1])
		cylinder(h=31.25+0.2, r=(fod+gap)/2, $fn=ffn, center=false);

		translate([0,0,8.5])
		cylinder(h=8, r=(fod+gap+1)/2, $fn=ffn, center=false);

		translate([0,0,8.5+8])
		cylinder(h=0.75, r1=(fod+gap+1)/2, r2=(fod+gap)/2, $fn=ffn, center=false);

		if( fvs != 0 )
		assign(xd=(fod+gap+fvs)/2-(fvs*cos(lf)/2/sin(lf))-0.05)
		{
			for(i=[0:ffn-1])
			assign(x=xd*cos(i*lf), y=xd*sin(i*lf))
			{
				translate([x,y,31.25/2+0.75])
				rotate([0,0,i*lf])
				cube([fvs,fvs,31.25], center=true);
			}
		}
	}
}
```


[User]
Okay, I need some help designing a more advanced measuring cup. I’ve made a very basic one, but I’d like to make it more customizable and robust, and a little nicer looking.

Here's what I currently have (attached: `measuring_cup.scad`). It's functional but quite simple:

*   **Functionality:** It calculates the dimensions of a cup based on a target volume, specified as a sum of cups, tablespoons, teaspoons, and milliliters. It uses a cylinder with a slight taper for the cup shape. It also uses a Minkowski sum to create the wall thickness, which is a fixed amount.
*   **Limitations:** The cup shape is very basic and not user-friendly. There are no handles or spouts. The base is a bit thin, and the top edge is very sharp. And all the unit conversions are embedded in the code instead of using a standard library. I'd also like to be able to adjust the taper/shape more.

Here’s what I’d like the new design to accomplish:

1.  **Parametric Volume Input:** I want to be able to specify the target volume in a more user-friendly way. Specifically, I want to be able to enter a target volume in milliliters (mL) and have the cup scale accordingly. I'd like it to also optionally still support cups, tablespoons, and teaspoons in the future, but the calculation should be done using a library and/or well-defined standard conversions.
2.  **Refined Cup Shape:**
    *   **Taper Control:** Instead of just scaling a cylinder, I'd like to be able to control the amount of taper between the base and the top of the cup. I think this could be done by scaling radius values at different heights.
    *   **Curved Base:** Instead of a sharp flat cylinder base, I’d like a rounded interior base for easier cleaning.
    *   **Rounded Top Lip:** I'd like the top edge of the cup to be rounded (perhaps using a torus or some similar technique), making it more comfortable to use.
3.  **Handle:** I’d like to add a simple handle that's also parametric in terms of size and position, and perhaps can even have an opening.
4.  **Spout:** I’d like an option to add a spout. This would be a simple triangular cutout at the top of the cup rim.
5.  **Robust Base:** I would like the base to be thicker (but still be rounded as described above for the interior).
6.  **Wall Thickness:** I’d still like a parametric wall thickness, similar to the original design.
7.  **Unit Testing:** Can you include a way to verify the generated volume of the cup is correct? Ideally this would be something like a `check_volume` function that uses an integration calculation to estimate the volume based on the solid definition, and then compares to the target volume.

Here are my additional requests, in addition to the above features:

*   **Use of Libraries:** Please use the MCAD library for standard conversions (specifically to use the `standard_measures` library for unit conversions) and common math functions. Don't use libraries if they're not required (so you don't need any libraries for drawing shapes).
*   **Commented Code:** Please comment the code clearly to explain how all parts of the design work.
*   **Customization:** The design should allow me to easily modify all the parameters such as wall thickness, handle size, taper, and spout dimensions.

I hope this is enough information, let me know if you need any clarification. Thanks for your help!

[Assistant]
measuring_cup.scad:
```
//Code by Griffin Nicoll 2012

//Stuff to edit! volume is summed so only add what you want
cups = 1;
tbsp = 0;
tsp = 0;
mL = 0;
wall = 1.6; //wall thickness

//stuff you don't need to edit
sq = 1.2; //squeeze
sh = 0.16; //shear
pi = 3.14159;
volume = cups*236588+tbsp*14787+tsp*4929+1000*mL;//mm^3

difference(){
	minkowski(){
		cylinder(r1=0,r2=wall,h=wall,$fn=6);
		cupBase(volume);
	}
	translate([0,0,wall])cupBase(volume);
}
module cupBase(volume){
	x = pow(volume/(570*pi),1/3);
	multmatrix(m=[
		[sq, 0, sh, 0],
		[0, 1/sq, 0, 0],
		[0, 0, 1, 0],
		[0, 0, 0,  1]])
	cylinder(h=10*x,r1=6*x,r2=9*x,$fn=64);
}
```


[User]
Okay, so I've been playing around with this iCube design by Buback, and I'm really liking the idea of a parametric version where I can just specify the size of the cube and everything else scales with it. I found some code online that does this using the iPhone model from Sorup, but I want to be able to control which parts of the phone get included within the iCube. Right now, the code just dumps the entire phone on one of the faces, and it's not quite what I'm envisioning.

Here's what I'm looking for in this parametric iCube:

1.  **Parametric Cube Size:** I want to define a variable, like "cube\_size," that controls the overall size of the cube. Everything else should scale relative to this cube size.

2.  **Optional iPhone Features:** Instead of just having the whole iPhone model jammed in there, I'd like to be able to choose which features of the iPhone are rendered on the cube. I should be able to independently toggle the display of:
    *   The front speaker and home button.
    *   The screen, proximity sensor, front camera, back camera, and flash (essentially, all the flush components).
    *   The side mute switch and volume buttons.
    *   The sim slot, bottom speaker/mic cutouts, headphone jack, top mic.
    *   The connector at the bottom.

3.  **Independent Feature Placement:** The original code just translates the iPhone model to be on the front face. I want a way to specify which face of the cube each group of iPhone features will be placed on (e.g., front, back, left, right, top, bottom).

4.  **Basic scaling:** The scaling for the iphone features should scale up or down based on the cube size such that when the cube is at the size 300, the phone model should be roughly the same size that it is now. I want the iPhone features to remain roughly the same relative size to the cube they are on, even as the cube changes.

5.  **Use existing iPhone model:** I want to continue to use the `iphone4_model.scad` file. I know that it uses rounded rectangles for some things.

Essentially, I'd like a more flexible and customizable version of this parametric iCube. I'm not sure how to best handle this in OpenSCAD, but I'm hoping you can help me write a parametric OpenSCAD file to handle this functionality.

The existing files I'm using are included, however the `iphone4_model.scad` file is a standalone file, not part of a library. I expect that I have to provide that file in the same folder as the generated .scad file.

[Assistant]
parametric_icube.scad:
```
/*
Parametric iCube
Originally designed by Buback as thing:18670
Uses Sorup's openscad iphone if you have it thing:12879
Coded by Ben Rockhold in 2012
*/

// Change this line to fit the cube to YOUR needs!
size=300;

iCube(size);

module iCube(size){
	cube(size,center=true);
}

use<iphone4_model.scad>;
iPhone();

module iPhone(){
translate([0,0,size/2])iphone4(true, true, true, true, true, [0,.7,0]);
}
```
iphone4_model.scad:
```
//Safety = used for padding to avoid deletion with two overlapping surfaces
safety = 2;

//Quality - edges used for circles etc.
// Extra quality used for extreme geometries (the circle that makes the button)
quality = 30;
extra_quality = 30;

//shading factor - when doing single color version, some elements will be shown shaded for visibility
shadingFactor = 0.8;

//How deep a should flush compenent be embedded in the design?
flushEmbed = 3;

//Element corner radius for small elements with rounded corners
elementCornerRadius = 1;

//glass thickness
glassThick = 1.59;

//bevel size
bevel = 0.6;

// Layer dimensions
glassDepth = 9.34;
steelHeight =115.15;
steelWidth=58.55;
steelDepth=glassDepth - 2* glassThick;
glassHeight  = steelHeight - 2 * bevel;
glassWidth  = steelWidth-2 * bevel;

echo(glassHeight);
echo(glassWidth);

frontColor = [0, 0, 0];
sideColor = [0.6, 0.6, 0.6];

//corner
cornerRadius = 8.77;

//front speaker
frontSpeakerWidth = 11.20;
frontSpeakerHeight = 2.7;
frontSpeakerVerticalCenter = 10.35;
frontSpeakerDepth = 2;
frontSpeakerColor = [0.25, 0.25, 0.25];

//button
frontButtonVerticalCenter = 104.79;
frontButtonRadius = 11.20/2;
frontButtonDepth = 1;
frontButtonColor = [0.25, 0.25, 0.25];
//Calculus to make a sphere to get the right button look
frontButtonSphereRadius = (pow(frontButtonRadius,2) / frontButtonDepth) ;

//Proximity Sensor
proximityHeight = 1.20;
proximityWidth = 5.86;
proximityVerticalCenter = 5.25;
proximityColor = [.1, .1, .1];

//camera
backCameraCenter = 8.77;  //Both vertical and horizontal
backCameraRadius = 6.92/2;
backCameraColor = [.30,.30,.30];

//flash
flashVerticalCenter= backCameraCenter;
flashHorizontalCenter = 14.91;
flashRadius = 2.91/2;
flashColor = [.70,.70,.70];

//front camera
frontCameraVerticalCenter = frontSpeakerVerticalCenter;
frontCameraHorizontalCenter = 39.28;
frontCameraRadius = 3.68/2;
frontCameraColor = backCameraColor;

//screen
screenHeight = 74.88;
screenWidth = 49.22;
screenVerticalDistance = 20.13;
screenHorizontalDistance = 4.32+ screenWidth;
screenColor = [.1, .1, .1];

//mic & speaker
bottomMicSpeakerHeight = 5.82 - 3.52;
bottomMicSpeakerWidth = 51.26 - 44.28;
bottomMicSpeakerLeftHorizontalDistance = 51.26;
bottomMicSpeakerRightHorizontalDistance = 15.27;
bottomMicSpeakerDepth=frontSpeakerDepth;
bottomMicSpeakerColor = frontSpeakerColor;

//Sim slot
simVerticalDistance = 52.01;
simWidth = 69.98 - 52.01;
//simFrontDistance = 3.52;
simHeight = 5.83 - 3.52;
simColor = [.70,.70,.70];

//jack
jackHorizontalDistance = 46.51;
jackRadius = 5 / 2;
jackDepth = 10;
jackColor = [0.25, 0.25, 0.25];

//top mic
topMicHorizontalDistance = 41.82;
topMicRadius = 0.9 / 2;
topMicDepth = 2;
topMicColor = jackColor;

//Connector
//connector_edge_distance = 3.14;
connectorHeight = 6.20 - 3.14;
connectorWidth = 40.28 - 18.27;
connectorDepth = 4;
connectorColor = jackColor;

//Mute switches
muteDepth =0.63;
muteTop = 10.17;
muteHeight = 16.13-muteTop;
muteWidth=6.17-3.17;
muteSlotColor=[.8,0,0];
muteButtonColor=sideColor;

//Up/down switches
upDownDepth = 0.58;
upDownRadius = 4.8 / 2;
upCenter = 24.63;
downCenter = 34.92;
upDownColor = sideColor;

//sleep button
sleepHorizontalDistance = 19.54;
sleepWidth = sleepHorizontalDistance- 9.44;
sleepHeight = 6.17 - 3.17;
sleepDepth = 0.58;
sleepColor =[.75,.75,.75];

//show_flush - show/hide all flush components e.g. camera, flash, scren
//show_buttons - show side buttons
//show_front - show front items - button and speaker
//show_connector - show connector
//show_misc_side - show misc side items, speaker, mic, sim etc..
//singleColor - select which color to paint the entire phone to make it easy to see in drawings

iphone4(true, true, true, true, true);
translate([0, 70, 0]) iphone4(true, true, true, true, true, [0,.7,0]);

module iphone4(show_connector=false, show_buttons=false, show_front=false, show_flush=false, show_misc_side=false, singleColor=[-1, -1, -1]) {
	// Generate shaded color for single color use (which is really dual color)
	shadedSingleColor = singleColor*shadingFactor;

	//Color mingling - if no color is given we represent a fairly realistic view
	frontColor = singleColor[0] == -1 ?  frontColor : singleColor;
	sideColor = singleColor[0] == -1 ? sideColor :singleColor;
	frontSpeakerColor = singleColor[0] == -1 ?  frontSpeakerColor : shadedSingleColor;
	frontButtonColor = singleColor[0] == -1 ?  frontButtonColor: shadedSingleColor;
	proximityColor = singleColor[0] == -1 ?  proximityColor : shadedSingleColor;
	backCameraColor = singleColor[0] == -1 ?  backCameraColor : shadedSingleColor;
	flashColor = singleColor[0] == -1 ?  flashColor : shadedSingleColor;
	frontCameraColor = singleColor[0] == -1 ?  frontCameraColor : shadedSingleColor;
	screenColor = singleColor[0] == -1 ?  screenColor : shadedSingleColor;
	bottomMicSpeakerColor = singleColor[0] == -1 ?  bottomMicSpeakerColor : shadedSingleColor;
	simColor = singleColor[0] == -1 ?  simColor : shadedSingleColor;
	jackColor = singleColor[0] == -1 ?  jackColor : shadedSingleColor;
	topMicColor = singleColor[0] == -1 ?  topMicColor : shadedSingleColor;
	connectorColor = singleColor[0] == -1 ?  connectorColor : shadedSingleColor;
	muteSlotColor = singleColor[0] == -1 ?  muteSlotColor : shadedSingleColor;
	muteButtonColor = singleColor[0] == -1 ?  muteButtonColor : shadedSingleColor;
	upDownColor = singleColor[0] == -1 ?  upDownColor : shadedSingleColor;
	sleepColor = singleColor[0] == -1 ?  sleepColor : shadedSingleColor;

	union()
	{
		difference()
		{
		      base( frontColor,sideColor );

			if (show_front) {
				frontSpeaker(frontSpeakerColor);
				frontButton(frontButtonColor);
			}

			//cutout room for flush items to avoid overlapping surfaces
			if (show_flush) {
				proximity(safety,  proximityColor);
				backCamera(safety, backCameraColor);
				flash(safety, flashColor);
				frontCamera(safety, frontCameraColor);
				screen(safety, screenColor);
			}

			if (show_misc_side) {
				micSpeaker(bottomMicSpeakerColor);
				sim(safety, simColor);
				jack(jackColor);
				topMic(topMicColor);
			}

			if (show_connector) {
				connector(connectorColor);
			}

			if (show_buttons) {
				muteSlot(muteSlotColor);
			}
		}

		//reinsert all flush items in the cutouts
		if (show_flush) {
			proximity(0, proximityColor);
			backCamera(0, backCameraColor);
			flash(0, flashColor);
			frontCamera(0, frontCameraColor);
			screen(0, screenColor);
		}

		if (show_buttons) {
			muteButton(muteButtonColor);
			upDown(upDownColor);
			sleepButton(sleepColor);
		}

		if (show_misc_side) {
			sim(0, simColor);
		}
	}
}

module base(mainColor, sideColor) {
	union() {
		//Create glass-part
		color(mainColor) roundedRect([glassHeight, glassWidth, glassDepth], cornerRadius);
		//Create steel-part
		color(sideColor) translate([0, 0, glassThick]) roundedRect([steelHeight, steelWidth, steelDepth], cornerRadius);
	}
}

module frontSpeaker(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-frontSpeakerVerticalCenter), 0 ,glassDepth-frontSpeakerDepth])
				roundedRect([frontSpeakerHeight, frontSpeakerWidth, frontSpeakerDepth+safety], elementCornerRadius);
}

module frontButton(elementColor) {
	color(elementColor) translate([steelHeight/2-(steelHeight-frontButtonVerticalCenter), 0, frontButtonSphereRadius + glassDepth - frontButtonDepth/2])
		sphere(r = frontButtonSphereRadius,$fn=extra_quality);
}

module proximity(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-proximityVerticalCenter), 0 ,glassDepth-flushEmbed])
			roundedRect([proximityHeight, proximityWidth, flushEmbed + space], elementCornerRadius);
}

module backCamera(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-backCameraCenter), (steelWidth/2 - backCameraCenter), -space])
			cylinder(h = flushEmbed+space, r = backCameraRadius, $fn=quality);
}

module flash(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-flashVerticalCenter), (steelWidth/2 - flashHorizontalCenter),-space])
			cylinder(h = flushEmbed+space, r = flashRadius, $fn=quality);
}

module frontCamera(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-frontCameraVerticalCenter), (steelWidth/2 - frontCameraHorizontalCenter), glassDepth - flushEmbed])
			cylinder(h = flushEmbed+space, r = frontCameraRadius, $fn=quality);
}

module screen(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-screenVerticalDistance), (steelWidth/2 - screenHorizontalDistance), glassDepth-flushEmbed])
			cube([screenHeight, screenWidth, flushEmbed+space]);
}

module micSpeaker(elementColor) {
	color(elementColor)
	union() {
		translate([steelHeight/2-bottomMicSpeakerDepth, bottomMicSpeakerLeftHorizontalDistance-steelWidth/2-bottomMicSpeakerWidth/2, glassDepth/2])
			rotate([0,90,0])
				roundedRect([bottomMicSpeakerHeight, bottomMicSpeakerWidth, bottomMicSpeakerDepth + safety], elementCornerRadius);
		translate([steelHeight/2-bottomMicSpeakerDepth, bottomMicSpeakerRightHorizontalDistance-steelWidth/2-bottomMicSpeakerWidth/2, glassDepth/2])
			rotate([0,90,0])
				roundedRect([bottomMicSpeakerHeight, bottomMicSpeakerWidth, bottomMicSpeakerDepth + safety], elementCornerRadius);
	}
}

module sim(space, elementColor) {
	color(elementColor)
		translate([-(steelHeight/2-simVerticalDistance-simWidth/2), steelWidth/2 - flushEmbed, glassDepth/2])
			rotate([-90,0,0])
				roundedRect([simWidth, simHeight,  flushEmbed + space], elementCornerRadius);
}

module jack(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2+safety), (steelWidth/2 - jackHorizontalDistance), glassDepth/2])
			rotate([0,90,0])
				cylinder(h=jackDepth + safety, r= jackRadius, $fn=quality);
}

module topMic(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2+safety), (steelWidth/2 - topMicHorizontalDistance),glassDepth/2])
		rotate([0,90,0])
			cylinder(h=topMicDepth + safety, r = topMicRadius, $fn=quality);
}

module connector(elementColor) {
	color(elementColor)
		translate([steelHeight/2-connectorDepth, 0, glassDepth/2])
		rotate([0,90,0])
			roundedRect([connectorHeight, connectorWidth, connectorDepth + safety], elementCornerRadius);
}

module muteSlot(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2)+muteHeight/2+muteTop,-steelWidth/2+muteDepth,glassDepth/2])
			rotate([90,0,0])
				roundedRect([muteHeight, muteWidth, muteDepth+safety], elementCornerRadius/2);
}

module muteButton(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2)+muteHeight/2+muteTop,-steelWidth/2+muteDepth,glassDepth/2 - muteWidth/4])
			rotate([90,0,0])
				roundedRect([muteHeight, muteWidth/2, muteDepth*2], elementCornerRadius/2);
}

module upDown(elementColor) {
	color(elementColor)
		union() {
			translate([-(steelHeight/2)+upCenter, -steelWidth/2+safety, glassDepth/2])
				rotate([90,0,0])
					cylinder(h=upDownDepth+safety, r = upDownRadius, $fn=quality);
			translate([-(steelHeight/2)+downCenter, -steelWidth/2+safety, glassDepth/2])
				rotate([90,0,0])
					cylinder(h=upDownDepth+safety, r = upDownRadius, $fn=quality);
	}
}

module sleepButton(elementColor) {
	color(elementColor)
		translate([-(steelHeight/2)-sleepDepth,steelWidth/2-sleepHorizontalDistance+sleepWidth/2, glassDepth/2])
			rotate([90,0,90])
				roundedRect([sleepWidth, sleepHeight, sleepDepth+safety], elementCornerRadius*1.3);
}

module roundedRect(size, radius)
{
	x = size[0];
	y = size[1];
	z = size[2];

	linear_extrude(height=z)
	hull()
	{
		// place 4 circles in the corners, with the given radius
		translate([(-x/2)+(radius), (-y/2)+(radius), 0]) circle(r=radius, $fn=quality);
		translate([(x/2)-(radius), (-y/2)+(radius), 0]) circle(r=radius, $fn=quality);
		translate([(-x/2)+(radius), (y/2)-(radius), 0]) circle(r=radius, $fn=quality);
		translate([(x/2)-(radius), (y/2)-(radius), 0]) circle(r=radius, $fn=quality);
	}
}

```


[User]
Okay, so I'm trying to design a parametric gyrothecube, you know, like those interlocking, rotating puzzle things. I've got some ideas down, but I'm having trouble getting the parameters right to make it robust and easily printable.

Here's the gist of it: I want a series of nested cube-like shapes, where each "cube" is actually a sphere cut by a cube, and they're connected by cylindrical joints that allow them to rotate. Each stage rotates relative to the previous, and should also nest inside the other to make a cube when all stages are locked in.

Here's what I'm thinking about the parameters:

*   **`size`**: The overall size of the largest stage of the cube. Think of this as the "width" or "diameter" if it were a regular cube. Everything else will be relative to this.
*   **`thickness`**:  The thickness of the material used for each "cube" face, so to speak. This will be subtracted from the full sphere to give me a hollow shape and a printable part.
*   **`clearance`**: The space between the rotating parts and the non-rotating walls of each stage. This will be key to ensure the parts can move smoothly.
*   **`tension`**: A small amount of "tightness" added to the cylindrical connection between two parts, to ensure they don't wobble too much. This could even be a negative number if it was useful for printability, though we shouldn't require it.
*   **`stages`**: The number of nested, rotating "cube" stages.
*   **`angle`**:  The angle used to generate the faces of each cube. A value of 52 is pretty good as it gives something that visually appears to be cube-like from a distance.

For each stage, I want:

1.  A sphere, cut by a cube, to create each stage's shell. The cut cube's size should decrease by about two times the thickness + clearance for each layer.
2.  Cylindrical connectors connecting the sphere cut to the shell of the next layer. The connectors should sit on the edges of the cut cube. This is the part that makes it rotate.
3.  The cylindrical connections of each stage should fit smoothly into the space allocated on the next stage.
4.  The rotations should be controlled by a parameter that is some function of $t, for animation purposes. The rotation angles should all start at 0 when $t is zero. This function should vary for each nested stage. A good starting point would be something like 180 * k * $t, where k is an integer that's different on each nested stage. It would be good if some stages could go in the opposite direction to others, too. For the purposes of the rotation, assume that each stage is always rotated relative to the stage that it nests into. The rotation axes should be on the horizontal planes, alternating from the x and y axis, and each stage should also be rotated around the z axis by 45 degrees.

I want the final OpenSCAD file to be fully parametric, so I can easily change these values and generate different sized and nested cubes. I don't need any fancy user interfaces or anything, just a working scad file. I am familiar with using the `rotate`, `translate`, `union`, `intersection`, `difference`, and `cylinder` primitives in OpenSCAD.

Can you generate that for me?

[Assistant]
parametric_gyrothecube.scad:
```
size = 100;
thickness = 2;
clearance = 3;
tension = 0.5;
stages = 5;
angle = 52;
$fs = 1;
$fa = 5;

//%cube(size, center = true);

*rotate(0) {
	stage(100, 0);
	rotate([180 * 5 * $t, 0, 45]) rotate(45) {
		stage(90, 1);
		rotate([180 * -7 * $t, 0, 45]) rotate(45) {
			stage(80, 2);
			rotate([180 * -9 * $t, 0, 45]) rotate(45) {
				stage(70, 3);
				rotate([180 * 11 * $t, 0, 45]) rotate(45) {
					stage(60, 4);
				}
			}
		}
	}
}

for(stage = [0: stages - 1]) rotate(stage * 0) translate([0, 0, -(thickness + clearance) * stage]) stage(size + thickness * 2 - (thickness + clearance) * 2 * stage, stage);

module stage(size, stage) difference() {
	union() {
		intersection() {
			sphere(size / sin(angle) / 2);
			cube(size - thickness * 2, center = true);
		}
		if (stage != 0) for(a = [0, 1]) rotate([0, 90, -45 + 180 * a]) translate([0, 0, (size / sin(angle) / 2 - thickness)]) cylinder(r1 = clearance + thickness, r2 = 0, h = clearance + thickness);
	}
	difference() {
		sphere(size / sin(angle) / 2 - thickness);
		if (stage != stages - 1) for(a = [0, 1]) rotate([0, 90, 45 + 180 * a]) translate([0, 0, -(size / sin(angle) / 2 - thickness)]) difference() {
			cylinder(r1 = clearance, r2 = 0, h = clearance);
			translate([0, 0, clearance - thickness + tension]) cylinder(r1 = 0, r2 = clearance, h = clearance);
		}
	}
	for(o = [0:2]) rotate([0, 90 + 90 * o, 90 + 45 * o]) cylinder(r = sqrt(abs(pow(size / sin(angle), 2) - pow(size, 2))) / 2, h = size * 2, center = true);
}

```


[User]
Okay, I've been experimenting with this twisted rod design in OpenSCAD, and I'm hoping you can help me make it more flexible and parametric.

Basically, I have a rod segment created by twisting a circle as it's extruded, creating a kind of spiral effect. I've also incorporated a version where there are counter-spirals, creating more of a cross-weave look. I've further combined these twisted rod segments, adding a rounded cap on one end, and screw threads on the other, so the segments can be combined to make a longer wand.

Here's what I'd like to be able to control:

**Core Rod Segment:**
*   **`h` (Height):** The height of a single rod segment.
*   **`cr` (Circle Radius):** The radius of the circle that's being extruded and twisted to form the rod segment.
*   **`w` (Wiggle Distance):** The distance the circle is offset during the extrusion (this creates the wavy spiral).
*   **`nw` (Number of Wiggles):** The number of full twists (360 degree rotations) per rod segment. This directly controls the density of the spiral.
*   **`c` (Spiral Type):** An integer variable to control the spiral style:
    *   `0`: Single spiral direction.
    *   `1`: Counter-spirals forming a cross pattern.
    *   `2`: Double the counter-spiral pattern with a 180 degree phase rotation, causing each counter-spiral to mirror the other.

**Screw Threads (Inner and Outer):**
*   **`ih` (Inner Height):** The height of the threaded screw/hole.
*   **`iw` (Inner Wiggles):** The number of full twists (360 degree rotations) in the screw thread.
*   **`gap`:** A small gap added to the outer screw threads to ensure a proper fit.

**Other Parameters:**
*   **`g`:** A tiny offset used to prevent faces from aligning perfectly and causing OpenSCAD rendering issues.
*   **`spacing`:** Spacing between rod segments when displayed horizontally (for printing all the parts).
*   **`vspacing`:** The vertical spacing of the stacked rod segments when displaying the assembled wand vertically.

**Modules:**
I've also defined these basic modules, but it would be great if the parametric version keeps these:
*   `core()`: Generates the core rod segment based on the given parameters.
*   `top()`: Creates the top rod segment with a sphere cap and a screw hole on the bottom.
*   `mid()`: Creates a middle rod segment with a screw on top and a screw hole on the bottom.
*   `bottom()`: Creates the bottom rod segment with a screw on top and a flat bottom.
*   `inner()`: Generates the male screw thread.
*   `outer()`: Generates the female screw hole.
*   `plated()`: Arranges a set of `bottom`, `mid`, and `top` segments horizontally for printing.
*   `stacked()`: Arranges `top`, `mid`, and `bottom` vertically to show how the assembled wand will look.

**Specific Request:**

I would like you to generate a parametric OpenSCAD file that maintains this basic functionality and design logic but allows these parameters to be easily adjusted.  The goal is to be able to quickly change the height, radius, spiral density, screw thread size, and gaps, and see the design update automatically, both in the `plated` and `stacked` views.  Ideally, all parameters can be set with a single set of variable declarations. It should also have a modular structure, similar to my current code. I do not need external libraries other than what is included with OpenSCAD's standard installation.

[Assistant]
thing2.scad:
```
// threaded rod
//
// rod is threaded both on the inside and the outside.

h=100;		// height of each segment
cr=20;		// radius of the circle that forms the rod
w=10;		// distance of 'wiggle' in rod
nw=2;		// number of wiggles per rod segment
c = 2;		// 1 = counter-spirals, forming cross shapes, 0=spirals

// the core of each rod segment

module core() {
	linear_extrude(height = h, center = false, convexity = 10, twist = nw*360)
		translate([w, 0, 0]) circle(r = cr);
	if (c > 0) {
		linear_extrude(height = h, center = false, convexity = 10, twist = -nw*360) translate([w, 0, 0]) circle(r = cr);
		}
	if (c==2) {
		rotate([0,0,180]) {
			linear_extrude(height = h, center = false, convexity = 10, twist = nw*360)
				translate([w, 0, 0]) circle(r = cr);
			linear_extrude(height = h, center = false, convexity = 10, twist = -nw*360)
				translate([w, 0, 0]) circle(r = cr);
			}
		}
	}

// the top rod segment, which has a sphere at the top, and
// a screw hole in the bottom

module top() {
	difference() {
		union() {
			core();
			translate([0,0,h]) sphere(r=cr+w); // cap top
			}
		translate([0,0,-g]) outer(); // screw hole in other end
		}
	}

// middle rod segments have screws on top, and holes on the bottom

module mid() {
	difference() {
		union() {
			core();
			translate([0,0,h-g]) inner(); // screw on top end
			}
		translate([0,0,-g]) rotate([0,0,180]) outer(); // screw hole in bottom end
		}
	}

// the bottom rod segment has a screw on top, and flat bottom.

module bottom() {
	core();
	translate([0,0,h-g]) inner(); // screw in top end
	}

ih = 20;	// height of the inner threaded screw
iw=5;		// number of 'wiggles' in the height of the screw

// draw the screw shape. Note the conical top, allowing it to
// fill holes that canprint without support (I hope). And it
// should make it easier to put the screws into the holes.

module inner() {
	intersection() {
		linear_extrude(height=ih, center=false, convexity=10, twist=iw*360)
			translate([1,0,0]) circle(r=ih/2);
		cylinder(r1=ih, r2=0, h=ih);
		}
	}

gap = 0.1;	// gap between screw and hole. If it's too tight, increase it.

// Shape of the hole into which the screw screws. It's identical
// to the inner shape, plus the gap added to the radius and height.

module outer() {
	intersection() {
		linear_extrude(height=ih, center=false, convexity=10, twist=iw*360)
			translate([1,0,0]) circle(r=ih/2+gap);
		cylinder(r1=ih+gap, r2=0, h=ih);
		}
	}

g=0.05;		//tiny number, added to keep faces from aligning
				//precisely, which upsets OpenSCAD when it happens.
spacing=60;	//spacing between plated rod segments.

// draw the rods next to each other for printing on a single plate.
// For TOM, it might be better to pack them more tightly, or the
// rod will be rather small.

module plated() {
	translate([-2*spacing,0,0]) bottom();
	translate([-spacing,0,0]) mid();
	mid();
	translate([spacing,0,0]) mid();
	translate([2*spacing,0,0]) top();
	}

vspacing = h+gap+ih+10;	// vertical spacing

// Draw the rod segments stacked vertically, so you can see how
// it will look assembled.

module stacked() {	// view lined up for perspective
	translate([0,0,vspacing]) top();
	//translate([0,0,3*vspacing]) mid();
	//translate([0,0,vspacing]) mid();
	//translate([0,0,vspacing]) mid();
	bottom();
	}

//plated();
stacked();
```


[User]
Okay, I'm looking for a parametric miter box design in OpenSCAD, specifically for cutting t-slot extrusions. I want to be able to easily adjust the dimensions and angles.

I've started something myself, but it's not parametric and I don't think I'm doing the boolean operations in the best way. Here's the basic idea:

I want a box-like structure, essentially a rectangular prism with some cuts in it. The basic box should have adjustable dimensions for length (x), width (y), and height (z).  These define the overall size of the box and also the size of the material we'll be using as a guide.

Then, I need to cut out guides for the saw, that create angled cuts. I need the following angles: 90 degrees (straight cut), 45 degrees, and 30 degrees (plus the negative versions of those angles).  I think I was getting them okay, but it was messy. The saw kerf I'm imagining is about 2mm or so, that should be adjustable, too. Also, I want the cut guides to extend well past the box, so there's plenty of guide for the blade. I think a parameter to control their extended length would also be useful.  Finally, the height of the cut guides should at least be as tall as the 'z' height of the box.

It would also be great if the design had a tolerance built into the cuts so the t-slot extrusion doesn't bind or get scratched up by the guide. It should be a small tolerance of maybe .2 or .3 mm on each side.

To clarify the basic dimensions, the main body will be a simple rectangular prism, and the cuts will essentially be thin rectangles cut through it at the required angles. I imagine they will be similar to a miter saw guide, but they should have a "slot" shape so the saw blade can pass.

So, to summarize, here are the parameters I'm looking for:

*   `x`: Length of the miter box.
*   `y`: Width of the miter box (where the t-slot sits).
*   `z`: Height of the miter box.
*   `kerf`: Width of the saw cut.
*   `cut_length_extension`: Length the cut guide extends past the main box.
*   `tolerance`: tolerance applied to the cuts to allow free movement of the t-slot.
*  `cut_height`: the height of the cut guides.

Please design this using OpenSCAD so I can easily generate the 3D model. I'm hoping to avoid using any modules that require a 3rd party installation. I'm thinking using standard boolean operations would be best.

[Assistant]
miter.scad:
```
x=100;
y=30;
z=30;
cut=2;
module miter(){
difference(){
cube([x,y+10,z+10],true);
union(){
translate([0,0,5])cube([x+12,y+1.5,z+10],true);
translate([0,0,5])cube([cut,y*2,z+10],true); //90
rotate([0,0,45])translate([0,0,5])cube([cut,y*3,z+10],true); //45
rotate([0,0,-45])translate([0,0,5])cube([cut,y*3,z+10],true); //-45
rotate([0,0,60])translate([0,0,5])cube([cut,y*3,z+10],true); //60
rotate([0,0,-60])translate([0,0,5])cube([cut,y*3,z+10],true); //-60
}
}
}

miter();
```


[User]
Okay, I'm looking to create a custom encoder wheel for a robotics project, and I need it to be parametric so I can easily adjust the dimensions. I've seen some examples, but they don't quite cover everything I need. Here's what I'm hoping to achieve:

**Core Functionality:**

*   **Wheel Diameter/Circumference:** I need to be able to specify the wheel's circumference, and the script should calculate the diameter based on that. I plan to measure the circumference at the wheel's surface, so tire thickness won't matter.
*   **Internal Width:** The wheel needs a specified internal width, like the tire width, and there should be a small amount of play added to the width to make sure it can easily move on the axle.
*   **Mounting Hole:** The wheel will mount on a bearing, so the script needs to accept the mounting hole diameter, as well as an amount of play, and make an appropriate hole. I'll mostly be using 608 bearings, but will also be using other bearings as well, so that should be parametrically adjustable. I'd also like to be able to use constraints on the inside of the wheel to partially block the mounting hole for specific mounting solutions.
*   **Shoulders/Encoder:** The wheel should have shoulders extending outward on both sides. I need to be able to adjust the height and thickness of these shoulders.
*   **Timing Holes:** The encoder needs to have timing holes around the circumference of the shoulder. I need to be able to specify the number of these holes, and how far they are inset from the outer edge of the shoulder.
*   **Captive Nuts:**  I also want the option to include captive nut traps in the wheel, so that I can secure it to a shaft or bearing with set screws or bolts. I need to control the number of these traps, their diameter, and their thickness, as well as the diameter of the clearance hole for set screws.
*   **Alignment/Pin System:**  I need to be able to optionally add pins to the wheel that will align and/or snap it to a cap that will fit over the wheel. I should be able to define the number of pins, their length, and their diameter. I should also be able to optionally replace the pins with bolt-through holes if I want to use fasteners instead of pins. The diameter of these bolt holes should be customizable.

**Cap Functionality:**

*   **Cap Diameter:** The script needs to generate a cap that fits over the shoulders of the wheel. The default should be the outer diameter of the shoulders, but I want to make sure I can override that.
*   **Cap Thickness:** The cap should have a specified thickness, preferably one that matches the shoulder width by default.
*   **Cap Standoff:** The cap should have the option to add a standoff surface inside of the cap around the mounting hole to make a more secure or precise mount with the bearing.
*   **Cap Alignment/Pin System:** The cap should also include corresponding holes for the pins (or pins if I use bolt holes), that align with those in the wheel. The holes on the cap need to be rotated to avoid the nut traps on the wheel (in cases where they are present). The same controls for pin count, length, and diameter and bolting holes should exist as in the wheel, but apply to the cap. Finally, the same constraint inset/thickness control should exist in the cap to allow for partial obstruction of the hole.

**Output:**

*   **Side-by-Side Rendering:** I would like the encoder wheel and the cap to be rendered side by side in the same OpenSCAD output.
*   **Math Output:** It would be useful if the script printed some calculations to the console, such as the circumference of the timing holes, as well as the distance between timing holes for different tire thicknesses.

**Specific Parameters I'd Like to Control:**

*   `bearingSize` (an array of [inner diameter, outer diameter, thickness])
*   `encoderCircumference`
*   `internalWidth`
*   `collarPlay`
*  `collarHeight`
*   `collarWidth`
*   `holeDiameter`
*   `holePlay`
*   `timingHoles`
*   `timingHoleInset`
*   `nutCount`
*   `nutDiameter`
*   `nutThickness`
*   `setScrewDiameter`
*   `constraintInset`
*   `constraintThickness`
*   `capConstraintInset`
*   `capConstraintThickness`
*   `pinCount`
*   `pinLength`
*   `pinDiameter`
*   `useHolesInstead`
*   `mateHoleDiameter`
*   `capDiameter`
*   `capWidth`
*   `capStandoff`
*   `capStandoffWidth`
*  `capHoleRotation`
*   `distanceApart` (distance between wheel and cap rendering)

**Libraries:**

I know that the design is intended to work with the `bearing.scad` file from the MCAD library, so that can be used.

Can you create an OpenSCAD file that includes all of these features?

[Assistant]
ParametricEncoderWheelv0.9.scad:
```
/*
 * Parametric Encoder Wheel, v0.9
 *
 * by Alex Franke (CodeCreations), Mar 2012 - Apr 2012
 * http://www.theFrankes.com
 *
 * Licenced under Creative Commons Attribution - Non-Commercial - Share Alike 3.0
 *
 * INSTRUCTIONS: Choose some values in the "User-defined values" section, and render.
 *
 * The bearing.scad file from the MCAD library has a number of different bearing sizes
 * in it if you're not using a 608.
 *
 * VERSION HISTORY:
 *
 * v0.9, Apr 2, 2012: Added support for bearing constraints, captive nuts, bolting holes,
 * 		and pins for joining the wheel and cap. Both parts are now rendered side by side.
 * 		Added a bunch of new parameters, and some more math output for users.
 *
 * v0.0, Mar 31, 2012: Initial Release.
 */

/////////////////////////////////////////////////////////////////////////////
// User-defined values...
/////////////////////////////////////////////////////////////////////////////
bearingSize = [8, 22, 7]; 		 	// The dimensions of the bearing, if you're using that to define the hole
encoderCircumference = 100;		 	// The circumference at the *surface* of the wheel (subtract tire thickness, e.g.)
internalWidth = bearingSize[2];	 	// The internal width (e.g. tire width) of the wheel. This is the width of a pinch 608 by default
collarPlay = 0.5; 				 	// The amount of play to build into the internal width.
collarHeight = 6; 				 	// How high the shoulders/encoder extend out from the wheel
collarWidth = 1.5; 				 	// How thick the shoulders are
holeDiameter = bearingSize[1]; 	 	// The diameter of the mounting hole. This is the diameter of a 608 bearing by default.
holePlay = 0.5; 					 	// The amount of play built into the mounting hole.
timingHoles = 40;					 	// The number of timing holes to render. (e.g. 100mm circumference / 5mm per hole = 20 holes)
timingHoleInset = 1; 				 	// How far the timing holes are inset from the edge of the shoulder

// Calculated values -- don't change them.
encoderDiameter = encoderCircumference / PI;

// Captive Nut traps allow you to tighten the wheel onto a shaft or bearing.
nutCount = 3;
nutDiameter = 5.4; 				 	// The distance across the nut, from flat to flat, default M3
nutThickness = 2.3; 				 	// The thickness of the nut, default M3
setScrewDiameter = 3;			 	 	// The diameter of the set screw clearance hole, default M3

// The constraint values can be used to add material to the bottom of the mounting hole that partially
// blocks the hole. This can be useful, for example, if you want to constrain a bearing in the hole.
constraintInset = 1.5; 			 	// How far the constraint estends toward the center of the mounting hole
constraintThickness = collarWidth;	 	// The thickness of the contstraining wall
capConstraintInset = 1.5; 			// How far the constraint estends toward the center of the mounting hole on the cap
capConstraintThickness = collarWidth;	// The thickness of the contstraining wall on the cap

// Pins or holes allow the cap to be snapped, glued, or bolted to the encoder wheel.
pinCount = 3; 					 	// The total number of pins / pin holes to render evenly-spaced
pinLength = internalWidth / 2;	 	// The length of the pins/holes
pinDiameter = ((encoderDiameter
	-holeDiameter)/2) * 0.6;		 	// The diameter of the pins/holes
useHolesInstead = false; 				// If true, render bolt through-holes rather than pins and pin holes
mateHoleDiameter = setScrewDiameter; 	// Bolt holes are sized to match hardware, not physical properties.

// These values define the cap
capDiameter = encoderDiameter
	+ (collarHeight*2);			 	// The diameter of the shoulder cap, defaulting to the outer diameter of the encoder
capWidth = collarWidth; 			 	// The thickness of the shoulder cap, defaulting to the thickness of the slotted encoder shoulder
capStandoff = 0;				 	 	// A surface rendered on the inside of the cap around the mounting hole
capStandoffWidth = 1;				 	// The width of the stand-off surface
capHoleRotation = 360/(pinCount*2); 	// Rotation of cap holes (in order to avoid the nut traps)

// Other misc
distanceApart = 10;				 	// How far apart the object will be rendered.

/////////////////////////////////////////////////////////////////////////////
// Don't change the code below unless you know what your'e doing...
/////////////////////////////////////////////////////////////////////////////

// Do some math for the user...
echo ( str("Circumference is ", encoderCircumference, "mm, with ", timingHoles, " timing holes." ) );
echo ( str("Each timing mark is ", encoderCircumference/timingHoles, "mm." ) );
echo ( str("...or ", (encoderCircumference/timingHoles) / 25.4, "in." ) );

echo ( str("For various product + tire thicknesses, where center of product is at this height: " ) );
echo ( str("  1.0mm: ", dist(1), "mm" ) );
echo ( str("  1.5mm: ", dist(1.5), "mm" ) );
echo ( str("  2.0mm: ", dist(2), "mm" ) );
echo ( str("  2.5mm: ", dist(2.5), "mm" ) );
echo ( str("  3.0mm: ", dist(3), "mm" ) );
echo ( str("  3.5mm: ", dist(3.5), "mm" ) );
echo ( str("  4.0mm: ", dist(4), "mm" ) );
echo ( str("  4.5mm: ", dist(4.5), "mm" ) );
echo ( str("  5.0mm: ", dist(5), "mm" ) );

// Render the encoder wheel
translate([0,-(encoderDiameter/2)-collarHeight-(distanceApart/2),0]) {
	renderEncoder();
}

// Render the cap
translate([0,(capDiameter/2)+(distanceApart/2),0]) {
	renderCap();
}

/////////////////////////////////////////////////////////////////////////////
// These are just a couple of helpers / shortcuts
/////////////////////////////////////////////////////////////////////////////

function dist(h) = ( (encoderDiameter+(2*h)) * PI ) / timingHoles;

// Shortcuts that include all the parameters
module renderCap() {
	cap( capDiameter,
		capWidth,
		encoderDiameter,
		holeDiameter + holePlay,
		capStandoff,
		capStandoffWidth,
		pinCount,
		pinLength,
		pinDiameter,
		useHolesInstead,
		mateHoleDiameter,
		capConstraintInset,
		capConstraintThickness
		);
}
module renderEncoder() {
	encoder(  encoderCircumference,
		internalWidth + collarPlay,
		holeDiameter + holePlay,
		collarHeight,
		collarWidth,
		timingHoles,
		timingHoleInset,
		constraintInset,
		constraintThickness,
		pinCount,
		pinLength,
		pinDiameter,
		useHolesInstead,
		mateHoleDiameter,
		capHoleRotation,
		nutCount,
		nutDiameter,
		nutThickness,
		setScrewDiameter
		);
}

/////////////////////////////////////////////////////////////////////////////
// These modules were designed to be a bit more generic. They don't rely on
// any of the variables above.
/////////////////////////////////////////////////////////////////////////////

module encoder( circumference, internalWidth, holeDiameter=8, collarHeight=5, collarWidth=1.5,
	timingHoles=8, timingHoleInset=1, constraintInset=0, constraintThickness=0,
	pinCount=0, pinLength=0, pinDiameter=0, useHolesInstead=false, mateHoleDiameter=0, pinHoleRotation=0,
	nutCount=3, nutDiameter=5.4, nutThickness=2.3, setScrewDiameter=3 ) {

	encoderDiameter = circumference / PI;
	newR = ((encoderDiameter-holeDiameter)/4 - 2)/2.7;
	wallThickness = (encoderDiameter-holeDiameter)/2;
	wallCenterRadius = holeDiameter/2+(wallThickness/2);

	union() {
		difference () {

			// The body of the wheel/shoulder
			union() {
				cylinder( r=encoderDiameter/2 + collarHeight, h=collarWidth );
				translate([0,0,collarWidth])
					cylinder( r=encoderDiameter/2, h=internalWidth);
			}

			// Punch out the mounting hole
			translate([0,0,-0.5])
				cylinder( r=holeDiameter/2, h=internalWidth + collarWidth + 1);

			// Punch out timing holes
			translate([0,0,-0.5]) {
				for ( i = [0 : timingHoles-1] ) {
				   	 rotate( i*(360/timingHoles), [0, 0, 1])
				   	 arc( collarHeight-timingHoleInset,
						collarWidth+1,
						(encoderDiameter/2)+collarHeight-timingHoleInset,
						degrees =180/timingHoles
				    	);
				}
			}

			// Punch out bolting holes if necessary
			if ( pinCount>0 ) {
				rotate([0,0,pinHoleRotation]) {
					if( useHolesInstead ) {
						translate([0,0,-0.5]) {
							pins( pinCount, mateHoleDiameter, internalWidth + collarWidth + 1, wallCenterRadius );
						}
					}
					else {
						translate([0,0,internalWidth + collarWidth + collarPlay - pinLength - 0.5]) {
							pins( pinCount, pinDiameter, pinLength + 0.5, wallCenterRadius );
						}
					}
				}
			}

			// Punch out the nut traps if necessary
			if ( nutCount > 0 ) {
				for ( i = [0 : nutCount-1] ) {
					rotate( i*(360/nutCount), [0, 0, 1]) {
						translate([wallCenterRadius,0,collarWidth+(internalWidth/2)]) {
							rotate([0,-90,180]) {
								nutTrap(
									nutDiameter,
									nutThickness,
									setScrewDiameter,
									depth=(internalWidth/2)+0.5, //0.5 extra so it renders well
									holeLengthTop=wallThickness/2,
									holeLengthBottom=wallThickness/2
								);
							}
						}
					}
				}
			}

			/*
			// Experimental...
			// Holes in idler to conserve filament
			for ( i = [0 : 4] ) {
			   	 rotate( i * 360/5, [0, 0, 1])
			   	 translate([holeDiameter/2 + (encoderDiameter-holeDiameter)/4, 0, -0.5])
			   	 cylinder(h=internalWidth+(2*collarWidth)+1, r=(encoderDiameter-holeDiameter)/4 - 1);
			}

			// Smaller holes in idler to conserve filament
		   	rotate( 360/5/2, [0, 0, 1])
			for ( i = [0 : 4] ) {
			   	 rotate( i*(360/5), [0, 0, 1])
			   	 translate([encoderDiameter/2-newR -1.5, 0, -0.5])
			   	 cylinder(h=internalWidth+(2*collarWidth)+1, r=newR, $fn=10);
			}
			*/
		}

		// Render the constraint surface if necessary
		if ( ( constraintInset > 0 ) && ( constraintThickness > 0 ) ) {
			difference() {
				cylinder( r=holeDiameter/2, h=constraintThickness);
				translate([0,0,-0.5])
					cylinder( r=(holeDiameter/2)-constraintInset, h=constraintThickness+1);
			}
		}
	}
}

module cap( diameter, thickness, hubDiameter, holeDiameter, standoffHeight=0, standoffWidth=0, numPins=0,
	pinHeight=0, pinDiameter=0, useHolesInstead=false, mateHoleDiameter=0, constraintInset=0, constraintThickness=0 ) {

	wallThickness = (hubDiameter-holeDiameter)/2;
	wallCenterRadius = holeDiameter/2+(wallThickness/2);

	render()
	union() {
		difference() {
			// cap body
			union() {
				cylinder( r=diameter/2, h=thickness );
				cylinder( r=(holeDiameter/2)+standoffWidth, h=collarWidth+standoffHeight );
			}

			// Poke out the mounting hole
			translate([0,0,-0.5])
				cylinder( r=holeDiameter/2, h=collarWidth+standoffHeight+1 );

			// Poke out the bolting holes if necessary
			if ( useHolesInstead ) {
				translate([0,0,-0.5]) {
					pins( numPins, mateHoleDiameter, thickness+1, wallCenterRadius );
				}
			}
		}

		// Add the pins, if necessary
		if ( ( !useHolesInstead ) && ( numPins > 0 ) && ( pinHeight > 0 ) && ( pinDiameter > 0 ) ) {
			translate([0,0,thickness]) {
				pins( numPins, pinDiameter, pinHeight, wallCenterRadius );
			}
		}

		// Render the constraint surface if necessary
		if ( ( constraintInset > 0 ) && ( constraintThickness > 0 ) ) {
			difference() {
				cylinder( r=holeDiameter/2, h=constraintThickness);
				translate([0,0,-0.5])
					cylinder( r=(holeDiameter/2)-constraintInset, h=constraintThickness+1);
			}
		}
	}
}

module pins( numPins=3, pinDiameter=3, pinHeight=10, distanceFromCenter=10) {
	for ( i = [1 : numPins] ) {
		rotate( i*(360/numPins), [0, 0, 1]) {
			translate([distanceFromCenter,0,0]) {
				cylinder( r=pinDiameter/2, h=pinHeight, $fn=15);
			}
		}
	}
}

module nutTrap( inDiameter=5.4, thickness=2.3, setScrewHoleDiameter=3, depth=10, holeLengthTop=5, holeLengthBottom=5 )
{
	side = inDiameter * tan( 180/6 );

	render()
	union() {
		for ( i = [0 : 2] ) {
			rotate( i*120, [0, 0, 1])
				cube( [side, inDiameter, thickness], center=true );
		}

		translate([depth/2,0,0])
			cube( [depth, inDiameter, thickness], center=true );

		translate([0,0,-(thickness/2)-holeLengthBottom])
			cylinder(r=setScrewHoleDiameter/2, h=thickness+holeLengthTop+holeLengthBottom, $fn=15);
	}
}

// Why is this not easy in openSCAD? :/
module arc( height, depth, radius, degrees ) {
	// This dies a horible death if it's not rendered here
	// -- sucks up all memory and spins out of control
	render() {
		difference() {
			// Outer ring
			rotate_extrude($fn = 100)
				translate([radius - height, 0, 0])
					square([height,depth]);

			// Cut half off
			translate([0,-(radius+1),-.5])
				cube ([radius+1,(radius+1)*2,depth+1]);

			// Cover the other half as necessary
			rotate([0,0,180-degrees])
			translate([0,-(radius+1),-.5])
				cube ([radius+1,(radius+1)*2,depth+1]);

		}
	}
}

```