[User]
Okay, I'm looking to create a parametric planetary gear bearing that will fit inside a standard 1kg plastic spool, specifically the type used by Makerbot and Ultimachine. These spools have an internal diameter of about 52mm, but I'd like to make it easily adjustable for other spool sizes too. I also want a printable spindle, and I will use the code from the provided scad files, so it needs to be compatible.

Here's what I'm thinking:

**Overall Design:**
*   I need a planetary gear system. The main ring gear will be fixed inside the spool.
*   The planetary gears will rotate around the ring gear.
*   The sun gear will be driven by the printable spindle.
*   The whole assembly should be robust enough to support a reasonable amount of weight, keeping the spool rotating smoothly when filament is pulled from the roll.

**Specific Parameters I need to control:**
*   **`D` (Outer Diameter):** The outer diameter of the main ring gear (which will be the approximate inner diameter of the spool) with some clearance. Defaults to 51.7. This needs to be easily changed as mentioned.
*   **`fD` (Flange Diameter):** The diameter of the flange on the main ring. Defaults to 71.7. This can probably be scaled with `D`.
*   **`T` (Thickness):** The overall thickness of the ring gear. Defaults to 20.
*   **`fT` (Flange Thickness):** The thickness of the flange. Defaults to 5.
*   **`tol` (Clearance):** A small tolerance value for the gear teeth. Defaults to 0.2.
*   **`number_of_planets`:** The number of planetary gears. Defaults to 6.
*   **`number_of_teeth_on_planets`:** The number of teeth on each planetary gear. Defaults to 5.
*   **`approximate_number_of_teeth_on_sun`:** The approximate number of teeth on the sun gear. Defaults to 10.
*   **`P` (Pressure Angle):** The pressure angle of the gear teeth. Defaults to 45.
*   **`nTwist`:** The number of teeth to twist across. Defaults to 1.
*   **`w`:** Width of the hole for the spindle. Defaults to 11.
*    **`DR`:** Maximum depth ratio of teeth. Defaults to 0.5.
*   The outer ring should have a flange for support, as given in the code.
*   I would like to incorporate a monogram as per the code provided.
*   I would like to reuse code modules like `herringbone`, `rack`, `monogram`, `gear`, `flat_extrude`, `gear2D`, `halftooth`, `involute`, and `involute_intersect_angle`, and would like the code to be as close to the provided one as reasonably possible.
* The `monogram` should be rotated as in the example code, for printing purposes.

**Requirements for the OpenSCAD File:**
*   It should be fully parametric, with all the above parameters easily adjustable at the beginning of the file.
*   It should generate the ring gear, planetary gears, and the sun gear.
* The sun gear should have a hole for the spindle.
* The code should take into account the helix of the gear and that it is a herringbone.
*   The code should echo intermediate values as in the provided code such as ns, pitch, and helix_angle, for debugging.
*   The code should be well-commented, explaining what each section does and how the parameters affect the design.

Essentially, I'm looking for a way to easily create a planetary gear system within a spool, and to make this as parametric as possible. I'm not looking for a spindle in this model, as I will be using tjhowse's printable one. Could you create an OpenSCAD file that meets these requirements? I have included my current code for reference as bearing.scad above.

[Assistant]
bearing.scad:
```
// Planetary gear bearing (customizable)

// outer diameter of ring
D=51.7;
// outer diameter of flange
fD=71.7;
// thickness
T=20;
// flange thickness
fT=5;
// clearance
tol=0.2;
number_of_planets=6;
number_of_teeth_on_planets=5;
approximate_number_of_teeth_on_sun=10;
// pressure angle
P=45;//[30:60]
// number of teeth to twist across
nTwist=1;
// width of hole
w=11;

DR=0.5*1;// maximum depth ratio of teeth

m=round(number_of_planets);
np=round(number_of_teeth_on_planets);
ns1=approximate_number_of_teeth_on_sun;
k1=round(2/m*(ns1+np));
k= k1*m%2!=0 ? k1+1 : k1;
ns=k*m/2-np;
echo(ns);
nr=ns+2*np;
pitchD=0.9*D/(1+min(PI/(2*nr*tan(P)),PI*DR/nr));
pitch=pitchD*PI/nr;
echo(pitch);
helix_angle=atan(2*nTwist*pitch/T);
echo(helix_angle);

phi=$t*360/m;

module outside(){
	union(){
		cylinder(r=D/2,h=T,center=true,$fn=100);
		translate(v=[0,0,-1*T/2]){cylinder(r=fD/2,h=fT,center=false,$fn=100);}
	}
}

translate([0,0,T/2]){
	difference(){
		outside();
		herringbone(nr,pitch,P,DR,-tol,helix_angle,T+0.2);
		difference(){
			translate([0,-D/2,0])rotate([90,0,0])monogram(h=10);
			cylinder(r=D/2-0.25,h=T+2,center=true,$fn=100);
		}
	}
	rotate([0,0,(np+1)*180/ns+phi*(ns+np)*2/ns])
	difference(){
		mirror([0,1,0])
			herringbone(ns,pitch,P,DR,tol,helix_angle,T);
		cylinder(r=w/2,h=T+1,center=true,$fn=50);
	}
	for(i=[1:m])rotate([0,0,i*360/m+phi])translate([pitchD/2*(ns+np)/nr,0,0])
		rotate([0,0,i*ns/m*360/np-phi*(ns+np)/np-phi])
			herringbone(np,pitch,P,DR,tol,helix_angle,T);
}

module rack(
	number_of_teeth=15,
	circular_pitch=10,
	pressure_angle=28,
	helix_angle=0,
	clearance=0,
	gear_thickness=5,
	flat=false){
addendum=circular_pitch/(4*tan(pressure_angle));

flat_extrude(h=gear_thickness,flat=flat)translate([0,-clearance*cos(pressure_angle)/2])
	union(){
		translate([0,-0.5-addendum])square([number_of_teeth*circular_pitch,1],center=true);
		for(i=[1:number_of_teeth])
			translate([circular_pitch*(i-number_of_teeth/2-0.5),0])
			polygon(points=[[-circular_pitch/2,-addendum],[circular_pitch/2,-addendum],[0,addendum]]);
	}
}

module monogram(h=1)
linear_extrude(height=h,center=true)
translate(-[3,2.5])union(){
	difference(){
		square([4,5]);
		translate([1,1])square([2,3]);
	}
	square([6,1]);
	translate([0,2])square([2,1]);
}

module herringbone(
	number_of_teeth=15,
	circular_pitch=10,
	pressure_angle=28,
	depth_ratio=1,
	clearance=0,
	helix_angle=0,
	gear_thickness=5){
union(){
	gear(number_of_teeth,
		circular_pitch,
		pressure_angle,
		depth_ratio,
		clearance,
		helix_angle,
		gear_thickness/2);
	mirror([0,0,1])
		gear(number_of_teeth,
			circular_pitch,
			pressure_angle,
			depth_ratio,
			clearance,
			helix_angle,
			gear_thickness/2);
}}

module gear (
	number_of_teeth=15,
	circular_pitch=10,
	pressure_angle=28,
	depth_ratio=1,
	clearance=0,
	helix_angle=0,
	gear_thickness=5,
	flat=false){
pitch_radius = number_of_teeth*circular_pitch/(2*PI);
twist=tan(helix_angle)*gear_thickness/pitch_radius*180/PI;

flat_extrude(h=gear_thickness,twist=twist,flat=flat)
	gear2D (
		number_of_teeth,
		circular_pitch,
		pressure_angle,
		depth_ratio,
		clearance);
}

module flat_extrude(h,twist,flat){
	if(flat==false)
		linear_extrude(height=h,twist=twist,slices=twist/6)child(0);
	else
		child(0);
}

module gear2D (
	number_of_teeth,
	circular_pitch,
	pressure_angle,
	depth_ratio,
	clearance){
pitch_radius = number_of_teeth*circular_pitch/(2*PI);
base_radius = pitch_radius*cos(pressure_angle);
depth=circular_pitch/(2*tan(pressure_angle));
outer_radius = clearance<0 ? pitch_radius+depth/2-clearance : pitch_radius+depth/2;
root_radius1 = pitch_radius-depth/2-clearance/2;
root_radius = (clearance<0 && root_radius1<base_radius) ? base_radius : root_radius1;
backlash_angle = clearance/(pitch_radius*cos(pressure_angle)) * 180 / PI;
half_thick_angle = 90/number_of_teeth - backlash_angle/2;
pitch_point = involute (base_radius, involute_intersect_angle (base_radius, pitch_radius));
pitch_angle = atan2 (pitch_point[1], pitch_point[0]);
min_radius = max (base_radius,root_radius);

intersection(){
	rotate(90/number_of_teeth)
		circle($fn=number_of_teeth*3,r=pitch_radius+depth_ratio*circular_pitch/2-clearance/2);
	union(){
		rotate(90/number_of_teeth)
			circle($fn=number_of_teeth*2,r=max(root_radius,pitch_radius-depth_ratio*circular_pitch/2-clearance/2));
		for (i = [1:number_of_teeth])rotate(i*360/number_of_teeth){
			halftooth (
				pitch_angle,
				base_radius,
				min_radius,
				outer_radius,
				half_thick_angle);
			mirror([0,1])halftooth (
				pitch_angle,
				base_radius,
				min_radius,
				outer_radius,
				half_thick_angle);
		}
	}
}}

module halftooth (
	pitch_angle,
	base_radius,
	min_radius,
	outer_radius,
	half_thick_angle){
index=[0,1,2,3,4,5];
start_angle = max(involute_intersect_angle (base_radius, min_radius)-5,0);
stop_angle = involute_intersect_angle (base_radius, outer_radius);
angle=index*(stop_angle-start_angle)/index[len(index)-1];
p=[[0,0],
	involute(base_radius,angle[0]+start_angle),
	involute(base_radius,angle[1]+start_angle),
	involute(base_radius,angle[2]+start_angle),
	involute(base_radius,angle[3]+start_angle),
	involute(base_radius,angle[4]+start_angle),
	involute(base_radius,angle[5]+start_angle)];

difference(){
	rotate(-pitch_angle-half_thick_angle)polygon(points=p);
	square(2*outer_radius);
}}

// Mathematical Functions
//===============

// Finds the angle of the involute about the base radius at the given distance (radius) from it's center.
//source: http://www.mathhelpforum.com/math-help/geometry/136011-circle-involute-solving-y-any-given-x.html

function involute_intersect_angle (base_radius, radius) = sqrt (pow (radius/base_radius, 2) - 1) * 180 / PI;

// Calculate the involute position for a given base radius and involute angle.

function involute (base_radius, involute_angle) =
[
	base_radius*(cos (involute_angle) + involute_angle*PI/180*sin (involute_angle)),
	base_radius*(sin (involute_angle) - involute_angle*PI/180*cos (involute_angle))
];

```


[User]
Okay, I need an OpenSCAD design for a box with a lid, and I want it to be parametric so I can easily adjust the dimensions and some other features.

Here's what I'm looking for:

*   **Basic Box Shape:** The box should be rectangular with rounded corners. I want to specify the inside width, length, and height.

*   **Wall Thickness:** I need to be able to set the wall thickness of the box.

*   **Corner Radius:** The corner rounding should be adjustable.

*   **Lid:** The box should have a lid that fits snugly. I need parameters for the percentage of the total box height that the lid takes up, as well as for the lip that sticks down into the box. I need both of these as percentages of the total box height.

*   **Fit:** It needs to be easy to adjust how tightly the lid fits into the base of the box. Maybe with settings like "Super fit", "Force fit", "Hold fit", "Slide fit", and "Free fit" or some other way to easily adjust the clearance between the lid and the base.

*   **Optional Gap:** I'd like an optional setting to create a small gap inside the base of the box so the outside of the lid fits flush. This shouldn't change the overall height of the box, but I need to be able to control how big this gap is, if I choose to use it.

*   **Print Layout:** I'd like the generated code to also generate both parts of the box, the base and the lid, for printing. These should be laid out side-by-side (or in some other way that makes sense for printing). I need to be able to control the distance between these parts to ensure they don't print together.

*   **Corner Rounding:** I need an option to only round the sides, and not the top and bottom, of the box if desired.

*   **Libraries:** I'd like you to use the `boxes.scad` file from the MCAD library for the core box generation.

So, essentially, I want a parametric version of the box shown in the `Box.scad` example I found. It is included below for reference, though I do not expect that you need to parse it as part of this prompt. I understand that it uses MCAD, and I would like you to use that as well.

```
// Box with rouned corners, by Clif Cox 04/09/2013
// Uses outside mesurements in function calls

include </home/clif/src/openscad/boxes.scad>;
use <MCAD/boxes.scad>;

// preview[view:south west, tilt:top diagonal]

/* [Main] */

// Inside width
width=12;
// Inside Length
length=12;
// Inside Height
height=12;
// Wall Thickness
wall=1;
// Corner Radius
radius=2;
// Percetage of total height for lid
lidp= 20;
// Percetage of total height for lip
lipp= 5;

// Get outside mesurments
w = width + 2*wall; l = length + 2*wall; h = height + 2*wall; r = (radius > 0 ? radius + wall:0);
// Get actuall lid measurments
lidh=h*lidp/100; liph= h*lipp/100;

/* [Advanced] */

// Only round the sides of the box?
sidesonly=1; // [0:No, 1:Yes]

// How snugly should the parts fit?
fit = 0; // [0:Super fit, 0.2:Force fit, 0.3:Hold fit, 0.4:Slide fit, 0.5:Free fit]

// Should there be a gap inside so the outside lips fit flush? (This does not change the hight of the box)
gap= 0; // [0:No gap, 0.1:Small gap, 0.3:Medium gap, 0.5:Large gap]

// How far to seperate the pices when printing both
seperation = 2;

// Number of segments in a circle
$fn = 50;

/* [Hidden] */

// Fudge Factor
x= 0.1;

// translate([0,0, 5]) boxlip(width, length, height, wall/2, radius, lidh, lidh+liph); // Test lip

boxWithLid(w, l, h, wall, r, sidesonly, 1);
boxWithLid(w, l, h, wall, r, sidesonly, 2);

// Make a hollow box with a lid
module boxWithLid(width, length, height, wall, radius, sidesonly, part) {
	w = 2*wall;
	// This just flips the top upside down to print side by side with the bottom
	translate([(part < 3 ? (part-1.5):0)*(width+seperation), 0, 0]) rotate(a=[(part==1 ? 1:0)*180, 0, 0]) {
		difference() {
    	    		hollowbox(width, length, height, wall, radius, sidesonly=sidesonly);
			if (part == 1) difference() {		// Subtrack bottom of box to make top
				cube([width+x, length+x, height+x], center=true);
				translate([0, 0, (height-lidh+x)/2]) cube([width+x, length+x, lidh+x], center=true);
				boxlip(width+x, length+x, height+x, (wall-fit+x)/2, radius+x, lidh, liph);
			}
			if (part == 2) {			// Subtrack top of box to make bottom
				translate([0, 0, (height-lidh-gap+x)/2]) cube([width+x, length+x, lidh+gap+x], center=true);
				boxlip(width+x, length+x, height+x, (wall+fit+x)/2, radius+x, lidh, liph);
			} 					// Else Make the whole box
		}
	}
}

// Make a hollow box
module hollowbox(width, length, height, wall, radius) {
    w = 2*wall;

	if (radius > 0) difference() {
		roundedBox([width, length, height], radius, sidesonly=sidesonly);
		roundedBox([width-w, length-w, height-w], radius-wall, sidesonly=sidesonly);
	} else difference() {
        cube([width, length, height], center=true);
        cube([width-w, length-w, height-w], center=true);
	}
}

// Make the lip btween the top and bottom
module boxlip(width, length, height, wall, radius, top, thick) {
	w = 2*wall;

	intersection() {
		hollowbox(width, length, height, wall, radius);
		translate([0,0,(height-thick)/2-top]) cube([width+x, length+x, thick], center=true);
	}
}

```

[Assistant]
Box.scad:
```
// Box with rouned corners, by Clif Cox 04/09/2013
// Uses outside mesurements in function calls

include </home/clif/src/openscad/boxes.scad>;
use <MCAD/boxes.scad>;

// preview[view:south west, tilt:top diagonal]

/* [Main] */

// Inside width
width=12;
// Inside Length
length=12;
// Inside Height
height=12;
// Wall Thickness
wall=1;
// Corner Radius
radius=2;
// Percetage of total height for lid
lidp= 20;
// Percetage of total height for lip
lipp= 5;

// Get outside mesurments
w = width + 2*wall; l = length + 2*wall; h = height + 2*wall; r = (radius > 0 ? radius + wall:0);
// Get actuall lid measurments
lidh=h*lidp/100; liph= h*lipp/100;

/* [Advanced] */

// Only round the sides of the box?
sidesonly=1; // [0:No, 1:Yes]

// How snugly should the parts fit?
fit = 0; // [0:Super fit, 0.2:Force fit, 0.3:Hold fit, 0.4:Slide fit, 0.5:Free fit]

// Should there be a gap inside so the outside lips fit flush? (This does not change the hight of the box)
gap= 0; // [0:No gap, 0.1:Small gap, 0.3:Medium gap, 0.5:Large gap]

// How far to seperate the pices when printing both
seperation = 2;

// Number of segments in a circle
$fn = 50;

/* [Hidden] */

// Fudge Factor
x= 0.1;

// translate([0,0, 5]) boxlip(width, length, height, wall/2, radius, lidh, lidh+liph); // Test lip

boxWithLid(w, l, h, wall, r, sidesonly, 1);
boxWithLid(w, l, h, wall, r, sidesonly, 2);

// Make a hollow box with a lid
module boxWithLid(width, length, height, wall, radius, sidesonly, part) {
	w = 2*wall;
	// This just flips the top upside down to print side by side with the bottom
	translate([(part < 3 ? (part-1.5):0)*(width+seperation), 0, 0]) rotate(a=[(part==1 ? 1:0)*180, 0, 0]) {
		difference() {
    	    		hollowbox(width, length, height, wall, radius, sidesonly=sidesonly);
			if (part == 1) difference() {		// Subtrack bottom of box to make top
				cube([width+x, length+x, height+x], center=true);
				translate([0, 0, (height-lidh+x)/2]) cube([width+x, length+x, lidh+x], center=true);
				boxlip(width+x, length+x, height+x, (wall-fit+x)/2, radius+x, lidh, liph);
			}
			if (part == 2) {			// Subtrack top of box to make bottom
				translate([0, 0, (height-lidh-gap+x)/2]) cube([width+x, length+x, lidh+gap+x], center=true);
				boxlip(width+x, length+x, height+x, (wall+fit+x)/2, radius+x, lidh, liph);
			} 					// Else Make the whole box
		}
	}
}

// Make a hollow box
module hollowbox(width, length, height, wall, radius) {
    w = 2*wall;

	if (radius > 0) difference() {
		roundedBox([width, length, height], radius, sidesonly=sidesonly);
		roundedBox([width-w, length-w, height-w], radius-wall, sidesonly=sidesonly);
	} else difference() {
        cube([width, length, height], center=true);
        cube([width-w, length-w, height-w], center=true);
	}
}

// Make the lip btween the top and bottom
module boxlip(width, length, height, wall, radius, top, thick) {
	w = 2*wall;

	intersection() {
		hollowbox(width, length, height, wall, radius);
		translate([0,0,(height-thick)/2-top]) cube([width+x, length+x, thick], center=true);
	}
}

```


[User]
Okay, I have an OpenSCAD design here that I'd like to modify and make more robust, and also add some useful features.

Basically, I have a sphere that's cut into two halves, with a pin and hole system connecting them. The file, `sphere-halves.scad`, is included. It's got a couple of issues, though.

First, it's tricky to remove from the build plate because of the flat bottoms. I'd like to explore options to address that, perhaps adding a small chamfer or rounded edge.

Second, the pin and hole, while functional, are pretty basic and I think I want it to be tighter. I'm finding the pin wiggles a bit, making it feel a little flimsy. I'd like a tighter fit and maybe consider some more advanced techniques for alignment.

Third, the code itself is pretty verbose. The mirrored halves are essentially the same code repeated, just translated. I'm wondering if we could do something with modules or loops or some other structure in OpenSCAD to make it easier to modify and maintain in the future. I also have some ideas for additional variations I'd like to be able to generate in the future.

Here's what I'd like in terms of a new design and a new OpenSCAD file:

**Key Requirements:**

1.  **Parametric Sphere Radius:** Like my existing code, I'd like the sphere radius to be a primary parameter that the user can easily adjust. I plan on generating different sized globes and balls.
2.  **Two Halves:** The design should still be made of two halves.
3.  **Improved Pin and Hole:**  The pin and hole should have a tighter fit, reducing wiggle. It would also be nice if there was some sort of alignment feature to ensure that the two halves line up nicely, perhaps a chamfered or beveled edge.
4.  **Rounded Bottoms:** Instead of completely flat bottoms on each sphere half, I want a very small chamfer or fillet so that they are easier to remove from the build plate without excessive force, making removal safer and easier.
5.  **Modular Design:** The code should be structured with modules to reduce code duplication and make it easier to modify and add new features.
6.  **Configurability:** I'd like to be able to configure the size of the pin and hole, as well as the height and size of the chamfer or fillet on the bottom.
7. **Library Usage:**  I'm open to leveraging any appropriate libraries to facilitate this, specifically I am thinking of BOSL2 since I've used that before, but if you have other library suggestions I'm open to them, especially any that have advanced features like alignment helpers.

**Optional/Future Features (Nice to have, but not critical right now):**

*   Different pin and hole shapes (e.g. a hexagonal peg/hole for very tight fit).
*   The option for a slight twist locking mechanism between halves.
*   The ability to generate a ball with no pin or hole at all (a complete sphere) for testing and for use as a separate project.

So, could you provide an OpenSCAD file that implements these features? I'm excited to see what we can come up with!

[Assistant]
sphere-halves.scad:
```

// preview[view:south west, tilt:bottom diagonal]

// Radius of cube in mm (Must be 10mm or bigger)
cube_radius=20;

rotate([180,0,0]) {
translate([cube_radius+5,0,0])
difference() {
difference() {
sphere(cube_radius, $fn=100);
translate([-cube_radius,-cube_radius,0]) cube(cube_radius*2);
}
translate([0,0,-6]) cylinder(h=6.1,r=3.05,$fn=30);

}

translate([-cube_radius-5,0,0])
difference() {
difference() {
sphere(cube_radius, $fn=100);
translate([-cube_radius,-cube_radius,0]) cube(cube_radius*2);
}
translate([0,0,-6]) cylinder(h=6.1,r=3.05,$fn=30);
}

union() {
translate([0,0,-1.5]) cylinder(h=1.5,r1=3,r2=2.5,$fn=30);
translate([0,0,-10]) cylinder(h=8.5,r=3,$fn=30);
translate([0,0,-11.5]) cylinder(h=1.5,r1=2.5,r2=3,$fn=30);
}
}

```


[User]
Okay, so I'm trying to design a set of knitting needles in OpenSCAD, and I've got a basic design working, but I need it to be much more flexible and user friendly. I'm not super familiar with all the OpenSCAD tricks, so I'd really appreciate some help making it parametric and robust.

Right now, my design consists of two main parts: the needle itself, and a cap for the blunt end. The needle is a cylinder that tapers to a point, and the cap fits over the base of the needle. I'd like to be able to easily adjust all the dimensions, and also be able to generate a single needle or a pair, so I need help making this a good parametric design.

Here's what I've got so far, and some more of what I would like to be able to customize:

**Needle Body**

*   **`BODY_LENGTH`**:  This is the total length of the needle, without the tip.
*   **`BODY_DIAMETER`**: This is the diameter of the main cylindrical part of the needle.
*   **`TIP_TAPER_LENGTH`**: This is the length of the tapered cone that forms the needle tip.
*   **`TIP_DIAMETER`**: This is the diameter of the very tip of the needle. It's always smaller than `BODY_DIAMETER`.
*   **Needle Orientation:** Currently the needle is rotated to lay at a 45 degree angle to make printing easier, it would be nice to be able to control that or remove it, in case a user wanted a straight needle.
*   **Tip Style:** The tip is currently a cone, but it would be nice to be able to easily make a more rounded or bullet shaped tip if someone wanted it. This could be an additional shape selection or some parameters for the cone shape.

**Cap**

*   **`SLEEVE_LENGTH`**: The length of the cylindrical sleeve part of the cap that fits over the needle base.
*   **`SLEEVE_THICKNESS`**: The thickness of the sleeve wall.
*   **`TOP_DIAMETER`**: The diameter of the top (flat circular part) of the cap.
*   **`TOP_THICKNESS`**: The thickness of the flat top of the cap.
*   **Cap Placement:** The cap's initial location is a bit complicated because it's calculated based on the needle diameter, sleeve length and top thickness. It would be nice to make it a little more straightforward to position and perhaps not require the calculation, or provide a secondary way to position it.

**General**

*   **`TWO_NEEDLES`**: A boolean flag to generate either one or two needles and caps.
*   **Parametric Control:** I'd like all the dimensions to be easily adjustable via variables so that a user can quickly create needles with custom sizes.
*   **Clear Comments:** It would be great if the code could be clearly commented so that I and other users can understand what it's doing.
*   **Error Handling:** Simple error handling would be useful for cases where the dimensions might not make sense (e.g. TIP_DIAMETER > BODY_DIAMETER).
*   **Unit System:** Explicitly showing a unit system might be useful for the user, probably in millimeters.

**Libraries**
*   Please do not use external libraries.

So, to summarize, I’m looking for a clean, parameterized OpenSCAD file that generates one or two knitting needles and their caps, with easily adjustable dimensions, and ideally an option for different tip shapes.  The parameters I listed above should be adjustable, and there should be error handling and good commenting. Can you help me with that?

[Assistant]
knit_needle.scad:
```
$fn = 100;						// 100 sides on a circle
BODY_LENGTH = 250;			// Length of needle
BODY_DIAMETER = 5;			// Diameter of needle
TIP_TAPER_LENGTH = 15;		// Length of tapered portion
TIP_DIAMETER = 1;				// Diameter of tip end
SLEEVE_LENGTH = 3;			// Length of cap sleeve (overlaps needle body)
SLEEVE_THICKNESS = 1;		// Thickness of sleeve
TOP_DIAMETER = 10;			// Diameter of top
TOP_THICKNESS = 1;			// Thickness of top
TWO_NEEDLES = true;			// Generate two needles?

translate(v = [BODY_DIAMETER / 2, BODY_DIAMETER / 2, 0])
{
	needle();
}

if(TWO_NEEDLES)
{
	translate(v = [-(BODY_DIAMETER / 2), -(BODY_DIAMETER / 2), 0])
	{
		needle();
	}
}

// Calculate cap positioning.
capOffset = (TOP_DIAMETER / 2) + BODY_DIAMETER;
capDepth = -((BODY_DIAMETER / 2) - (SLEEVE_LENGTH / 2) - TOP_THICKNESS);

translate(v = [capOffset, capOffset, capDepth])
{
	cap();
}

if(TWO_NEEDLES)
{
	translate(v = [-capOffset, -capOffset, capDepth])
	{
		cap();
	}
}

module needle()
{
	// Adjust to lay flat on 45 degree angle (ideal for printing as long as possible).
	rotate(a = [90, 0, 45])
	{
		// Build main needle body and tip.
		union()
		{
			// Create needle body.
			cylinder(r = BODY_DIAMETER / 2, h = BODY_LENGTH - TIP_TAPER_LENGTH, center = true);

			// Add tip.
			translate(v=[0, 0, BODY_LENGTH / 2])
			{
				cylinder(r1 = BODY_DIAMETER / 2, r2 = TIP_DIAMETER / 2, h = TIP_TAPER_LENGTH, center = true);
			}
		}
	}
}

module cap()
{
	union()
	{
		// Create sleeve.
		difference()
		{
			cylinder(r = (BODY_DIAMETER + SLEEVE_THICKNESS) / 2, h = SLEEVE_LENGTH, center = true);
			cylinder(r = BODY_DIAMETER / 2, h = SLEEVE_LENGTH, center = true);
		}

		// Add top.
		translate(v = [0, 0, -((SLEEVE_LENGTH / 2) + (TOP_THICKNESS / 2))])
		{
			cylinder(r = TOP_DIAMETER / 2, h = TOP_THICKNESS, center = true);
		}
	}
}
```


[User]
Okay, I'm looking to create a customizable child safety latch that I can 3D print. I want it to work by having two knobs on either side of a door or cabinet, and a clip that slides onto those knobs to hold the door closed.

The design should consist of a main body that is essentially a flat bar with cylindrical ends. One end needs to be a slightly tighter fit than the other, allowing that end to act as a hinge when the latch is used. The other end will act as the hook or latch, sliding onto the second knob.

Here's a more detailed breakdown of what I need:

*   **Knobs:** The latch attaches to two knob-like protrusions. I need to be able to customize the diameter of these knobs (the `knob_diameter` parameter in the provided code), but the hole in the latch for the 'hinge' knob should be slightly larger than the hole for the 'latch' knob to allow it to move. The latch should slide on to the knobs and only be released from the knobs with the latch rotated to it's maximum range of motion.
*   **Distance:** I need to be able to specify the distance between the knob centers (the `knob_distance` parameter in the provided code).
*   **Main Body:** The main body of the latch should be a flat extrusion that connects the cylindrical ends. It needs to be strong enough to resist a child's attempts to open it. The width and height should scale with the knob diameter to ensure a secure fit.
*   **Hole Creation:** The holes for the knobs should be created by subtracting cylindrical volumes from the body of the latch. The 'hinge' hole should be slightly larger than the 'latch' hole as noted above.
*   **No Additional Hardware:** The entire latch should be 3D printable in one piece, with no need for any extra parts like screws or springs.
*   **Build Plate:** Since this is to be 3D printed, I need to make sure to make the build plate selection is available as a configurable parameter and can change size based on selections. I need to be able to select between a Replicator 2, Replicator, Thingomatic, and Manual build plates. The manual build plate selection needs to have configuration options for the build plate's x and y dimensions.

I'd like an OpenSCAD file that I can modify to adjust all of these parameters. I also need to be able to render the object with a build plate for visualization purposes. Please include the `utils/build_plate.scad` library.

Also include safety considerations in the comment section of the generated code to make sure users know that it's not baby proof but can be used as a baby resistant solution.

Could you generate the OpenSCAD code for this?

[Assistant]
Customizable_Child_Safety_Latch.scad:
```
$fn=30*1;

// Just for the customizer

use <utils/build_plate.scad>

//for display only, doesn't contribute to final object
build_plate_selector = 0; //[0:Replicator 2,1: Replicator,2:Thingomatic,3:Manual]

//when Build Plate Selector is set to "manual" this controls the build plate x dimension
build_plate_manual_x = 100; //[100:400]

//when Build Plate Selector is set to "manual" this controls the build plate y dimension
build_plate_manual_y = 100; //[100:400]

build_plate(build_plate_selector,build_plate_manual_x,build_plate_manual_y);

// The real thing

// knob_diameter = the diameter of the knob bases
knob_diameter=10; //[8:16]

// knob_distance = the distance between the knob bases measured from the nearest edges
knob_distance=80; //[50:120]

translate([0,0,2.5]) safety_clip(length=knob_distance, knob_d=knob_diameter);

module safety_clip(length, knob_d=9) {
  knob_r=(knob_d+1)/2;

  difference() {
    union() {
      // The frame
      difference(){
        linear_extrude(height=5,center=true)
            polygon(points=[[-length/2-knob_r,-knob_d],[-length/2-knob_r,knob_d-1],[length/2+knob_r,knob_d+1],[length/2+knob_r,-(knob_d+2)]]);
        hull(){
          translate([-(length/2-knob_d),-(knob_d-6),-4]) cylinder(r=2,h=8);
          translate([-(length/2-knob_d/1.58),knob_d-6,-4]) cylinder(r=2,h=8);
          translate([length/2-knob_d/1.465,knob_d-6,-4]) cylinder(r=2,h=8);
          translate([length/2-knob_d,-(knob_d-6),-4]) cylinder(r=2,h=8);
        }
      }

      // The latching end
      translate([-length/2-knob_r,0,0]) cylinder(r=knob_d,h=5,center=true);

      // The slightly larger pivoting end
      translate([length/2+knob_r,0,0]) cylinder(r=knob_d+2,h=5,center=true);
    }

    // The hole for the latching end
    translate([-length/2-knob_r,0,0]) cylinder(r=knob_r,h=7,center=true);
    translate([-length/2-knob_r,5,0]) linear_extrude(height=9,center=true)
        polygon(points=[[-knob_r,-5],[knob_r,-5],[knob_r/1.58,knob_r+3],[-knob_r/1.58,knob_r+3]]);

    // The slightly narrower hole for the pivoting end
    translate([length/2+knob_r,0,0]) cylinder(r=knob_r,h=7,center=true);
    translate([length/2+knob_r,5,0]) linear_extrude(height=9,center=true)
        polygon(points=[[-knob_r,-5],[knob_r,-5],[knob_r/1.465,knob_r+5],[-knob_r/1.465,knob_r+5]]);
  }

}
```


[User]
Okay, I'd like to design a crown in OpenSCAD, and it needs to be compatible with Ring-A-Thing. I'm thinking something that looks regal but also printable.

Here's what I have in mind:

**Basic Structure:**

*   **Body:** A cylindrical base for the crown. The height and inner/outer radius should be parametric.
*   **Flanges:** I'd like decorative flanges on both the top and bottom edges. I was thinking of using a series of circular extrudes with an overlapping square cutout to give a sort of scalloped effect. I need the radius of the circular extrudes to be a parameter.
*   **Spikes:** A number of spike-like protrusions extending upwards from the top of the body. The number, height, and profile of these spikes should all be adjustable. The base of each spike should be a slightly rounded triangular shape, not a sharp point.
*   **Pearls:** Small spherical "pearls" on the top of each spike. Their radius should be a parameter as well.
*   **Gems:** Several small sphere-like "gems" embedded into the cylindrical body of the crown, probably around the "equator." The placement of these should be parametric, probably based on the number of spikes, to help give the feeling of balance.
*   **Text:** I want to have my name engraved into the body of the crown, using the `writecylinder()` function from the `write.scad` library.

**Ring-A-Thing Compatibility:**

*   A small cutout needs to be added to the inside of the crown, at the bottom, that would act as a connector for Ring-A-Thing. This is especially important for smaller crowns. I would want the size and location to be configurable.

**Parametric Requirements:**

*   Inner radius of the crown's body.
*   Outer radius of the crown's body.
*   Height of the crown's body.
*   Text to be written on the crown.
*   Radius of the flange's circular feature.
*   Number of spikes.
*   Height of the spikes.
*   Radius of the pearls on top of spikes.
*   Number of gems.
*   Radius of the gems.
*  The size of the Ring-A-Thing connector cutout

**Specific Library Used:**

*   I'll be using the `write.scad` library for the `writecylinder` function.

**Additional Notes:**

*   I want to make sure all the important parts are parameterized and easy to adjust. I’d also prefer if the code is readable, with comments to explain what's going on.

Could you help me generate a parametric OpenSCAD file based on these specifications?

[Assistant]
CrownRing.scad:
```
include <write.scad>

/////////// START OF PARAMETERS /////////////////

// Inner radius
inner_radius=4.1;

// Body height
body_height=10;

// Text
text="name";

// Radius of facets
facet_radius=1;

// # of spikes
aantal_spikes=6;

// Height of spikes
hoogte_spikes=10;

/////////// END OF PARAMETERS /////////////////

outer_radius=inner_radius+2;

$fn=20;
pi=3.1415926;
pi2=pi*2;

// Flens Top
translate([0,0,-(body_height/2)+facet_radius]){
	difference(){
		rotate_extrude()
		translate([outer_radius, 0, 0])
			circle(r = facet_radius,$fn=15);
			rotate_extrude()
				translate([outer_radius-(2*facet_radius), -facet_radius, 0])
				square(2*facet_radius);
				}
	}

// Flens Bottom
translate([0,0,(body_height/2)-facet_radius]){
	difference(){
		rotate_extrude()
		translate([outer_radius, 0, 0])
			circle(r = facet_radius,$fn=15);
			rotate_extrude()
				translate([outer_radius-(2*facet_radius), -facet_radius, 0])
				square(2*facet_radius);
				}
	}

//Gems    3 gems=[5:7]  5 gems=[4:8]
for (i = [5:7]) {
	translate([sin(360*i/6)*(outer_radius-.5), cos(360*i/6)*(outer_radius-.5), 0 ]) sphere(r = body_height/7.5,$fn=6);
}

//Body
difference(){
translate([0,0,0]){
cylinder(r=outer_radius,h=body_height,center=true);
writecylinder(text,[0,0,0],t=1.5,outer_radius,center=true);
}
cylinder(r=inner_radius,h=body_height,center=true);
translate([0,0,-0.5*body_height+6.35]) cylinder(r=4.7,h=4); //Inkeping tbv connector
}

//Spikes

difference(){
translate([0, 0, .499*body_height]) {
	for (i = [0:aantal_spikes]) {
		rotate([90,0,360/aantal_spikes*i])
		linear_extrude(height = outer_radius, center = false)
			polygon(points=[[-pi*inner_radius/aantal_spikes,0],[pi*inner_radius/aantal_spikes,0],[0,hoogte_spikes]]);
		}
	}

cylinder(r=inner_radius,h=body_height+3*hoogte_spikes,center=true);        //Cut out spikes inner
difference(){cube(200,center=true);cylinder(h=50,r=outer_radius,$fn=20);}  //Cut out spikes outer
}

//Pearls on top of spikes
pos=(outer_radius-inner_radius)/2+inner_radius;
translate([0, 0, 0]) {
	for (i = [0:aantal_spikes]) {
translate([sin(360*i/aantal_spikes)*(pos), cos(360*i/aantal_spikes)*(pos),.5*body_height+hoogte_spikes-1])
sphere(1.5,$fn=10);
}}

```


[User]
Okay, I'm looking to design a servo horn that can pull a cable or string. I need it to be customizable, and I want it to include the servo spline mount as part of the 3D printed piece, not a separate part.

Here's what I'm thinking:

**General Shape:**

*   The main body will be a partial wheel (like a section of a cylinder) with an opening to allow for cable pulling.
*   I'll need to specify the angle of the "pie slice" that's left over after the opening (the part that's *not* removed). This dictates how much rotation of the servo translates into cable pulling.
*   It needs a notched rim to guide the cable/string.
*   The design also needs tie-off points for the cable/string near the notch, kind of like little holes you can thread the cable through.

**Specific Parameters I'd like to control:**

*   `angle`: The angle in degrees of the usable "pie slice" of the wheel, which determines the range of motion when pulling the cable (e.g., 120 degrees).
*   `cable_diameter`: The diameter of the cable/string being pulled.
*   `notch_depth`: The depth of the notch in the wheel rim where the cable sits.  This needs to be at least as big as the cable diameter.
*   `wheel_diameter`: The overall diameter of the partial wheel.
*   `wheel_height`: The height or thickness of the wheel. It should probably be at least twice the notch depth.
*   `servo_mount_diameter`: How much space is around the servo spline to allow for attachment. Needs to be bigger than 6mm.
*   `num_teeth`: The number of teeth on the servo spline. I’ve only tested with 25 teeth, but I’d like to use other servos if this works well.

**Spline Details:**

*   The design MUST include the servo spline as a female socket, designed to fit directly onto the servo. I think it should be compatible with standard servo spline dimensions for servos with the `num_teeth` value I set.
*   I'm thinking there should be a countersunk screw hole through the center of the spline for servo attachment.

**Tie-off Points:**

*   I want to have two holes for tying off the cable, one at either end of the cut out section.
*   These holes should be a bit offset from the notch. They should come up from behind the notch.
*    Their diameter should be approximately the size of `cable_diameter`

**Additional Details:**

*   The edges where the "pie slice" is cut need to have some additional filler material to make it look a bit nicer (concave edges).
*   I am interested in this being parametric such that, for example, if the notch height increased, other dimensions would compensate as needed.

Could you generate an OpenSCAD file for this? I don't need any external libraries, just straight OpenSCAD code, please. I think it would make sense if the spline generation was in a `module` to make the main code cleaner, but other than that, it should all be in one `.scad` file.

[Assistant]
cable-pulling_servo_horn.scad:
```
//---------------------------------------------------------------------------------
//-- Cable-pulling Servo Horn
//-- By William M. Hilton (wmhilton) wmhilton@gmail.com / wmhilton@drexel.edu
//-- Derived from "Servo wheel" by Juan Gonzalez (obijuan) juan@iearobotics.com
//---------------------------------------------------------------------------------
//-- A partial wheel with tie-off points, so that a servo can pull a cable.
//---------------------------------------------------------------------------------

// Customizable parameters
// The amount of degrees which you want to be able to pull.
angle = 120;
// The diameter of the cable or line being pulled.
cable_diameter = 0.75;
// The depth of the notch in the wheel. Should be >= your cable diameter.
notch_depth = 1.7;
// The outer diameter of the wheel.
wheel_diameter = 40;
// The height of the wheel. Should be >= 2*notch_depth.
wheel_height = 6;
// How much material you want around the spline connection. Has to be > 6mm.
servo_mount_diameter = 10;
// I ONLY TESTED WITH A 25 TOOTH SERVO. I have no idea if this would generate a reasonable 23 or 24 tooth horn.
num_teeth = 25;

// Computed parameters
cable_radius = cable_diameter/2;
wheel_radius = wheel_diameter/2;
servo_mount_radius = servo_mount_diameter/2;
// Calculate notch dimensions
//notch_depth = cable_radius + cable_radius*sqrt(2);
notch_height = 2*notch_depth;
inner_radius = wheel_radius - notch_depth;
//wheel_height = 2*notch_height;
// Calculate trimming dimensions
extra_theta = asin(servo_mount_radius/wheel_radius);
true_angle = angle+2*extra_theta;
// Calculate tie off hole placement. Tie off holes are 2mm in from the notch radius.
hole_enter_distance = inner_radius + cable_radius*sqrt(2);
hole_exit_x = inner_radius*cos(extra_theta) - 2 - cable_radius;
hole_angle = atan((hole_enter_distance - hole_exit_x)/servo_mount_radius);
//hole_offset_y = hole_exit_distance*sin(extra_theta);
//hole_offset_x = hole_enter_distance - hole_exit_distance*cos(extra_theta);
//hole_angle = atan(hole_offset_x/hole_offset_y);

main();

module main() {
	difference() {
		union() {
			rotate([0,0,-extra_theta])
			difference() {
				// Base wheel.
				cylinder(r=wheel_radius,h=wheel_height,$fn=100);

				// Cut to angle.
				cut_pie(wheel_radius,wheel_height,true_angle);
			}

			// Give the servo attachment area some circular space.
			cylinder(r=servo_mount_radius,h=wheel_height,$fn=100);

			// Add filler material on sides to give it a nice concave look.
			translate([0,-servo_mount_radius,0])
			cube([wheel_radius*cos(extra_theta),servo_mount_radius,wheel_height]); // Bottom right edge

			rotate([0,0,angle])
			cube([wheel_radius*cos(extra_theta),servo_mount_radius,wheel_height]); // Left edge
		}

		// Put notch in rim.
		translate([0,0, wheel_height/2-notch_depth]) // Center along rim
		rotate_extrude($fn=100)
		polygon([[inner_radius,notch_height/2],[wheel_radius+1,notch_height+1],[wheel_radius+1,-1]]);

		// Subtract servo mount.
		servomount(counter_sink_height=wheel_height, counter_sink_diameter=7.0);

		// Holes for tying cable off.
		translate([hole_exit_x,-servo_mount_radius,wheel_height/2])
		rotate([0,0,-hole_angle])
		rotate([-90,0,0])
		translate([0,0,-2])
		cylinder(r=cable_diameter,h=wheel_diameter,$fn=6);

		mirror([cos(angle/2+90),sin(angle/2+90),0])
		translate([hole_exit_x,-servo_mount_radius,wheel_height/2])
		rotate([0,0,-hole_angle])
		rotate([-90,0,0])
		translate([0,0,-2])
		cylinder(r=cable_diameter,h=wheel_diameter,$fn=6);

	}
}

//---------------------------------------------------------------------------------
//-- Pie Cut
//-- By William M. Hilton (wmhilton) wmhilton@gmail.com / wmhilton@drexel.edu
//---------------------------------------------------------------------------------
//-- Generate a solid that can be subtracted from a cylinder to make a pie-shape.
//---------------------------------------------------------------------------------
module cut_pie(radius,height,degrees) {
	angle_to_remove = 360 - degrees;
	bite_size = 30;
	num_bites = ceil(angle_to_remove/bite_size);
	last_bite_size = angle_to_remove - bite_size*(num_bites-1);
	echo(str("angle_to_remove: ",angle_to_remove));
	echo(str("num_bites: ",num_bites));
	echo(str("last_bite_size: ",last_bite_size));
	if (angle_to_remove <= bite_size) {
		bite(angle_to_remove,radius,height);
	} else {
		for (i=[0:num_bites-2]){
			rotate([0,0,-i*bite_size])
			bite(bite_size+1,radius,height);
			echo(str("i=",i));
		}
		#rotate([0,0,-(num_bites-1)*bite_size])
		bite(last_bite_size,radius,height);
	}
}

module bite(delta,radius,height) {
	linear_extrude(height=height)
	polygon([
		[0,0],
		[radius,0],
		[radius,-radius*tan(delta)]
	]);
}

//---------------------------------------------------------------------------------
//-- Servo Spline (Female)
//-- By William M. Hilton (wmhilton) wmhilton@gmail.com / wmhilton@drexel.edu
//---------------------------------------------------------------------------------
//-- A negative model of the part of a servo horn that attaches to the splines.
//---------------------------------------------------------------------------------
module tooth(num_teeth, outer_diameter, inner_diameter) {
	// The .99 keeps the teeth from overlapping, which seems to cause tremendous trouble.
	polygon([
		[outer_diameter/2,0],
		[inner_diameter/2*cos(180/num_teeth), inner_diameter/2*sin(180/num_teeth)*.99],
		[inner_diameter/2*cos(180/num_teeth),-inner_diameter/2*sin(180/num_teeth)*.99]
	]);
}

module splinewheel(spline_height,num_teeth,outer_diameter,inner_diameter) {
	union() {
		linear_extrude(height=spline_height)
		for (i=[1:num_teeth])
		{
			rotate([0,0,i*360/(num_teeth)])
			tooth(num_teeth, outer_diameter, inner_diameter);
		}
		linear_extrude(height=spline_height)
		circle(r=inner_diameter/2,center=true,$fn=6*num_teeth);
	}
}

module servomount(counter_sink_height=1.5, counter_sink_diameter=6.0, num_teeth=25) {
	spline_height = 3.8;
	outer_diameter = 6.1; //This is what I increased from v1 to v2. Was 6.0, now 6.1. Hopefully it'll not be such a tight press fit.
	inner_diameter = 5.3;
	screw_diameter = 3.0;
	splinewheel(spline_height,num_teeth,outer_diameter,inner_diameter);
	cylinder(r1=outer_diameter/2,r2=0,h=outer_diameter/2,$fn=100);
	cylinder(r=screw_diameter/2,h=spline_height+0.9+counter_sink_height,$fn=100);
	translate([0,0,spline_height+0.9])
	cylinder(r=counter_sink_diameter/2,h=counter_sink_height,$fn=100);
}

```


[User]
Okay, I'm looking to design a custom insert for my Sortimo T-Boxx, and I'd like to use OpenSCAD to make it parametric. I've seen some designs online (I'll include them below) that are a good starting point, but I need something more flexible. I really want to be able to control the dimensions and make it exactly fit my needs, as well as customize peg layouts for different tools. I'm new to OpenSCAD, and I need something where I can change some parameters and easily generate different sizes. Here's what I'm aiming for:

**Basic Structure:**

*   The insert should consist of a rectangular box with rounded corners at the base and top. I want to control the roundness of both independently.
*   The insert should have a hollow inside, creating a wall of a specified thickness.
*   The insert should have holes in its base that can be used to mount it on the T-Boxx using pegs. These pegs are mounted on the base of the T-Boxx itself.
*   I need to be able to adjust the number of "modules" (sort of like the grid-spacing) wide and deep the insert is.
*   The size of the pegs (diameter) that slot into the T-Boxx base should be adjustable.

**Parametric Controls (the core of my needs):**

*   **Modules Wide (modulesH):**  This controls how many units wide the insert is. Imagine a grid system, this is the number of columns.
*   **Modules Deep (modulesV):** This controls how many units deep the insert is, the number of rows on the grid.
*   **Wall Thickness (wallThickness):**  Thickness of the walls of the insert, allowing me to control the sturdiness.
*   **Peg Diameter (pegDiameter):** Diameter of the pegs that fit into the T-Boxx base.
*    **Base Corner Diameter (baseCornerDiameter):** The size of the radius for the rounded corners on the bottom.
*    **Top Corner Diameter (topCornerDiameter):**  The size of the radius for the rounded corners at the top.
*   **Total Height (height):** The overall height of the insert. This is related to the top and bottom corner diameters.
*   **Peg Distance (pegDistance):**  The distance between the peg positions for the base, this is also a type of grid spacing that defines each unit. The overall width and depth of the insert will be the number of modules multiplied by the peg distance. This _should_ be a configurable parameter.
*   **Top Width, Top Lower Width, Bottom Width:** Parameters that define the top and bottom perimeters of the insert.

**Additional Requirements:**

*   I need the code to be relatively easy to understand. I'm a beginner, so commented code would be appreciated.
*   The code should be well-structured and use modules where appropriate.
*   I'd like to be able to render just the insert, or just the pegs or both. So I would need to have a selection of "boxx", "pegs", or "both"
*   I'd like to use the hull function to create smooth rounded corners between the different cylinders.
*   It looks like the original design was using spheres for some corners - I would be happy if this could be replaced by cylinders as well, or have the option to use cylinders, to simplify printing.

**Example Files:**

I have attached two files, `T-Boxx_Insert.scad` and `Boxx_Insert_v2.scad`, that are similar to what I want. I am including them for reference.
I think that these do not use any external libraries, but if you know of some that would simplify my design that would be amazing.

Could you help me create this OpenSCAD file?

[Assistant]
T-Boxx_Insert.scad:
```
// created by pretenda
// http://www.thingiverse.com/pretenda/designs

// If you are reading this, sorry for my spaghetti code.

// Options!

/* [T-Boxx Insert] */
// What do you want to render out?
what = "both"; // [boxx:Boxx Insert,pegs:Pegs,both:Both Boxx Insert and Pegs]
// How many units wide?
modulesH = 1; // [1:8]
// How many units deep?
modulesV = 1; // [1:6]

/* [Misc Parameters] */
// Wall Thickness. Too thin and it is a bit flimsy, 1.7 seems about right for me.
wallThickness = 1.7;
// Peg Diameter. This width for me is quite snug, might need to dial it down depending on your printer.
pegDiameter = 7.4;

/* [Hidden] */
pegDistance = 39.5;
baseCornerDiameter = 5;
topCornerDiameter = 10;
topWidth = 52.5;
topLowerWidth = 51.5;
topInnerDiameter = 48.5;
bottomWidth = 49.5;
height = 60.7;

pegSlackH = (modulesH - 1) * ((topWidth - pegDistance));
pegSlackV = (modulesV - 1) * ((topWidth - pegDistance));

blPosX = 0;
blPosY = 0;

brPosX = modulesH * pegDistance + pegSlackH;
brPosY = 0;

tlPosX = 0;
tlPosY = modulesV * pegDistance + pegSlackH;

trPosX = modulesH * pegDistance + pegSlackH;
trPosY = modulesV * pegDistance + pegSlackH;

// Pegs?!
/*translate([0,0,-2]) {
cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([brPosX, 0, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([0, tlPosY, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([trPosX, trPosY, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
}*/

module boxx()
{

difference()
{

union()
{
hull()
{
translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([brPosX, brPosY, 0]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([tlPosX, tlPosY, 0]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([trPosX, trPosY, 0]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

// Bottom
translate([blPosX, blPosY, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([brPosX, brPosY, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX, tlPosY, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([trPosX, trPosY, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);
}

hull()
{

translate([blPosX, blPosY, height]) translate([-(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([brPosX, brPosY, height]) translate([(topWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX, tlPosY, height]) translate([-(topWidth - pegDistance) / 2 + topCornerDiameter / 2, (topWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([trPosX, trPosY, height]) translate([(topWidth - pegDistance) / 2 - topCornerDiameter / 2, (topWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

}
}

 // inside carved out
hull()
{
translate([blPosX +wallThickness, blPosY + wallThickness, 1]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([brPosX - wallThickness, brPosY + wallThickness, 1]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([tlPosX + wallThickness, tlPosY - wallThickness, 1]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([trPosX - wallThickness, trPosY - wallThickness, 1]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

// Bottom
translate([blPosX + wallThickness, blPosY + wallThickness, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([brPosX - wallThickness, brPosY + wallThickness, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX + wallThickness, tlPosY - wallThickness, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([trPosX - wallThickness, trPosY- wallThickness, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);
}

// Holes for pegs to slot into

cylinder(20, 2, 2, $fn = 20);
translate([brPosX, 0, 0]) cylinder(20, 2, 2, $fn = 20);
translate([0, tlPosY, 0]) cylinder(20, 2, 2, $fn = 20);
translate([trPosX, trPosY, 0]) cylinder(20, 2, 2, $fn = 20);

}
}

module peg() {
union()
{
cylinder(2, pegDiameter/2, pegDiameter/2, $fn = 20);
translate([0,0,1]) cylinder(2, 1.8, 1.8, $fn = 20);
}
}

if (what == "boxx" || what == "both")
{
// Boxx!

boxx();

}

if (what == "pegs" || what == "both")
{
// Pegs!
translate([-20,0,0]) {
translate([0, 0, 0]) peg();
translate([0, pegDiameter + 2, 0]) peg();
translate([0, (pegDiameter+2)*2, 0]) peg();
translate([0, (pegDiameter+2)*3, 0]) peg();
}

}
```
Boxx_Insert_v2.scad:
```
// created by pretenda
// http://www.thingiverse.com/pretenda/designs

// If you are reading this, sorry for my spaghetti code.

// Options!
//cube([39.5,92,50]);
/* [T-Boxx Insert] */
// What do you want to render out?
what = "boxx"; // [boxx:Boxx Insert,pegs:Pegs,both:Both Boxx Insert and Pegs]
// How many units wide?
modulesH = 1; // [1:8]
// How many units deep?
modulesV = 3; // [1:6]

/* [Misc Parameters] */
// Wall Thickness. Too thin and it is a bit flimsy, 1.7 seems about right for me.
wallThickness = 1.7;
// Peg Diameter. This width for me is quite snug, might need to dial it down depending on your printer.
pegDiameter = 7.4;

/* [Hidden] */
pegDistance = 39.5; //92 for two -- so 13 difference
baseCornerDiameter = 5;
topCornerDiameter = 10;
topWidth = 52.5;
topLowerWidth = 51.5;
topInnerDiameter = 48.5;
bottomWidth = 49.5;
height = 60.7;

pegSlackH = (modulesH - 1) * 13;
pegSlackV = (modulesV - 1) * 13;

blPosX = 0;
blPosY = 0;

brPosX = modulesH * pegDistance + pegSlackH;
brPosY = 0;

tlPosX = 0;
tlPosY = modulesV * pegDistance + pegSlackV;

trPosX = modulesH * pegDistance + pegSlackH;
trPosY = modulesV * pegDistance + pegSlackV;

// Pegs?!
/*translate([0,0,-2]) {
cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([brPosX, 0, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([0, tlPosY, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
translate([trPosX, trPosY, 0]) cylinder(2, pegDiameter / 2, pegDiameter / 2);
}*/

module boxx()
{

difference()
{

union()
{
hull()
{

translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, 0.03]) #cylinder(2, baseCornerDiameter/2,baseCornerDiameter/2, $fn = 20);

translate([brPosX, brPosY, 0]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, 0.03]) #cylinder(2, baseCornerDiameter/2,baseCornerDiameter/2, $fn = 20);

translate([tlPosX, tlPosY, 0]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, 0.03]) #cylinder(2, baseCornerDiameter/2,baseCornerDiameter/2, $fn = 20);

translate([trPosX, trPosY, 0]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, 0.03]) #cylinder(2, baseCornerDiameter/2,baseCornerDiameter/2, $fn = 20);

// Bottom
translate([blPosX, blPosY, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([brPosX, brPosY, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX, tlPosY, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([trPosX, trPosY, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);
}

hull()
{

translate([blPosX, blPosY, height]) translate([-(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([brPosX, brPosY, height]) translate([(topWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX, tlPosY, height]) translate([-(topWidth - pegDistance) / 2 + topCornerDiameter / 2, (topWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

translate([trPosX, trPosY, height]) translate([(topWidth - pegDistance) / 2 - topCornerDiameter / 2, (topWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(4, topCornerDiameter / 2 -0.2, topCornerDiameter / 2, $fn = 30);

}
}

 // inside carved out
hull()
{
translate([blPosX +wallThickness, blPosY + wallThickness, 1]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([brPosX - wallThickness, brPosY + wallThickness, 1]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, -(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([tlPosX + wallThickness, tlPosY - wallThickness, 1]) translate([-(bottomWidth - pegDistance) / 2 + baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

translate([trPosX - wallThickness, trPosY - wallThickness, 1]) translate([(bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, (bottomWidth - pegDistance) / 2 - baseCornerDiameter / 2, baseCornerDiameter / 2]) sphere(baseCornerDiameter/2, $fn = 20);

// Bottom
translate([blPosX + wallThickness, blPosY + wallThickness, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([brPosX - wallThickness, brPosY + wallThickness, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([tlPosX + wallThickness, tlPosY - wallThickness, height]) translate([-(topLowerWidth - pegDistance) / 2 + topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);

translate([trPosX - wallThickness, trPosY- wallThickness, height]) translate([(topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, (topLowerWidth - pegDistance) / 2 - topCornerDiameter / 2, -4]) cylinder(5, topCornerDiameter / 2, topCornerDiameter / 2, $fn = 30);
}

// Holes for pegs to slot into

cylinder(20, 2, 2, $fn = 20);
translate([brPosX, 0, 0]) cylinder(20, 2, 2, $fn = 20);
translate([0, tlPosY, 0]) cylinder(20, 2, 2, $fn = 20);
translate([trPosX, trPosY, 0]) cylinder(20, 2, 2, $fn = 20);

}
}

module peg() {
union()
{
cylinder(2, pegDiameter/2, pegDiameter/2, $fn = 20);
translate([0,0,1]) cylinder(2, 1.8, 1.8, $fn = 20);
}
}

if (what == "boxx" || what == "both")
{
// Boxx!

boxx();

}

if (what == "pegs" || what == "both")
{
// Pegs!
translate([-20,0,0]) {
translate([0, 0, 0]) peg();
translate([0, pegDiameter + 2, 0]) peg();
translate([0, (pegDiameter+2)*2, 0]) peg();
translate([0, (pegDiameter+2)*3, 0]) peg();
}

}
```


[User]
Okay, I've got a pretty good idea for a picture frame, and I'd like to get an OpenSCAD file that I can easily adjust for different picture sizes.  I'm not looking for a full border frame, but more like a set of brackets that will hold a picture sandwich (picture + backing) against the wall.

Here's the basic idea:  I want a bracket that has a rounded rectangular shape, mostly flat, with a lip that comes up a little to hold the picture and backing in place. The bracket will essentially sandwich the picture between the bracket itself and the wall. The main body of the bracket needs to be thick enough to be strong, but not too bulky. I'd also like a hole for a cord to thread through so I can hang the picture, and maybe a little monogram on one side.

Here are the parameters I'd like to control, and their approximate current values:

*   **`T`**: Thickness of the cord used for hanging. Let's start with 1.5 mm.
*   **`w`**:  The overall width and depth of the bracket. This should be a square for symmetry. I'm thinking around 60 mm.
*   **`wall`**:  The thickness of the lip/wall that holds the picture in place.  Around 4 mm seems good.
*   **`minT`**: The minimum thickness of the picture "sandwich" (picture + backing). Let's say 5 mm to start.
*   **`maxT`**: The maximum thickness of the picture sandwich. Let's start with 10 mm.
*   **`r`**:  The radius of the rounded corners on the bracket. 2 mm should be nice.
*   **`Dhole`**:  The diameter of the hole for the hanging cord. It should be slightly larger than the cord thickness, say `T+2` mm, as a default value.

I need the bracket to have the following features:
1.  A rounded rectangular base, that is basically flat.
2. A lip, or raised wall, around the perimeter of the base to hold the picture. The inner area of the bracket should be wide enough for pictures and backing to fit.
3.  Two holes along the y and x axis to allow for hanging via a cord (or maybe a nail). I'd like these holes to be the same diameter. The hole location should be automatically derived such that a hole is located in the middle of each side of the base along the x and y axis, located slightly above the plane of the bracket.
4.  A small monogram/symbol on the bottom of the bracket. Let's try a stylized "M".
5.  The bracket needs to have sufficient depth to accommodate a reasonable depth of backing+picture.

Regarding libraries, I'd like to use the `MCAD/boxes.scad` library.

Could you create a parametric OpenSCAD file based on this description? I'd also like it to be easy to adjust the various parameters, so include all the parameters as defined variables at the start of the file, and add plenty of descriptive comments. Thanks!

[Assistant]
frame.scad:
```
// Thickness of cord
T=1.5;
// Width of bracket
w=60;
// Thickness of wall
wall=4;
// Minimum thickness of picture sandwich
minT=5;
// Maximum thickness of picture sandwich
maxT=10;
// radius of rounded edges
r=2;

Dhole=T+2;

use <MCAD/boxes.scad>

difference(){
	translate([0,0,maxT/2+T])roundedBox([w,w,maxT+2*T],r,$fn=16);
	difference(){
		translate([0,0,maxT+2*T])cube([w-2*wall,w-2*wall,2*maxT],center=true);
		translate([-w/2,-w/2+wall,2*T+minT])rotate([45,0,0])cube([w,maxT,maxT]);
		translate([-w/2+wall,-w/2,2*T+minT])rotate([0,-45,0])cube([maxT,w,maxT]);
	}
	rotate([0,0,45])translate([0,-w,-1])cube(2*w);
	translate([Dhole/2,0,w/4+T])cube(w/2,center=true);
	translate([0,Dhole/2,w/4+T])cube(w/2,center=true);
	translate(-(w/4-Dhole/2)*[1,1,0])cylinder(r=Dhole/2,h=2*maxT,center=true,$fs=1);
	translate([0,-w/2,(maxT+2*T)/2])rotate([90,0,0])monogram(h=0.6);
}

module monogram(h=1)
linear_extrude(height=h,center=true)
translate(-[3,2.5])union(){
	difference(){
		square([4,5]);
		translate([1,1])square([2,3]);
	}
	square([6,1]);
	translate([0,2])square([2,1]);
}
```


[User]
Okay, I need help designing a phone mount for my tripod. I've seen a design on Thingiverse that's close, but I need to make it parametric so I can easily adjust it for different phone and tripod sizes. I'd like the design to be in OpenSCAD.

Basically, the mount needs to have a base that fits my tripod's quick-release plate, and a top section that holds a phone securely. The phone is held in place by two parallel rectangular bars, creating a slot for the phone to slide into.

Here are the key features and parameters I need to control:

*   **`phone_width`**: The thickness of the phone, so I can set the correct gap between the holder bars.
*   **`base_width`**: The width of my tripod's quick-release plate base.
*   **`base_height`**: The height of the slanted part of the tripod mount base.
*   **`base_inset`**: The horizontal distance between the edge of the base and where the slope starts.
*   **`base_cutout`**: An additional amount to add to the bottom width before clipping the base, essentially how far the mount's base extends beyond the width of the tripod base.
*   **`holder_width`**: The width of the rectangular bars that hold the phone.
*   **`holder_height`**: The height of those same holding bars.

The base of the mount should have a slanted shape. Think of it like a squashed trapezoid, where the bottom is wider than the top. The code should generate this slanted shape using the `base_width`, `base_height`, `base_inset`, and `base_cutout` parameters. It then needs to be cut so that it is limited to the width of the tripod base `base_width`.

The phone holder consists of two parallel rectangular bars positioned on top of the base to create the slot for the phone. Their position is determined by the `base_inset` parameter and `phone_width`. I'd like to make sure there is a tiny bit of extra space between the holder bars so the phone can easily slide in (like maybe 0.05mm extra, you can call that `phone_width_2` to keep it separate).

I'd like this to be built using OpenSCAD with parametric variables at the start of the file so I can easily customize it without modifying the core code logic. I do not need any specific libraries.

Can you please provide me with the OpenSCAD code for this design? Thanks!

[Assistant]
iPhoneMount.scad:
```
// Phone width in mm (iPhone4/S=9.3, iPhone5=7.6, iPhone6=7.05)
phone_width=7.05;

// Width of the base of your tripod mount
base_width=43.25;

// Height of the slanted area of your tripod mount
base_height=9.1;

// Difference in width between the base and top of the mount
base_inset=4.1;

// Difference in width between the base bottom width and width if it hadn't been chopped off
base_cutout = 0.8;

// Width of the holder bars
holder_width=10;

// Height of the holder bars
holder_height=20;

base_width_2 = base_width + base_cutout;

phone_width_2 = phone_width + 0.05; // add a tiny bit of extra so phone can slide in

union() {

// base
intersection() {
    //slanted cube
	polyhedron(points=[[-base_cutout,-base_cutout,0],
                   [base_inset,base_inset,base_height],
                   [-base_cutout,base_width+base_cutout,0],
                   [base_inset,base_width-base_inset,base_height],
                   [base_width+base_cutout,base_width+base_cutout,0],
                   [base_width-base_inset,base_width-base_inset,base_height],
                   [base_width+base_cutout,-base_cutout,0],
                   [base_width-base_inset,base_inset,base_height]],
           triangles=[[2,1,0],[1,2,3],[4,3,2],[3,4,5],[6,5,4],[5,6,7],[0,7,6],[7,0,1],
				     [4,2,0],[0,6,4],[1,3,5],[5,7,1]]
           );

	//whatever the bigger shape, clip it to base_width
	cube([base_width,base_width,50]);
}

// phone holder
translate([base_inset,base_width-base_width/2-holder_width-phone_width/2,base_height])
	cube([base_width-base_inset*2,holder_width,holder_height]);
translate([base_inset,base_width-base_width/2+phone_width/2,base_height])
	cube([base_width-base_inset*2,holder_width,holder_height]);

}

```


[User]
Okay, I'm trying to design a 3D printable text plate using OpenSCAD, and I'm hoping you can help me create a parametric design. I want something that's like a "Hello World" plaque but with the ability to customize the text and some other aspects. I want to be able to simulate what a printer nozzle would be doing on the plate, too.

Here's a breakdown of the features I'd like, based on what I've seen in another design:

**Core Features:**

*   **Text Input:** I need to be able to specify the text that's printed on the plate. It should handle different lengths of text, and the plate width should adjust accordingly.
*   **Plate Thickness:** I need to control the thickness of the base plate.
*   **Text Spacing:** I need some space on the sides of the text, so the text is not right at the edges of the plate.
*   **Extruder Simulation:** I want to be able to visualize the position of the 3D printer extruder and nozzle. I should be able to set the X and Y position of the extruder on the plate. This is just for visual reference, not for printing itself (it's not actual gcode generation)
*   **Nozzle Resolution:** The nozzle will need a configurable resolution - for visualization, just like the extruder position.
*   **Hanging Hole:** I'd like an option to include a hole for hanging the plate, and be able to turn this option on or off.
*  **Style (Hollow or Solid):** I would like a parameter to control whether the plate underneath the text is a hollow base or a solid single-sided base.

*   **Base Style (None, Solid, or Foot):** I want three base style options, where the default is none, but I can also have a simple solid base or "feet" on the bottom of the plate.
*   **Output Style:** I want to be able to choose what gets rendered between: "text only", "plate only", or "both text and plate."

**Specific Details**

*   **Text Font:** I'd like to use the `8bit_polyfont()` found in the MCAD library, which I understand is a standard font library for OpenSCAD.
*   **Units:** Millimeters, ideally.
*   **Plate Shape:** A rectangular plate with rounded edges, kind of like a capsule shape.

**MCAD Library Usage:**

I know the existing design uses the `MCAD/shapes.scad` and `MCAD/fonts.scad` from the MCAD library. I believe I need `shapes` for making the plate itself and `fonts` for working with the text.

**Parameters to Control:**

I would like to control all of the following as parameters in the file:

*   `thickness`: The thickness of the plate.
*   `text`: The text to be printed.
*   `text_space`: The space between the text and the plate edges.
*   `extruder_xpos`: The x-coordinate of the extruder for visualization purposes.
*   `extruder_ypos`: The y-coordinate of the extruder for visualization purposes.
*   `nozzle_resolution`: The resolution of the nozzle for visualization.
*   `enable_hole`: A boolean to enable/disable the hanging hole.
*   `style`: An integer to choose between "hollow" and "single side" styles.
*   `base_style`: An integer to choose between "none", "solid", or "foot" styles.
*    `output_style`: An integer to choose between "text only", "plate only", or "both".
*    `plate_color`: Color of the plate.
*   `text_color`: Color of the text.
*   `printer_color`: Color of the printer elements (extruder, rod, build plate).

I think I covered everything. If you have questions, I'm happy to answer them. I'm looking forward to seeing the parametric OpenSCAD file you create.

[Assistant]
3d_printing_text_plate.scad:
```
// Copyright 2013 Glen Chung
// This file is licensed Creative Commons Attribution-ShareAlike 3.0.
// http://creativecommons.org/licenses/by-sa/3.0/legalcode

use <MCAD/shapes.scad>
use <MCAD/fonts.scad>

/* [Global] */

//plate thickness
thickness = 15;

//text to be printed (at least one character)
text = "HELLO WORLD";

//horizontal space to plate boundary
text_space = 10;

//extruder x position
extruder_xpos = 68;

//extruder y position
extruder_ypos = 54;  //[25:54]

//nozzle resolution
nozzle_resolution = 6;

//enable hanging hole
enable_hole = 0; //[1:true, 0:false]

//style (hollw or single side)
style = 1; //[0:hollow,1:singleside]

//base style
base_style = 2; //[0:none, 1:solid, 2:foot]

//output
output_style = 2; //[0:text only, 1:plate only, 2:both]

/* [Hidden] */
text_font = 8bit_polyfont();
indicies = search(text,text_font[2],1,1);
width = len(indicies)*32+text_space*2;
height = 67;
round_dia = 30;
rod_height = 5;
rod_thick = 10;
extruder_width = 28;
extruder_height = 18;
extruder_thick = thickness;
nozzle_dia = 7;
nozzle_height = 10;
text_scale = [4,5,3];
build_plate_width = len(indicies)*32;
build_plate_height = 8;
hanging_hole_size = 18;
plate_color = "Grey";
text_color = "Red";
printer_color = "Silver";

scale([0.2666,0.2666,0.3333]) {

if(output_style == 1 || output_style == 2) {
	difference() {
		union() {
			//plate
			translate([0, height/2, 0])
			difference() {
				color(plate_color)
				translate([-(width-round_dia)/2, -(height-round_dia)/2, -thickness/2])
					minkowski()
					{
 						cube([width-round_dia,height-round_dia,thickness/2]);
 						cylinder(r=round_dia,h=thickness/2);
					}

				translate([-(width)/2, -(height)/2, -thickness])
					cube([width,height,thickness*2]);
			}

			//x-rod
			translate([-width/2, extruder_ypos, -rod_thick/2]) color (printer_color)
				cube([width, rod_height, rod_thick]);

			//extruder
			translate([extruder_xpos, 0, 0]) color(printer_color) {
				translate([0,extruder_ypos+rod_height/2, 0])
					translate([-extruder_width/2,-extruder_height/2,-extruder_thick/2])
					cube([extruder_width,extruder_height,extruder_thick]);

				//nozzle
				translate([0,extruder_ypos-extruder_height/2-nozzle_height/4,0])
				rotate([90,0,0]) {
					cylinder(h = nozzle_height/2, r1 = nozzle_dia, r2 = nozzle_dia/4);
					translate([0,0,-nozzle_height/2])
						cylinder(h = nozzle_height/2, r = nozzle_dia);
				}
			}

			//Build Plate
			translate([-build_plate_width/2,-0.2,-thickness/2]) color(printer_color){
				cube([build_plate_width,build_plate_height,thickness*.9]);
			}

			//hanging hole
			if(enable_hole == 1) {
				translate([0,height+round_dia/2-hanging_hole_size/10,-thickness/2])
				color(plate_color) difference() {
					cylinder(h = thickness, r=hanging_hole_size);

					translate([-hanging_hole_size,-hanging_hole_size, -thickness/2])
						cube([hanging_hole_size*2,hanging_hole_size,thickness*2]);

					translate([0,hanging_hole_size/3,-thickness/2])
					cylinder(h = thickness*2, r=hanging_hole_size/4);
				}
			}

			//style
			if(style == 1) { //single side
				translate([-(width)/2, 0, -thickness/2]) color(plate_color)
					cube([width,height,thickness/4]);
			}

			//base
			if(base_style == 1 ) {
				translate([-width/2-round_dia/2,-round_dia,-thickness/2]) color(plate_color) {
					cube([width+round_dia,round_dia,thickness]);
				}
				translate([-width/2-round_dia/2,-round_dia/2,-thickness/2]) color(plate_color) {
					cube([round_dia/2,round_dia,thickness]);
				}
				translate([width/2,-round_dia/2,-thickness/2]) color(plate_color) {
					cube([round_dia/2,round_dia,thickness]);
				}
			}

			if(base_style == 2 ) {
				difference() {
					union() {
						translate([-width/2-round_dia/2,-round_dia,-thickness/2]) color(plate_color) {
							cube([width+round_dia,round_dia,thickness]);
						}
						translate([-width/2-round_dia/2,-round_dia/2,-thickness/2]) color(plate_color) {
							cube([round_dia/2,round_dia,thickness]);
						}
						translate([width/2,-round_dia/2,-thickness/2]) color(plate_color) {
							cube([round_dia/2,round_dia,thickness]);
						}
					}

					translate([-width/2+thickness,-round_dia-round_dia/2-round_dia/4,-thickness])
						cube([width-thickness*2,round_dia,thickness*2]);
				}
			}
		}
		text();
	}
}

//text
if(output_style == 0 || output_style == 2) {
	text();
}

}

module text() {
	difference() {
		union() {
			scale(text_scale)
				translate([-len(indicies)*text_font[0][0]/2,text_font[0][1]/2+.5-.05, -3])
				{
					for(i=[0:(len(indicies)-1)] )
						translate([ i*text_font[0][0], -text_font[0][1]/2 ,1])
						{
							//color(text_color)
								linear_extrude(height=4) polygon(points=text_font[2][indicies[i]][6][0],paths=text_font[2][indicies[i]][6][1]);
						}
				}
		}

		translate([extruder_xpos+nozzle_resolution/4,extruder_ypos-extruder_height/2-nozzle_height+rod_height/2-nozzle_resolution,-thickness])
			cube([width,height,thickness*2]);
		translate([-width+extruder_xpos+nozzle_resolution/4,extruder_ypos-extruder_height/2-nozzle_height+rod_height/2,-thickness])
			cube([width,height,thickness*2]);
	}
}
```


[User]
Okay, I'm trying to design a custom bobbin for winding wire, and I need some help creating the code. I've got a basic design working, but I'd like to add features for easier and more precise winding.

Here's what I have so far (and I'm attaching the code I wrote, `bobina_custumizer.scad`):

```
//////////////DICHIARAZIONI///////////////////////

r=44;//minimo 8mm massimo 100mm
depth=24;//spessore bobina
height=24;//altezza bobina
distance=r-1;
distance2=r+depth+3;

///////////////////////////////////////////////////
$fn=80;

module A()//scanalature
{
if (r>15){ hull(){
	translate([0, distance,0])cylinder(height/2+3,3,3);
	translate([0,distance2+depth,0])cylinder(height/2+3,3,3);
					}}
else { hull(){
	translate([0, distance,0])cylinder(height/2+3,2,2);
	translate([0,distance2,0])cylinder(height/2+3,2,2);
					}}
}

module incastro()//giunzione
		{
		translate([1.5,-1.5,height/2+2])rotate([90,0,45])cylinder(r,1.5,1.5);
		translate([1.5,1.5,height/2+2])rotate([90,0,135])cylinder(r,1.5,1.5);
translate([-1.5,-1.5,height/2+2])rotate([90,0,-45])cylinder(r,1.5,1.5);
translate([-1.5,1.5,height/2+2])rotate([90,0,-135])cylinder(r,1.5,1.5);
		}
module coil()
{
difference()
	{
	union()
		{
		cylinder(2,r+depth+2,r+depth); //disco maggiore
		cylinder(height/2+2,r+2,r+2); //disco minore
		}
		cylinder(height/2+3,3,3); //foro centrale
		incastro();
		rotate([0,0,0])		A();
		rotate([0,0,90])		A();
		rotate([0,0,180])	A();
		rotate([0,0,270])	A();
}
}

coil();
translate([r*2+depth*2+8,0,0])coil();
incastro();

```
The code creates a basic bobbin with some grooves (module `A`) and interlocking pieces (module `incastro`). The `coil` module creates one bobbin, and then the code places a second copy.

Here's what I'd like to add, and for which I need a parametric OpenSCAD file:

1.  **Wire Guide Channels:** I need to add channels or slots along the side of the bobbin to guide the wire as it's being wound. I'd like to be able to specify the number of these channels, their depth, and their width. They should run parallel to the axis of rotation. It'd be good if they are rounded at the bottom of the channel so that the wire doesn't form a sharp bend.

2.  **Layering:** I want to be able to control the number of layers the guide channels span. For example, I may not want a channel going the full depth of the bobbin, only some fraction, this fraction should be a parameter. If the parameter is 1, then the channel goes the full depth. A parameter of 0.5 would mean that the channel goes half the depth.

3.  **Starting Point for Winding:** It would be helpful to have a way to mark or define a precise starting point for winding the wire, possibly through a small notch or indentation on the outer edge of the bobbin or on the side, either on the upper part or the lower part of the bobbin. I’m thinking this would be something like a small rectangular cutout or a shallow ramp.

4.  **Bobbin Assembly:** I'd like to maintain the modular design where I can have the two halves of the bobbin. And the `incastro()` system.

5. **Parameterization:**
    *   `r`: Radius of the inner core of the bobbin (same as original code, minimum 8mm, maximum 100mm).
    *   `depth`: Thickness of the bobbin (same as the original code).
    *   `height`: Height/length of the bobbin (same as the original code).
    *   `channel_count`: Number of wire guide channels around the perimeter.
    *   `channel_depth`: Depth of the guide channels.
    *   `channel_width`: Width of the guide channels.
		* `channel_fraction`: Fraction of the height to span for channel. (0 - 1).
    *   `start_mark_type`: Type of start mark, options might be "notch", "ramp", or "none."
    *  `start_mark_size`: Size of the starting mark.

I'd prefer to use standard OpenSCAD primitives where possible, but if needed, it's acceptable to include functions from the `MCAD` library. Please keep the code clean and well-commented.

Can you help me create this parametric design?

[Assistant]
bobina_custumizer.scad:
```
//////////////DICHIARAZIONI///////////////////////

r=44;//minimo 8mm massimo 100mm
depth=24;//spessore bobina
height=24;//altezza bobina
distance=r-1;
distance2=r+depth+3;

///////////////////////////////////////////////////
$fn=80;

module A()//scanalature
{
if (r>15){ hull(){
	translate([0, distance,0])cylinder(height/2+3,3,3);
	translate([0,distance2+depth,0])cylinder(height/2+3,3,3);
					}}
else { hull(){
	translate([0, distance,0])cylinder(height/2+3,2,2);
	translate([0,distance2,0])cylinder(height/2+3,2,2);
					}}
}

module incastro()//giunzione
		{
		translate([1.5,-1.5,height/2+2])rotate([90,0,45])cylinder(r,1.5,1.5);
		translate([1.5,1.5,height/2+2])rotate([90,0,135])cylinder(r,1.5,1.5);
translate([-1.5,-1.5,height/2+2])rotate([90,0,-45])cylinder(r,1.5,1.5);
translate([-1.5,1.5,height/2+2])rotate([90,0,-135])cylinder(r,1.5,1.5);
		}
module coil()
{
difference()
	{
	union()
		{
		cylinder(2,r+depth+2,r+depth); //disco maggiore
		cylinder(height/2+2,r+2,r+2); //disco minore
		}
		cylinder(height/2+3,3,3); //foro centrale
		incastro();
		rotate([0,0,0])		A();
		rotate([0,0,90])		A();
		rotate([0,0,180])	A();
		rotate([0,0,270])	A();
}
}

coil();
translate([r*2+depth*2+8,0,0])coil();
incastro();

```


[User]
Okay, I'd like to design a sphere with cylindrical holes going through it. I need an OpenSCAD file that can generate this.

Here are the specifics:

*   **Core Shape:** The base object is a sphere.
*   **Holes:** There are three cylindrical holes going completely through the sphere. These holes are perpendicular to each other and all intersect at the center of the sphere. Essentially, imagine a sphere with holes along the X, Y, and Z axes.
*   **Parametric Design:** I need to be able to adjust the following parameters:
    *   `sphere_radius`: The radius of the main sphere.
    *   `hole_radius`: The radius of the cylindrical holes.

I'd like to be able to change these two values easily in OpenSCAD's customizer. Please provide the complete OpenSCAD code that does this. I do not need any libraries in addition to the default library.

[Assistant]
holesphere.scad:
```
// Radius of big sphere
sphere_radius = 10; // [2:100]

// Radius of the holes in the sphere
hole_radius = 5; // [1:100]

difference(){
 translate([sphere_radius,0,sphere_radius])
  sphere(sphere_radius);
 union(){
  translate([sphere_radius,0,0])
   cylinder(2*sphere_radius,hole_radius,hole_radius);
  translate([sphere_radius,sphere_radius,sphere_radius]) rotate([90,0,0])
   cylinder(2*sphere_radius,hole_radius,hole_radius);
  translate([0,0,sphere_radius]) rotate([0,90,0])
   cylinder(2*sphere_radius,hole_radius,hole_radius);
 }
}

```


[User]
Okay, I'm trying to design a universal car mount system using OpenSCAD, and I've already got a good start with the `mount_bracket.scad` file I've been working on (I've included it below).  The idea is that I want to be able to easily adapt the bracket to different devices by changing a few parameters, like `device_height`, `device_depth`, and `hook_length`. The bracket itself attaches to a bar, which then attaches to a car mount plate (like the ones that sell for a few dollars with suction cups).

I need to be able to create two types of bars: a standard one that will fit into the purchased mount plates (which have a sort of T-shaped slot), and a simple bar with an M6 screw hole, so I can use a mount that uses a standard M6 screw. Both bar types should work with the same bracket. I need this to be parametric, so the bar lengths and thicknesses can be adjusted.

Specifically, I need these parts:

1.  **The Bracket:** I've already made good progress with this, and I've included it as `mount_bracket.scad` below. This bracket needs to be fully parametric, and should attach to either of the two bar designs. The critical parameters for the bracket are:
    *   `device_height`: The height of the device where the bracket grips it.
    *   `device_depth`: The depth of the device near the edge.
    *   `height`: The height of the bracket (to fit a standard bar latch slot).
    *   `hook_length`: The length of the front hook that holds the device.
    *   `thickness`: Thickness of material used in the bracket.
    *   I also need to make sure the connector at the bottom matches the dimensions of the two types of bars described below. It's currently set using `fixation_outer_width`, `fixation_inner_width`, `fixation_inner_depth`, and `fixation_outer_depth` in my current code.

2. **Standard Bar:** This bar needs to have a T-shaped profile to fit into the standard car mount plates that have a T-shaped slot. The dimensions of this T-shape need to be adjustable. I need parameters for:
    *   `standard_bar_length`: The length of the standard bar.
    *   `standard_bar_width`: The width of the bar itself (not the T-slot).
    *   `standard_bar_height`: The height of the bar itself (not the T-slot).
    *   `standard_t_width`: The overall width of the "T" shape
    *   `standard_t_height`: The height of the base of the "T" shape (i.e. the part that slides into the mount).
    *   `standard_t_depth`: The depth of the "T" shape.
    *   `standard_bar_thickness`: The thickness of the material

3.  **Screw Bar:** A simpler bar with an M6 screw hole in the center.  It should still be compatible with the brackets. The parameters for this bar should be:
    *   `screw_bar_length`: The length of the screw bar.
    *   `screw_bar_width`: The width of the screw bar.
    *   `screw_bar_height`: The height/thickness of the screw bar.
    *   `screw_hole_diameter`: The diameter of the screw hole (will likely be 6.5 mm for a typical M6 screw)

Both bars should have the necessary connecting element to mate with the brackets produced by `mount_bracket.scad`.

I think it would be good to be able to toggle between these using a selector/variable at the start. I would like the bars to be independent modules. I don't need any fancy functions, just basic `cube`, `cylinder`, `translate`, `difference`, `union`, `linear_extrude`, and `rotate` functionalities.

I want to keep the code modular and clear, so it is easy to adjust, and I'd prefer not to include external libraries. Can you help me design an OpenSCAD file that includes all of this?

```openscad
// Values are for TomTom Start 60

// Height of device, measured where bracket will be placed.
device_height=101.5;

// Depth of device; measured near border of device.
device_depth=9;

// Bracket height, must correspond to latch space at bar. 10 is a reasonable value.
height=10;

// Hook in front of the device.
hook_length=7;

/* [Hidden] */
// Values for Xperia Active
// device_height=55;
// device_depth=16;
// hook_length=7;

// no changes below this line
// --------------------------
// device independent, must fit connector
thickness=2;

// convert to object internal values
width=device_height-2*thickness;
depth=device_depth-2*thickness;

module arm () {
// main beam
cube([width/2, thickness, height]);

// first corner

difference() {
  difference() {
    translate([width/2,-thickness,0])cylinder(r=2*thickness, h=height, $fn=60);
    translate([width/2,-thickness,0])cylinder(r=thickness, h=height, $fn=60);
  }
  union() {
    translate([width/2-2*thickness,-3*thickness,0])cube([2*thickness,3*thickness, height]);
    translate([width/2,-3*thickness,0])cube([2*thickness,2*thickness, height]);
  }
};

// short beam
translate([width/2+thickness,-thickness-depth,0])cube([thickness,depth,height]);

// second corner
difference() {
  difference() {
    translate([width/2,-thickness-depth,0])cylinder(r=2*thickness, h=height, $fn=60);
    translate([width/2,-thickness-depth,0])cylinder(r=thickness, h=height, $fn=60);
  }
  union() {
    translate([width/2-2*thickness,-3*thickness-depth,0])cube([2*thickness,4*thickness, height]);
    translate([width/2-thickness,-thickness-depth,0])cube([2*thickness,2*thickness, height]);
  }
};

// make end hook and move in place
translate([width/2-hook_length,-thickness*2-depth,0])
  linear_extrude(height=height)polygon(points=[[0,0],[hook_length,0],[hook_length,-thickness],[0,-thickness/2]]);

// do not change, this is the connector part
fixation_outer_width=37;
fixation_inner_width=20.4;
fixation_inner_depth=6.1;
fixation_outer_depth=fixation_inner_depth+2;

difference () {
 difference () {
  difference () {
    cube([fixation_outer_width/2, fixation_outer_depth, height]);
    cube([fixation_inner_width/2, fixation_inner_depth, height]);
   }
   translate([fixation_outer_width/2,thickness+2,0])cylinder(r=2, h=height, $fn=60);
 }
 translate([fixation_outer_width/2-sqrt(2),sqrt(2)*2,0])rotate(45)cube([10,10,height]);
};
};
// end module arm

arm();
mirror() arm();
```

[Assistant]
mount_bracket.scad:
```
// Values are for TomTom Start 60

// Height of device, measured where bracket will be placed.
device_height=101.5;

// Depth of device; measured near border of device.
device_depth=9;

// Bracket height, must correspond to latch space at bar. 10 is a reasonable value.
height=10;

// Hook in front of the device.
hook_length=7;

/* [Hidden] */
// Values for Xperia Active
// device_height=55;
// device_depth=16;
// hook_length=7;

// no changes below this line
// --------------------------
// device independent, must fit connector
thickness=2;

// convert to object internal values
width=device_height-2*thickness;
depth=device_depth-2*thickness;

module arm () {
// main beam
cube([width/2, thickness, height]);

// first corner

difference() {
  difference() {
    translate([width/2,-thickness,0])cylinder(r=2*thickness, h=height, $fn=60);
    translate([width/2,-thickness,0])cylinder(r=thickness, h=height, $fn=60);
  }
  union() {
    translate([width/2-2*thickness,-3*thickness,0])cube([2*thickness,3*thickness, height]);
    translate([width/2,-3*thickness,0])cube([2*thickness,2*thickness, height]);
  }
};

// short beam
translate([width/2+thickness,-thickness-depth,0])cube([thickness,depth,height]);

// second corner
difference() {
  difference() {
    translate([width/2,-thickness-depth,0])cylinder(r=2*thickness, h=height, $fn=60);
    translate([width/2,-thickness-depth,0])cylinder(r=thickness, h=height, $fn=60);
  }
  union() {
    translate([width/2-2*thickness,-3*thickness-depth,0])cube([2*thickness,4*thickness, height]);
    translate([width/2-thickness,-thickness-depth,0])cube([2*thickness,2*thickness, height]);
  }
};

// make end hook and move in place
translate([width/2-hook_length,-thickness*2-depth,0])
  linear_extrude(height=height)polygon(points=[[0,0],[hook_length,0],[hook_length,-thickness],[0,-thickness/2]]);

// do not change, this is the connector part
fixation_outer_width=37;
fixation_inner_width=20.4;
fixation_inner_depth=6.1;
fixation_outer_depth=fixation_inner_depth+2;

difference () {
 difference () {
  difference () {
    cube([fixation_outer_width/2, fixation_outer_depth, height]);
    cube([fixation_inner_width/2, fixation_inner_depth, height]);
   }
   translate([fixation_outer_width/2,thickness+2,0])cylinder(r=2, h=height, $fn=60);
 }
 translate([fixation_outer_width/2-sqrt(2),sqrt(2)*2,0])rotate(45)cube([10,10,height]);
};
};
// end module arm

arm();
mirror() arm();
```