[User]
I'd like to create a parametric design for a bit storage solution, like the one described in this article: https://wayofwood.com/3d-printed-bit-storage-ideas/ and shown in this video: https://youtu.be/jnaL57ZjVSQ

Essentially, it's a cylindrical container with a threaded outer surface, and then a series of hexagonal bit holders arranged in rings around the circumference. The container is designed so that the outer thread mates with a cap that has an internal thread.

Here are the parameters I would like to be able to adjust:

*   **Number of rings**: This controls how many concentric rings of bit holders there are.
*   **Bit holder radius**: The radial distance from the center of the bit holder to the origin.
*   **Number of bit holders per ring**: A user should be able to specify a number of bits per ring
*   **Bit holder height**: How tall the bit holders are (all holders the same height).
*   **Hex size**: Size of the hex for the bit holders, and therefore the size of the bit that can be inserted.
*   **Thread diameter**: The major diameter of the outer thread.
*  **Thread height**: The height of the outer thread.
*   **Thread pitch**: The distance between adjacent threads.
*  **Thread wiggle room**: A parameter controlling the difference in diameter between the male and female threads (i.e., clearance between the thread on the body and the cap).
*   **Container height**: The overall height of the cylindrical container.
*   **Cap height**: The height of the cap.
*  **Cap diameter**: The diameter of the cap.
* **Cap thread height**: The height of the internal thread on the cap.

The bit holders should be created using a simple 2D extrusion of a hexagon. The threads should be standard ISO metric threads. I would also like some control over the number of segments used to represent the threads so I can adjust quality/performance. The bit holders should be offset a bit in the Z axis (so that they don't rest flush with the bottom of the container).

I'd like to generate a couple of files -- one for the body, and another for the cap.

Let me know if you have any questions.

[Assistant]
bitsafe.scad:
```
// ISO Metric Thread Implementation
// Trevor Moseley
// 20/04/2014

// For thread dimensions see
//   http://en.wikipedia.org/wiki/File:ISO_and_UTS_Thread_Dimensions.svg

$fn=30*1;
WrenchSizes=0*1;	// =0= Rolson sizes, =1=Fairbury sizes

//--demo functions--------------------------------------------------------------

//hex_bolt(10,16);						// make an M10 x 16 ISO bolt
//hex_nut(10);							// make an M10 ISO nut
//hex_bolt(8,16);						// make an M8 x 16 ISO bolt
//hex_nut(8);							// make an M8 ISO nut
//hex_bolt(6,12);						// make an M6 x 12 ISO bolt
//hex_nut(6);							// make an M6 ISO nut
//thread_out(8,16);					// make an M8 x 16 ISO thread
//thread_out_centre(8,16);				// make a centre for an M8 x 16 ISO thread
//thread_out_pitch(80,10,2.0);			// make an M8 x 16 thread with 1 mm pitch
//thread_out_centre_pitch(8,16,0.5);	// make the centre for an M8 x 16 thread with 1 mm pitch
// thread_in(8,10);						// make an M8 x 10 ISO thread
//thread_in_ring(8,10,2);				// make a ring to enclose an M8 x 10 ISO thread with thickness 2 mm
//thread_in_pitch(8,10,1.0);			// make an M8 x 10 thread with 1mm pitch

//How many rings of bits do you want to have?
rings = 2;
diameter = 2* ( 9 + 9*rings ) - 4.5;
// How tight should be the fit? (smaller = tighter)
wiggle = 0.2;

difference() {
	union() {
		cylinder(d=diameter,h=10);
		cylinder(d=diameter+9,h=2);
		thread_out_pitch(diameter+2,10,2.0);
	}
	bit(0,0);
	for (i=[1:rings]) {
		radius = 9*i;
		count = floor( (2*3.14*radius) / 9 );
		echo(count);
		for (j=[1:count]) {
			bit(cos(j*360/count)*radius, sin(j*360/count)*radius);
		}
	}
}

translate([diameter*1.5,0,0])
	union () {
		difference() {
			cylinder(d=diameter+4,h=30);
			cylinder(d=diameter+2+wiggle,h=31);
		}
		translate([0, 0, 20]) thread_in_pitch(diameter+2+wiggle,10,2.0);
		cylinder(d=diameter+6,h=2);

	}

module bit(x,y) {
	translate([0,0,4+2]) linear_extrude(height=8.1,center=true) hexagon(3.4,x,y);
}

module hexagon(r,x,y){
polygon(points=[[(r+x),(r*(tan(30)))+y],
                [x,(r*(2/sqrt(3)))+y],
                [-r+x,(r*(tan(30)))+y],
                [-r+x,-(r*(tan(30)))+y],
                [x,-(r*(2/sqrt(3)))+y],
                [r+x,-(r*(tan(30)))+y]]);

 }

//--pitch-----------------------------------------------------------------------
// function for ISO coarse thread pitch (these are specified by ISO)
function get_coarse_pitch(dia) = lookup(dia, [
[1,0.25],[1.2,0.25],[1.4,0.3],[1.6,0.35],[1.8,0.35],[2,0.4],[2.5,0.45],[3,0.5],[3.5,0.6],[4,0.7],[5,0.8],[6,1],[7,1],[8,1.25],[10,1.5],[12,1.75],[14,2],[16,2],[18,2.5],[20,2.5],[22,2.5],[24,3],[27,3],[30,3.5],[33,3.5],[36,4],[39,4],[42,4.5],[45,4.5],[48,5],[52,5],[56,5.5],[60,5.5],[64,6],[78,5]]);

//--nut dims--------------------------------------------------------------------
// these are NOT specified by ISO
// support is provided for Rolson or Fairbury sizes, see WrenchSizes above

// function for Rolson hex nut diameter from thread size
function rolson_hex_nut_dia(dia) = lookup(dia, [
[3,6.4],[4,8.1],[5,9.2],[6,11.5],[8,16.0],[10,19.6],[12,22.1],[16,27.7],[20,34.6],[24,41.6],[30,53.1],[36,63.5]]);
// function for Rolson hex nut height from thread size
function rolson_hex_nut_hi(dia) = lookup(dia, [
[3,2.4],[4,3.2],[5,4],[6,3],[8,5],[10,5],[12,10],[16,13],[20,16],[24,19],[30,24],[36,29]]);

// function for Fairbury hex nut diameter from thread size
function fairbury_hex_nut_dia(dia) = lookup(dia, [
[3,6.0],[4,7.7],[5,8.8],[6,11.0],[8,14.4],[10,17.8],[12,20.0],[16,26.8],[20,33.0],[24,40.0],[30,50.9],[36,60.8]]);
// function for Fairbury hex nut height from thread size
function fairbury_hex_nut_hi(dia) = lookup(dia, [
[3,2.2],[4,3.0],[5,4.5],[6,5.0],[8,6.5],[10,8.1],[12,10.4],[16,14.2],[20,17],[24,20.3],[30,24.4],[36,29.5]]);

//--bolt dims-------------------------------------------------------------------
// these are NOT specified by ISO
// support is provided for Rolson or Fairbury sizes, see WrenchSizes above

// function for Rolson hex bolt head diameter from thread size
function rolson_hex_bolt_dia(dia) = lookup(dia, [
[3,6.4],[4,8.1],[5,9.2],[6,11.5],[8,14.0],[10,16],[12,22.1],[16,27.7],[20,34.6],[24,41.6],[30,53.1],[36,63.5]]);
// function for Rolson hex bolt head height from thread size
function rolson_hex_bolt_hi(dia) = lookup(dia, [
[3,2.4],[4,3.2],[5,4],[6,3.5],[8,4.5],[10,5],[12,10],[16,13],[20,16],[24,19],[30,24],[36,29]]);

// function for Fairbury hex bolt head diameter from thread size
function fairbury_hex_bolt_dia(dia) = lookup(dia, [
[3,6.4],[4,8.1],[5,8.8],[6,11.1],[8,14.4],[10,17.8],[12,20.1],[16,26.8],[20,33.0],[24,39.6],[30,50.9],[36,60.8]]);
// function for Fairbury hex bolt head height from thread size
function fairbury_hex_bolt_hi(dia) = lookup(dia, [
[3,2.4],[4,3.2],[5,3.4],[6,3.9],[8,5.1],[10,6.2],[12,7.3],[16,9.7],[20,12.2],[24,14.6],[30,17.9],[36,21.7]]);

//--top level modules-----------------------------------------------------------

module hex_bolt(dia,hi)
// make an ISO bolt
//  dia=diameter, 6=M6 etc.
//  hi=length of threaded part of bolt
{
	if (WrenchSizes==0)	rolson_hex_bolt(dia,hi);
	else					fairbury_hex_bolt(dia,hi);
}

module hex_nut(dia,hi)
// make an ISO nut
//  dia=diameter, 6=M6 etc.
{
	if (WrenchSizes==0)	rolson_hex_nut(dia);
	else					fairbury_hex_nut(dia);
}

module thread_out(dia,hi,thr=$fn)
// make an outside ISO thread (as used on a bolt)
//  dia=diameter, 6=M6 etc
//  hi=height, 10=make a 10mm long thread
//  thr=thread quality, 10=make a thread with 10 segments per turn
{
	p = get_coarse_pitch(dia);
	thread_out_pitch(dia,hi,p,thr);
}

module thread_in(dia,hi,thr=$fn)
// make an inside thread (as used on a nut)
//  dia = diameter, 6=M6 etc
//  hi = height, 10=make a 10mm long thread
//  thr = thread quality, 10=make a thread with 10 segments per turn
{
	p = get_coarse_pitch(dia);
	thread_in_pitch(dia,hi,p,thr);
}

module thread_out_pitch(dia,hi,p,thr=$fn)
// make an outside thread (as used on a bolt) with supplied pitch
//  dia=diameter, 6=M6 etc
//  hi=height, 10=make a 10mm long thread
//  p=pitch
//  thr=thread quality, 10=make a thread with 10 segments per turn
{
	h=(cos(30)*p)/8;
	Rmin=(dia/2)-(5*h);	// as wiki Dmin
	s=360/thr;				// length of segment in degrees
	t1=(hi-p)/p;			// number of full turns
	r=t1%1.0;				// length remaining (not full turn)
	t=t1-r;					// integer number of full turns
	n=r/(p/thr);			// number of segments for remainder
	// do full turns
	for(tn=[0:t-1])
		translate([0,0,tn*p])	th_out_turn(dia,p,thr);
	// do remainder
	for(sg=[0:n])
		th_out_pt(Rmin,p,s,sg+(t*thr),thr,h,p/thr);
}

module thread_in_pitch(dia,hi,p,thr=$fn)
// make an inside thread (as used on a nut)
//  dia = diameter, 6=M6 etc
//  hi = height, 10=make a 10mm long thread
//  p=pitch
//  thr = thread quality, 10=make a thread with 10 segments per turn
{
	h=(cos(30)*p)/8;
	Rmin=(dia/2)-(5*h);	// as wiki Dmin
	s=360/thr;				// length of segment in degrees
	t1=(hi-p)/p;			// number of full turns
	r=t1%1.0;				// length remaining (not full turn)
	t=t1-r;					// integer number of turns
	n=r/(p/thr);			// number of segments for remainder
	for(tn=[0:t-1])
		translate([0,0,tn*p])	th_in_turn(dia,p,thr);
	for(sg=[0:n])
		th_in_pt(Rmin+0.1,p,s,sg+(t*thr),thr,h,p/thr);
}

module thread_out_centre(dia,hi)
{
	p = get_coarse_pitch(dia);
	thread_out_centre_pitch(dia,hi,p);
}

module thread_out_centre_pitch(dia,hi,p)
{
	h = (cos(30)*p)/8;
	Rmin = (dia/2) - (5*h);	// as wiki Dmin
	cylinder(r = Rmin, h = hi);
}

module thread_in_ring(dia,hi,thk)
{
	difference()
	{
		cylinder(r = (dia/2)+0.5,h = hi);
		translate([0,0,-1]) cylinder(r = (dia/2)+0.1, h = hi+thk);
	}
}

//--low level modules-----------------------------------------------------------

module rolson_hex_bolt(dia,hi)
// make an ISO bolt with Rolson wrench sizes
//  dia=diameter, 6=M6 etc.
//  hi=length of threaded part of bolt
{
	hhi = rolson_hex_bolt_hi(dia);
	cylinder(r = rolson_hex_bolt_dia(dia)/2,h = hhi, $fn=6);
	translate([0,0,hhi-0.1])	thread_out(dia,hi+0.1);
	translate([0,0,hhi-0.1])	thread_out_centre(dia,hi+0.1);
}

module fairbury_hex_bolt(dia,hi)
// make an ISO bolt with Fairbury wrench sizes
//  dia=diameter, 6=M6 etc.
//  hi=length of threaded part of bolt
{
	hhi = fairbury_hex_bolt_hi(dia);
	cylinder(r = fairbury_hex_bolt_dia(dia)/2,h = hhi, $fn=6);
	translate([0,0,hhi-0.1])	thread_out(dia,hi+0.1);
	translate([0,0,hhi-0.1])	thread_out_centre(dia,hi+0.1);
}

module rolson_hex_nut(dia)
// make an ISO nut with Rolson wrench sizes
//  dia=diameter, 6=M6 etc.
{
	hi = rolson_hex_nut_hi(dia);
	difference()
	{
		cylinder(r = rolson_hex_nut_dia(dia)/2,h = hi, $fn=6);
		translate([0,0,-0.1])	cylinder(r = dia/2+0.1, h =hi + 0.2);
	}
	translate([0,0,0.1])	thread_in(dia,hi-0.2);
}

module fairbury_hex_nut(dia)
// make an ISO nut with Fairbury wrench sizes
//  dia=diameter, 6=M6 etc.
{
	hi = fairbury_hex_nut_hi(dia);
	difference()
	{
		cylinder(r = fairbury_hex_nut_dia(dia)/2,h = hi, $fn=6);
		translate([0,0,-0.1])	cylinder(r = dia/2+0.1, h =hi + 0.2);
	}
	translate([0,0,0.1])	thread_in(dia,hi-0.2);
}

module th_out_turn(dia,p,thr=$fn)
// make a single turn of an outside thread
//  dia=diameter, 6=M6 etc
//  p=pitch
//  thr=thread quality, 10=make a thread with 10 segments per turn
{
	h = (cos(30)*p)/8;
	Rmin = (dia/2) - (5*h);	// as wiki Dmin
	s = 360/thr;
	for(sg=[0:thr-1])
		th_out_pt(Rmin,p,s,sg,thr,h,p/thr);
}

module th_out_pt(rt,p,s,sg,thr,h,sh)
// make a part of an outside thread (single segment)
//  rt = radius of thread (nearest centre)
//  p = pitch
//  s = segment length (degrees)
//  sg = segment number
//  thr = segments in circumference
//  h = ISO h of thread / 8
//  sh = segment height (z)
{
	as = (sg % thr) * s;			// angle to start of seg
	ae = as + s;		// angle to end of seg (with overlap)
	z = sh*sg;
	//pp = p/2;
	//   1,4
	//   |\
	//   | \  2,5
 	//   | /
	//   |/
	//   0,3
	//  view from front (x & z) extruded in y by sg
	//
	//echo(str("as=",as,", ae=",ae," z=",z));
	polyhedron(
		points = [
			[cos(as)*rt,sin(as)*rt,z],								// 0
			[cos(as)*rt,sin(as)*rt,z+(3/4*p)],						// 1
			[cos(as)*(rt+(5*h)),sin(as)*(rt+(5*h)),z+(3/8*p)],		// 2
			[cos(ae)*rt,sin(ae)*rt,z+sh],							// 3
			[cos(ae)*rt,sin(ae)*rt,z+(3/4*p)+sh],					// 4
			[cos(ae)*(rt+(5*h)),sin(ae)*(rt+(5*h)),z+sh+(3/8*p)]],	// 5
		faces = [
			[0,1,2],			// near face
			[3,5,4],			// far face
			[0,3,4],[0,4,1],	// left face
			[0,5,3],[0,2,5],	// bottom face
			[1,4,5],[1,5,2]]);	// top face
}

module th_in_turn(dia,p,thr=$fn)
// make an single turn of an inside thread
//  dia = diameter, 6=M6 etc
//  p=pitch
//  thr = thread quality, 10=make a thread with 10 segments per turn
{
	h = (cos(30)*p)/8;
	Rmin = (dia/2) - (5*h);	// as wiki Dmin
	s = 360/thr;
	for(sg=[0:thr-1])
		th_in_pt(Rmin+0.1,p,s,sg,thr,h,p/thr);
}

module th_in_pt(rt,p,s,sg,thr,h,sh)
// make a part of an inside thread (single segment)
//  rt = radius of thread (nearest centre)
//  p = pitch
//  s = segment length (degrees)
//  sg = segment number
//  thr = segments in circumference
//  h = ISO h of thread / 8
//  sh = segment height (z)
{
	as = ((sg % thr) * s - 180);	// angle to start of seg
	ae = as + s;		// angle to end of seg (with overlap)
	z = sh*sg;
	pp = p/2;
	//         2,5
	//          /|
	//     1,4 / |
 	//         \ |
	//          \|
	//         0,3
	//  view from front (x & z) extruded in y by sg
	//
	polyhedron(
		points = [
			[cos(as)*(rt+(5*h)),sin(as)*(rt+(5*h)),z],				//0
			[cos(as)*rt,sin(as)*rt,z+(3/8*p)],						//1
			[cos(as)*(rt+(5*h)),sin(as)*(rt+(5*h)),z+(3/4*p)],		//2
			[cos(ae)*(rt+(5*h)),sin(ae)*(rt+(5*h)),z+sh],			//3
			[cos(ae)*rt,sin(ae)*rt,z+(3/8*p)+sh],					//4
			[cos(ae)*(rt+(5*h)),sin(ae)*(rt+(5*h)),z+(3/4*p)+sh]],	//5
		faces = [
			[0,1,2],			// near face
			[3,5,4],			// far face
			[0,3,4],[0,4,1],	// left face
			[0,5,3],[0,2,5],	// bottom face
			[1,4,5],[1,5,2]]);	// top face
}

```


[User]
Okay, I'm looking to generate some snap-fit rings, and I've seen a few designs that use overlapping hooks. I'd like to create a parametric OpenSCAD design that allows me to customize the ring's dimensions and shape.

Specifically, I need the following features:

1.  **Ring Shape:** The design should let me choose between a square or round cross-section for the ring.
2.  **Ring Dimensions:**
    *   I need to be able to specify the ring's thickness.
    *   I need to specify the ring's outer diameter.
3.  **Hook Design:** The ring should have two overlapping hooks that snap together. I'd like an adjustable parameter to control the gap (tolerance) between the hooks.
4.  **Parametric Control:**  I'm looking for these parameters to be adjustable in the OpenSCAD customizer interface, so I need the correct syntax for that.
5.  **Printability:** The design should be optimized for 3D printing, and it would be really nice if the design could automatically flip the ring for printing (bottom hook on the build plate) and then re-zero for the final view.
6. **Angle and Offset Control:** The code should include separate parameters for the bottom hook angle and horizontal offset relative to the top hook.
7. **Preview:**  It's very important that I can view the model and confirm that there's still a gap between the hooks *before* I print anything.

I'm not planning to use any specific libraries, I'd like the design to be self-contained in one file.

[Assistant]
Generate_Locking_Snap_Rings_Square_or_Circular.scad:
```
// Produces a ring with overlapping hooks that are held together with pressure.
// Nice inexpensive way to hold something together.

// ============ Support Notes ===============
// I support off the plate which recreates a small support at the bottom of the top hook.
// v1.1 12/2021
    //flipped over the ring for print so you don't have to
    //Added adjustments for bottom hook angle and offset for better alignment
    //added sliders to customizer so you can more rapidly move things around

// =========== Material Notes ===================
// It works well with PLA as it is rigid.
// I have been printing at 20% fill.  Remember if you go too low on fill, PLA can take on its new shape with time loosing its spring.
// For PETG you may want to set your fill higher and/or use thicker ring.  I have not printed any yet.
// I have not tested other materials.

// ROUND vs SQUARE
// round will have more flex so add more fill to make it more firm
// you should brim the round so it does not leave the bed
// if you printer has issues with round edges.. use support or do the square which sits on the bed.

// ================== INSTRUCTIONS ====================
// To use Customizer select VIEW, Un-check "HIDE CUSTOMIZER" press F5 and set settings in customizer.
//  1) Set your ringthickness
//  2) set your Ring Diameter
//  3) Only change the hook tolerance if you have an issue or are printing thick rings of a small diameter
//  4) F5 to preview... check that the gap between the hooks is still there.  If for some reason it is goin you may have to increase bottonhookoffset_factor
//  I have typed in many random functional ring combinations and the formula's seam to accomodate them reasonablly well.
//  Hit + and save your ring profile for re-use.

// some conbimation notes:
// thickness = 3, dia = 32 required a 5mm hole (13/64 inch) for comfortable slip on.

// =========== How to run this code ================
// This is an openscad file.  The program is open source and available at https://www.openscad.org/downloads.html
// Press F5 to refresh
// OpensCAD program F6 to generate/render and then STL export
// Slice your STL in your slicer and print

//===================== Author ====================
//Initial version created by  AlwaysTinkering 5/2021  https://www.youtube.com/channel/UC27SvMnOzIKx8oxlgZc5AEQ   https://www.thingiverse.com/alwaystinkering/designs https://www.prusaprinters.org/social/116733-alwaystinkering/prints

//** NOTES **
// I added some ranges on the numbers so sliders appear in customizer
////[40:.5:250] means from 40 to 250 with an incremant of .5  Change as you desire.

//================= BASIC INPUT ATTRIBUTES ====================== customizer compliant
// Do you want the ring to be Square or Round
ringtype = "round";  //[square, round]

//Diameter or Thickness of the ring
ringthickness = 4; //[.5:.5:10]

//Ring Outer Diameter
ring_outer_diameter = 45.5; //[10:.5:200]

// ringthickness * this number will be added to the hook space.  Default is .05 and should work for most.
hooktoleranceratio = .05;

// ============ END OF BASIC ATTRIBUTES
//============================================================================
/* [Hidden] */

$fn=90; // samples to take in making the curves... lower number rougher edges.
ring_outer_radius = ring_outer_diameter / 2;

//test tip will appear in the center
//smallhalfring(-1, "top");

bottonhookoffset_factor = 2.95;     //this is how far to the left the bottom hook will be offset.  Keep in mind the further you offset the lower you go on the ring.  You may need to increase the hooktoleranceratio if you move down the ring since the angle of the cuts may be too far apart to line up well.  This is in extreme situations.  The default of 2.95 seams to work well.

bottom_offsetfactor = .87;  // the reduction of the ring to make the gap hits a lower point ont he circle.. this adjust the offset.abs

bottom_rotation_factor = 105; //this started at 90, but again because we are lower on the circle it needs to bemore.

bottomclip_dist_offcenterline = ring_outer_radius - sqrt( (ring_outer_radius * ring_outer_radius) - ( (ringthickness * bottonhookoffset_factor  )*  (ringthickness * bottonhookoffset_factor * bottom_offsetfactor  ) ) ) ; // .87 because the ring is lower at the separation.. and needs to be rotated for better alignment.

echo("bottomclip_dist_offcenterline= ", bottomclip_dist_offcenterline);

//flip it over for print and return to zero
translate([0,0, ringthickness])
rotate([180,0,0])

{
// top hook that prints off plate
translate([ring_outer_radius- ringthickness / 2, .5  ,- ringthickness /2])
rotate([90,0,90])
{
smallhalfring(-1, "top");
}

//+ ringthickness / 2 +
// bottom hook that prints on plate
//translate([ring_outer_radius+ 1.15, -ringthickness * 2.75 ,0])
//translate([ring_outer_radius - bottomclip_dist_offcenterline + ringthickness , -ringthickness * 2.85 ,0])

// the bottom flat hook in some combinations need the slot recut
// This is because I did not do the math to compensate for the cut into the circle in some diameter / thickness combinations creates a longer angular cut across the circle than the thickness set for the part.  This generally occurs with the diameter is small for the thickness selected... in other words you want a really thick ring for the diameter you select.
difference(){
    union(){
        //bottom hook
        translate([ring_outer_radius - bottomclip_dist_offcenterline + ringthickness , -ringthickness * bottonhookoffset_factor ,0])
        rotate([0,0,-bottom_rotation_factor]) //additional rotation for ring separation
        smallhalfring(1, "bottom");     // get the hook

        difference(){
            //this is the actual ring
           returnring(ring_outer_radius, ringthickness);

            //this cuts the gap out of the main circle between the hooks
            translate([ring_outer_radius- ringthickness *5/2,  -ringthickness * 2.5   ,-.1])
            cube([ringthickness * 5 ,ringthickness * 2.5 ,ringthickness + .4]);

        }
    }

    //cast square cut in case the ring is thicker than the opening...
     if (ringtype == "square") {
        translate([ring_outer_radius - bottomclip_dist_offcenterline + ringthickness , -ringthickness * bottonhookoffset_factor ,-ringthickness])
        rotate([0,0,-90])
        returnhook_squarecut();
     }

    //cast cyrcle cut in case the ring is thicker than the opening...
     if (ringtype == "round") {

        translate([ring_outer_radius - bottomclip_dist_offcenterline + ringthickness , -ringthickness * bottonhookoffset_factor + ringthickness * .25 - ringthickness * hooktoleranceratio  ,-ringthickness])
        rotate([0,0,-90])
        returnhook_roundcut();

       // translate([ring_outer_radius - bottomclip_dist_offcenterline + ringthickness , -ringthickness * 2.85 ,-ringthickness])
       // rotate([0,0,-90])
       // returnhook_roundcut();
     }

}
}

//main ring
module returnring(wheel_radius, tyre_diameter){
     $fa = 1;
    $fs = 0.4;
    //wheel_radius = 54;
    //tyre_diameter = 12;

    if (ringtype == "square") {
        rotate_extrude(angle=360) {
         translate([wheel_radius - tyre_diameter/2, 0])
          square(  tyre_diameter);
        } //rot
    } //if

     if (ringtype == "round") {
            translate([0,0, tyre_diameter/2]) // move it down to position of square extrude for consistency.
            rotate_extrude(angle=360) {
            translate([wheel_radius , 0])       // no - tyre_diameter/2 because the circle is centered
            circle(d=tyre_diameter);
            } //rotate
        } //if

}

module smallhalfring(capoffset, daside){
    difference(){

   union(){
   difference(){
       returnring(ringthickness, ringthickness);
       union(){
       translate([0,-ringthickness * 2,-1])
       cube(ringthickness * 4);
       //cube([2.1,2.1,6], center = true);
       }
   }
    //translate([0,capoffset * 2,1])
    //endcapangle();

    translate([-.2,capoffset * ringthickness ,ringthickness /2])
    rotate([0,0,10])
    endcapangle();

    } //union
        // cuts a larger cylinder shape of the diameter
        union(){
          cylinder(h=ringthickness * 3 ,d=ringthickness + ringthickness * hooktoleranceratio, center=true);

          // squares off the sides some for a better fit
            if (ringtype == "square")  returnhook_squarecut();
            if (ringtype == "round")  returnhook_roundcut();

         //translate([1.4,0, ringthickness * 1.4])
         //cube([ringthickness + ringthickness * hooktoleranceratio,ringthickness + ringthickness *       hooktoleranceratio, ringthickness * 3], center = true);

         if (daside == "top") {
        // on top hooks make more of a printable angle
        translate([ringthickness * .5 ,-ringthickness * .40,ringthickness * .5])
        rotate([0,0,-40])
       cube([ringthickness * 1.2, ringthickness, ringthickness], center = true);
         } //if

        } //U
   }

}

module returnhook_squarecut(){
         translate([1.4,0, ringthickness * 1.4])
         cube([ringthickness + ringthickness * hooktoleranceratio,ringthickness + ringthickness *       hooktoleranceratio, ringthickness * 3], center = true);
}

// cuts the hook to the tolerance set
module returnhook_roundcut(){
         translate([1.4,0, ringthickness * 1.4])
         cylinder(h=ringthickness * 3 ,d= ringthickness + ringthickness *  hooktoleranceratio, center=true);

}

module endcapangle(){
difference(){
    difference(){
            // cut the sphere in two
           sphere(ringthickness * .7); // was 1.4
          translate([-ringthickness * 4,-ringthickness * 2,-ringthickness * 2])
           cube(ringthickness * 3.9, center = false);
    }

    if (ringtype == "square"){
        // build a hollow cube to trim the sphere to fit the thickness
        rotate([0, 0, 0])
        difference(){
            cube( ringthickness * 1.5, center = true);
            cube([ringthickness * 3 ,ringthickness,ringthickness], center = true);
        }
    }

   if (ringtype == "round"){
        // build a hollow cube to trim the sphere to fit the thickness
        rotate([0, 90, 0])
        difference(){
            cylinder(h=ringthickness * 3,  d=ringthickness * 3 , center = true);
            cylinder(h=ringthickness * 3.1,  d=ringthickness , center = true);
        }
    }

}//diff
}

// --------- ORIGINAL NOT USED ----------------------------
module endcap(){
difference(){
    difference(){
            // cut the sphere in two
            sphere(ringthickness * .7); // was 1.4
          translate([-ringthickness * 4,-ringthickness * 2,-ringthickness * 2])
           cube(ringthickness * 4, center = false);
    }

    difference(){
    cube(3, center = true);
    cube([6,ringthickness,ringthickness], center = true);
    }}

}

```


[User]
I'd like to create a customizable keychain using OpenSCAD, and I need help designing it. The keychain will have a main body with three holes for Chicago screws, and optional ring attachment on one end. I'll be using Chicago screws for assembly, and small o-rings to separate the layers.

Here's a breakdown of the design:

**Overall Structure:** The keychain consists of a central body piece, possibly with two sides that mirror each other. These sides should be identical or optionally mirrored, and joined by Chicago screws. I need to be able to control the length of the keychain from the center screw to the left, and center screw to the right using variables called `len1` and `len2`.

**Chicago Screw Holes:**
*   There will be three main holes for the Chicago screws.
*   The central hole should be placed at the center of the main body piece.
*   The two outer holes should be spaced `len1` and `len2` distance away from the central hole on either side.
*   The holes should be designed to accommodate 5mm Chicago screws, but I need a parametric variable for the hole diameter. Let's call this `screw_diameter` and default it to 5mm. The hole should have a slightly larger diameter than the screw itself so it can fit, maybe `screw_diameter` + `screw_clearance` where `screw_clearance` defaults to 1mm.
*   I'd like the hole to be counterbored or have a larger diameter section on each side to hide the head of the Chicago screw, so the hole should be wider on the top and bottom of the keychain. The counterbore diameter should be controlled by a `screw_head_diameter` variable (default to 10mm), and the depth of the counterbore by a `screw_head_depth` variable (default to 2mm).
* The main body of the screw hole should be a cylinder of depth controlled by variable `screw_main_depth`, which defaults to the overall depth of the keychain (let's call that `keychain_depth` and default it to 5).

**Shape:**
*   The body will be generally rectangular with rounded edges. I'm thinking something like a rounded rectangle, where the ends are semicircles.
*   The width of the body piece should be controlled with a variable, `keychain_width`, defaulting to 30mm.
* The edge of the rounded rectangle should be controlled by a variable `edge_curve` and defaulting to 5.
*   The thickness (or z-depth) should also be a variable `keychain_depth`, which I mentioned defaulting to 5mm, and which we'll need for calculating the depth of the screw holes.
*   I'd like the corners of the rectangle to be filleted; the curvature of this fillet should be controllable with a variable, perhaps called `edge_curve`.

**Ring Attachment:**
*   There should be an optional ring attachment on one end controlled by a `ring` boolean variable.
*   The ring should be a simple loop.
*   If `ring` is true, I would like it to attach to the right-most screw.

**Double-Sided:**
*   There should be a `doublesided` boolean variable controlling whether to mirror the left side of the keychain. If `doublesided` is true, then the right side of the keychain should be mirrored to the left side and positioned using the `len1` and `len2` variables. If it is false, then only one half of the keychain is created, as would be appropriate for a tag.

**Libraries:**
I'll need to use the `MCAD/2Dshapes.scad` library for the pieSlice function.

**Customizer:**
*   `len1` - Distance from the center screw to the right screw.
*  `len2` - Distance from the center screw to the left screw.
*   `screw_diameter` - Diameter of the main screw hole.
*   `screw_clearance` - Clearance between the screw and the hole.
*   `screw_head_diameter` - Diameter of the screw head counterbore.
*   `screw_head_depth` - Depth of the screw head counterbore.
*  `screw_main_depth` - Depth of the main screw hole cylinder.
*   `keychain_width` - Width of the keychain body.
*  `keychain_depth` - Depth of the keychain body
*   `edge_curve` - Curvature of rounded edges and fillets.
*   `ring` - Boolean to enable/disable the ring attachment.
*   `doublesided` - Boolean to enable/disable the mirroring of the left side of the keychain.

Could you please generate the OpenSCAD file(s) for this keychain design?

[Assistant]
Keychain.scad:
```
use <MCAD/2Dshapes.scad>;

$fa= 30; $fn=50; $fs=30;
len1 = 40;
len2 = 40;
ring = true;
doublesided = true;

module rotate_about_pt(z, y, pt) {
    translate(pt)
        rotate([0, y, z]) // CHANGE HERE
            translate(-pt)
                children();
}

module RoundedCube(x=5, y=5, z=2, curve=1){

translate([0, curve, 0])
cube([x, y-(curve*2), z]);

translate([0, y-curve, 0])
rotate([90, 0, 90])
linear_extrude(x)
pieSlice([curve, z], 0, 90);

translate([0, curve, 0])
rotate([90, 0, 90])
mirror([1, 0, 0])
linear_extrude(x)
pieSlice([curve, z], 0, 90);

}

module RoundedCylinder(h=2, r=3, curve=1){

cylinder(h=h, r=r-curve);
rotate_extrude(angle=360)
translate([r-curve, 0, 0])
pieSlice([curve, h], 0, 90);

}

module Hole(tot_z = 5, upper_z = 2, upper_r= 10, lower_r=6){

cylinder(h=tot_z-upper_z, r=lower_r);

translate([0, 0, tot_z-upper_z])
cylinder(h=upper_z, r=upper_r);

}

module LatHole(x=4, y=4, z=2){

translate([0, y/2, 0])
cylinder(h=z, r=y/2);

cube([x-y/2, y, z]);

translate([x-y/2-1, -1, 0])
difference(){
cube([1, 1, z]);
cylinder(h=z, r=1);
    }

translate([x-y/2-1, y+1, 0])
mirror([0, 1, 0])
difference(){
cube([1, 1, z]);
cylinder(h=z, r=1);
    }

    }

module KeychainSide(x=10, y=5, z=2, hole_width=15, curve=1, closed=false){

difference(){

    union(){
translate([0, y/2, 0])
union(){
RoundedCylinder(z, y/2, curve);
if (closed==true){
translate([x-y/2, 0, 0])
RoundedCylinder(z, y/2, curve);}
}
RoundedCube(x-y/2, y, z, curve);

}
    union(){
translate([-y/6, y/2, 0])
Hole(5, 2, 5, z/2);

translate([x-y/2, y/2, 0])
Hole(5, 2, 5, z/2);

translate([x-hole_width-7, y-hole_width/2, 0])
rotate([0, 0, 90])
LatHole(y/2, hole_width, z);

    }
}
}

module ring(height=4, hole_r=2, border=2) {
translate([-(hole_r*2+border*2)+6, -hole_r-border,0])
difference(){
    union(){
        cube([hole_r*2+border*2, hole_r*2+border*2, height]);
        translate([0, hole_r+border, 0])
            cylinder(h=height, r=hole_r+border);
    }
    translate([0, hole_r+border, 0])
    cylinder(h=height, r=hole_r);
    }}

module Keychain(length_1=40, length_2=40, ring=false, doublesided=true){

width=30;

len_1 = length_1 + width/2 - width/6;
len_2 = length_2 + width/2 - width/6;

KeychainSide(len_1, width, 5, 15, 5, !doublesided);
if (ring==true){
    rotate([0, 0, 90])
    ring();}

translate([len_1+len_2-width, width, 0])
rotate([0, 0, 180])
if (doublesided==true){KeychainSide(len_2, width, 5, 15, 5);}

}

 Keychain(max(len1, 27), max(len2, 40), ring, doublesided);
 translate([0, 62, 0])
 mirror([0, 1, 0])
 Keychain(max(len1, 27), max(len2, 40), false, doublesided);
```


[User]
Hey, I'm looking to design some plant labels for my flower garden, and I'd like to use OpenSCAD to make them customizable. I've already created a design but I would like to try to get help with making a better design that is more easily modified using parameters, maybe with better use of libraries.

My current design involves extruded text for the plant name, and a stake with a pointed end. I'll give you the code I'm using so you know what I'm talking about:

```
// Customizable Flowering Plant Label Stake
// by Mark Thompson

text_string = "Plant";
text_size = 12;
text_thickness = 3;
text_font = "Nimbus Sans L:Bold";
text_y_offset_adjust = 0;

stake_length = 125;
stake_thickness = 5;
stake_height = 5;

point_length = 10;
tip_size = 0.5;

{
    translate([0,text_y_offset_adjust,0])
        linear_extrude(height=text_thickness, convexity=4)
            text(text_string,size=text_size,font=text_font);

    translate([stake_length/2,-stake_height/2,stake_thickness/2]) {
        difference() {
            hull() {
                cube([stake_length,stake_height,stake_thickness],true);
                translate([stake_length/2+point_length,stake_height/2-tip_size/2,-stake_thickness/2+tip_size/2])
                    cube([tip_size,tip_size,tip_size],true);
            }

            translate([0,-stake_height/2,stake_thickness/2])
                cube([stake_length+point_length*2+0.1,stake_height,stake_thickness],true);
        }
    }
}
```

Ideally, the design should be parameterized so I can adjust things like the text, its size and thickness, the font, the length and thickness of the stake, the point length and tip size, and the vertical position of the text.

I'm not super experienced, but I've heard good things about BOSL2 and maybe the "textplus" module? If those are useful or any other libraries, feel free to make use of them. I want to be able to easily change these parameters in the file itself (not just through a customizer UI, since I want to keep the design on my local machine).

Could you help me design a new parametric OpenSCAD file for this? Thanks!

[Assistant]
flower-sign.scad:
```
// Customizable Flowering Plant Label Stake
// by Mark Thompson

text_string = "Plant";
text_size = 12;
text_thickness = 3;
text_font = "Nimbus Sans L:Bold";
text_y_offset_adjust = 0;

stake_length = 125;
stake_thickness = 5;
stake_height = 5;

point_length = 10;
tip_size = 0.5;

{
    translate([0,text_y_offset_adjust,0])
        linear_extrude(height=text_thickness, convexity=4)
            text(text_string,size=text_size,font=text_font);

    translate([stake_length/2,-stake_height/2,stake_thickness/2]) {
        difference() {
            hull() {
                cube([stake_length,stake_height,stake_thickness],true);
                translate([stake_length/2+point_length,stake_height/2-tip_size/2,-stake_thickness/2+tip_size/2])
                    cube([tip_size,tip_size,tip_size],true);
            }

            translate([0,-stake_height/2,stake_thickness/2])
                cube([stake_length+point_length*2+0.1,stake_height,stake_thickness],true);
        }
    }
}
```


[User]
Hey, I'm looking to create a parametric T-slot clamp design using OpenSCAD. I've seen some designs out there, but I want one that's flexible and easily customizable. It should have two main parts: a jaw that slides onto the T-slot extrusion and a cam lever that locks it in place.

Here are the parameters I'd like to control:

*   **`part`:** This should be an option to render "Both" parts together, just the "Jaw", or just the "Cam". This would be super helpful for printing the parts with different materials or colors.

*   **`extrusion_type`**: I need to be able to select from a few common extrusion types:
    *   "M1515": Misumi 15mm extrusion.
    *   "M2020": Misumi 20mm extrusion.
    *   "2020": Standard 20mm extrusion (like a V-slot).
    *   "80/20 1010": 80/20 1" extrusion.
    *  "80/20 20-2020": 80/20 20mm extrusion.
    *   "OpenBeam": OpenBeam 15mm extrusion.
    *   "MicroRax": MicroRax 10mm extrusion.

*   **`clamp_len`:**  The length of the clamp along the extrusion. This directly affects grip so I want to be able to adjust it.

*   **`jaw_len`:** The overall length of the jaw.

*   **`groove_depth`:** The depth of guiding grooves on the jaw. I want to set this to 0 if I don't want any grooves.

*  **`flip_cam`**: This should allow me to flip the orientation of the cam lever when clamped.  A value of -1 would make the lever point towards the jaw when locked, and 1 would make the lever point away from the jaw.

*   **`lever_nub`:** A boolean (0 or 1) that toggles a small nub on the lever to limit its rotation.

*   **`pad_ratio`:** A ratio to define the length of a pad at the end of the jaw, based on the jaw length.

I need the code to define the dimensions of the extrusions, including the groove dimensions, as well as the other parameters.  I am also going to need a 'clearance' variable to make sure parts fit well.

I'd prefer if you could include a simple logo as part of the jaw, something like an "MGX" - I have seen how to do this already but it would be easier if it was already in the design, and you do not need to be too precise with this logo.

Finally, I would like the parts to fit together.

I do not have any libraries of my own, so it would be best to generate all of the code.

Thanks!

[Assistant]
ex_clamp.scad:
```
// Quick T-Slot Clamp
// Design by Marius Gheorghescu (@mgx3d), July 2017

part = "Both"; //[Both: Render both jaw and cam, Jaw: Render just the jaw, Cam: Render just the cam]

// Chose the extrusion type
extrusion_type = "2020"; // [M1515:Misumi 15mm (1515),M2020:Misumi 20mm (2020),2020:Standard 20mm (2020),80/20 1010:80/20 1" (1010),80/20 20-2020:80/20 20mm (20-2020), OpenBeam:OpenBeam 15mm,MicroRax: MicroRax 10mm]

// length of the clamp on the extrusion (longer => better grip)
clamp_len = 30; // [10:100]

// length of the jaw in milimeters
jaw_len = 100; // [10:500]

// jaw guiding grooves depth (set to 0 for no grooves)
groove_depth = 3; // [0:0.1:5]

//flip lever arm direction
flip_cam = -1; //[-1: lever towards jaw when locked, 1: lever towards bar when locked(suggest also no lever_nub)]

// Add a nub to the lever to limit rotation?
lever_nub = 0; // [0,1]

// Pad grooves as a ratio of jaw (total clamp length is jaw + jaw*pad)
pad_ratio = 1; // [0.0:0.1:1.0]

/* [Hidden] */

wall_thickness = groove_depth+2;

extrusion_size =
    (extrusion_type == "M1515")?15:
    (extrusion_type == "M2020")?20:
    (extrusion_type == "2020")?20:
    (extrusion_type == "80/20 1010")?25.4:
    (extrusion_type == "80/20 20-2020")?20:
    (extrusion_type == "OpenBeam")?15:
    (extrusion_type == "MicroRax")?10:
    10;

extrusion_groove_min =
    (extrusion_type == "M1515")?3.55:
    (extrusion_type == "M2020")?6.15:
    (extrusion_type == "2020")?5:
    (extrusion_type == "80/20 1010")?6.5:
    (extrusion_type == "80/20 20-2020")?5.15:
    (extrusion_type == "OpenBeam")?3.25:
    (extrusion_type == "MicroRax")?4.90:
    3.3;

extrusion_groove_max =
    (extrusion_type == "M1515")?5.5:
    (extrusion_type == "M2020")?11.75:
    (extrusion_type == "2020")?10:
    (extrusion_type == "80/20 1010")?14.5:
    (extrusion_type == "80/20 20-2020")?11.75:
    (extrusion_type == "OpenBeam")?5.75:
    (extrusion_type == "MicroRax")?6.0:
    5.5;

extrusion_groove_lip =
    (extrusion_type == "M1515")?1.15:
    (extrusion_type == "M2020")?2.3:
    (extrusion_type == "2020")?2.3:
    (extrusion_type == "80/20 1010")?2.4:
    (extrusion_type == "80/20 20-2020")?1.55:
    (extrusion_type == "OpenBeam")?1.45:
    (extrusion_type == "MicroRax")?1.0:
    1.0;

extrusion_groove_depth =
    (extrusion_type == "M1515")?4.2:
    (extrusion_type == "M2020")?6.1:
    (extrusion_type == "2020")?5.5:
    (extrusion_type == "80/20 1010")?7.2:
    (extrusion_type == "80/20 20-2020")?6.0:
    (extrusion_type == "OpenBeam")?4.2:
    (extrusion_type == "MicroRax")?3.1:
    4.0;

epsilon = 0.01;

cam_dia = min(extrusion_size*0.8, clamp_len/2);
cam_z_offset = cam_dia/2 ;
cam_lock_offset = 1;

// slide-in clearance between parts
clearance = 0.25;

$fn=100;

pad_len = epsilon + jaw_len*pad_ratio;

module round_rect_ex(x1, y1, x2, y2, z, r1, r2)
{
    brim = z/10;

    hull() {
        translate([-x1/2 + r1, y1/2 - r1, z/2-brim/2])
            cylinder(r=r1, h=brim,center=true);
        translate([x1/2 - r1, y1/2 - r1, z/2-brim/2])
            cylinder(r=r1, h=brim,center=true);
        translate([-x1/2 + r1, -y1/2 + r1, z/2-brim/2])
            cylinder(r=r1, h=brim,center=true);
        translate([x1/2 - r1, -y1/2 + r1, z/2-brim/2])
            cylinder(r=r1, h=brim,center=true);

        translate([-x2/2 + r2, y2/2 - r2, -z/2+brim/2])
            cylinder(r=r2, h=brim,center=true);
        translate([x2/2 - r2, y2/2 - r2, -z/2+brim/2])
            cylinder(r=r2, h=brim,center=true);
        translate([-x2/2 + r2, -y2/2 + r2, -z/2+brim/2])
            cylinder(r=r2, h=brim,center=true);
        translate([x2/2 - r2, -y2/2 + r2, -z/2+brim/2])
            cylinder(r=r2, h=brim,center=true);

    }
}

// groove slider with 0-reference on the face of the extrusion
module groove_clamp(len, depth)
{
    radius = 0.3;

    difference() {
        union() {
            hull() {

                translate([-extrusion_groove_max/2 + radius, -radius - extrusion_groove_lip, 0])
                    cylinder(r=radius, h=len, center=true);

                translate([extrusion_groove_max/2 - radius, -radius - extrusion_groove_lip, 0])
                    cylinder(r=radius, h=len, center=true);

                translate([0, - min(extrusion_size/2, extrusion_groove_max*cos(45)) + radius - extrusion_groove_lip, 0])
                    cylinder(r=radius, h=len, center=true);
            }

            // extension
            hull() {
                translate([0, -extrusion_groove_lip/2 - epsilon, 0])
                    cube([extrusion_groove_min, extrusion_groove_lip, len], center=true);

                translate([0, depth, 0])
                    cube([extrusion_groove_min, extrusion_groove_lip, cam_dia], center=true);

                translate([0, depth, 0])
                    cube([extrusion_groove_min, extrusion_groove_lip, len], center=true);

            }
        }

        // clear bottom of the groove
        translate([0, -extrusion_groove_depth - extrusion_groove_max/2, 0])
            cube([extrusion_groove_max, extrusion_groove_max, len + epsilon], center=true);

    }
}

module logo()
{
    rotate([-90,0,90]) {
    intersection() {
        union() {
            difference() {
                round_rect_ex(3, 10, 3, 10, 2, 1, 1);
                round_rect_ex(2, 9, 2, 9, 3, 1, 1);
            }

            translate([2.5, 0, 0])
                difference() {
                    round_rect_ex(3, 10, 3, 10, 2, 1, 1);
                    round_rect_ex(2, 9, 2, 9, 3, 1, 1);
                }
        }

        translate([0, -3.5, 0])
            cube([20,4,10], center=true);
    }

    translate([1.25, -2.5, 0])
        difference() {
            round_rect_ex(8, 7, 8, 7, 2, 1, 1);
            round_rect_ex(7, 6, 7, 6, 3, 1, 1);

            translate([3,0,0])
                cube([4,2.5,3], center=true);
        }

    translate([2.0, -1.0, 0])
        cube([8, 0.5, 2], center=true);

    translate([0,-2,0])
        cylinder(r=0.25, h=2, center=true, $fn=12);

    translate([2.5,-2,0])
        cylinder(r=0.25, h=2, center=true, $fn=12);
    }

}

module arm() {

    cam_shaft_clearance = 0.5;

    translate([0,0,-clamp_len/2])
    difference() {

        hull() {
            // extrusion shell
            translate([extrusion_size/4,0,0])
               cube([extrusion_size/2, extrusion_size, clamp_len], center=true);

            // pad
            translate([jaw_len - pad_len/2, 0, clamp_len/2 - wall_thickness/2])
               cube([pad_len, extrusion_size, wall_thickness], center=true);

        }

        // save material / add strength
        translate([jaw_len/2 - epsilon + extrusion_size, extrusion_size/5, -wall_thickness])
            cube([jaw_len , extrusion_size/5, clamp_len], center=true);

        translate([jaw_len/2 - epsilon + extrusion_size, -extrusion_size/5, -wall_thickness])
            cube([jaw_len, extrusion_size/5, clamp_len], center=true);

        // longitudinal groove
        translate([jaw_len - pad_len/2, 0 ,clamp_len/2])
        rotate([0,90,0])
        rotate([0,0,45])
            cube([groove_depth, groove_depth, pad_len], center=true);

        // cross-grooves
        translate([jaw_len - pad_len/2, 0, clamp_len/2 - wall_thickness/2])
        for(i=[0:max(extrusion_size/4, groove_depth*2):pad_len]) {
            translate([i-pad_len/2,0,wall_thickness/2])
            rotate([90,0,0])
            rotate([0,0,45])
            cube([groove_depth, groove_depth, extrusion_size + jaw_len], center=true);
        }
    }
}

module cam_lever()
{
    lever_len = clamp_len+extrusion_size/4;

    difference() {
        union() {

            // cam shaft
            translate([0, 0, extrusion_size/2])
                cylinder(r=cam_dia/2, h=extrusion_size, center=true);

            // handle
            translate([0, 0, -cam_dia/4 + epsilon])
            {
                // handle
                translate([0, 0, cam_dia/8])
                hull() {
                    cylinder(r=cam_dia/2, h=cam_dia/4, center=true);

                    translate([0, lever_len, 0])
                        cylinder(r=cam_dia/4, h=cam_dia/4, center=true);
                }

                if (lever_nub) {
                    // nub to prevent flipping around
                    translate([0, lever_len, cam_dia/4 + cam_dia/8 - epsilon])
                        cylinder(r=cam_dia/4, h=cam_dia/4, center=true);
                }

                // bevel
                translate([0, 0, -cam_dia/8 +epsilon])
                hull() {
                    cylinder(r1=cam_dia/4, r2=cam_dia/2, h=cam_dia/4, center=true);
                    translate([0, lever_len, 0])
                        cylinder(r1=cam_dia/8, r2=cam_dia/4, h=cam_dia/4, center=true);
                }

            }
         }

         // offset groove
         translate([0, flip_cam*cam_lock_offset, extrusion_size/2 - extrusion_groove_min/2])
         difference() {

            translate([0, 0, extrusion_groove_min/2 + cam_dia/2 + clearance])
                cylinder(r=cam_dia, h=extrusion_groove_min + cam_dia + 2*clearance, center=true);

            cylinder(r=cam_dia/2 - cam_lock_offset, h=extrusion_size, center=true);
            translate([0,0,cam_dia/2 + extrusion_groove_min - epsilon])
                cylinder(r1=cam_dia/2 - cam_lock_offset, r2=cam_dia*1.5, h=cam_dia, center=true);

         }
    }
}

module jaw()
{
    depth = extrusion_size/2 - extrusion_groove_lip/2;
    height = clamp_len;

    difference() {
        union() {
            groove_clamp(height, depth);

            // cam rider
            translate([0, cam_z_offset + cam_lock_offset*0, 0])
            rotate([90,0,90])
                cylinder(r=cam_dia/2 + cam_lock_offset, h=extrusion_groove_min, center=true);

            difference() {
                translate([0,clearance, -clamp_len/2])
                rotate([0,180,-90]) arm();

                // cam shaft clearance
                translate([0, cam_z_offset + cam_lock_offset*0, 0])
                rotate([90,0,90])
                    hull() {
                        cylinder(r=cam_dia/2 + clearance, h=60, center=true);

                        translate([-cam_lock_offset,0,0])
                            cylinder(r=cam_dia/2 + clearance, h=60, center=true);

                        translate([-cam_lock_offset - cam_dia, cam_dia/2,0])
                            cylinder(r=cam_dia/2 + clearance, h=60, center=true);
                    }
            }
        }

        translate([0, cam_z_offset - cam_lock_offset*1.5, 0])
        rotate([90,0,90])
            hull() {
                cylinder(r=cam_dia/2 + clearance, h=60, center=true);
            }

        //translate([extrusion_size/2 + 0.25, cam_z_offset + cam_dia, -2 - ((jaw_len < 40)?cam_dia/2:0)])
        translate([-1, extrusion_groove_lip + 0.5, clamp_len/2 + 0.5])
        rotate([0,-90,-90])
        scale((extrusion_size*1.5 - 8)/extrusion_size)
            logo();

    }

}

module clamp()
{
    depth = cam_dia;
    height = clamp_len;
    cam_shaft_clearance = 0.25;

    //translate([0,0,-clamp_len/2])

    difference() {
        union() {
            hull() {
                // extrusion shell
                translate([extrusion_size/4,0,0])
                   cube([extrusion_size/2, extrusion_size, clamp_len], center=true);

                // pad
                translate([extrusion_size/2 + jaw_len, 0, -clamp_len/2 + wall_thickness/2])
                   cube([pad_len, 0*2*wall_thickness + extrusion_size, wall_thickness], center=true);

                translate([cam_z_offset, 0,  0])
                rotate([0,90,90])
                    cylinder(r=cam_dia/2 + clearance + wall_thickness, h=extrusion_size, center=true);

            }
        }

        // locking plate clearance
        translate([jaw_len/2- epsilon,0, wall_thickness])
            cube([jaw_len, extrusion_groove_min, clamp_len+epsilon], center=true);

        // clear material
        translate([jaw_len/2 + pad_len/2 - epsilon + extrusion_size/2, 0, wall_thickness])
            cube([jaw_len + pad_len, extrusion_size/2, clamp_len], center=true);

        // longitudinal groove
        translate([(extrusion_size + jaw_len)/2 + extrusion_size,0, -clamp_len/2])
        rotate([0,90,0])
        rotate([0,0,45])
            cube([groove_depth, groove_depth, extrusion_size + jaw_len + pad_len], center=true);

        // cross-grooves
        translate([0*wall_thickness + extrusion_size/2 + jaw_len, 0, -clamp_len/2 - wall_thickness/2])
        for(i=[extrusion_size/4:extrusion_size/4:pad_len]) {
            translate([pad_len/2 - i,0,wall_thickness/2])
            rotate([90,0,0])
            rotate([0,0,45])
            cube([groove_depth, groove_depth, extrusion_size + jaw_len], center=true);
        }

        // cam shaft clearance
        translate([cam_z_offset, 0,  0])
        rotate([0,90,90])
            cylinder(r=cam_dia/2 + clearance, h=60, center=true);
    }
}

module locking_plate()
{
    difference() {

        union() {
            groove_clamp(clamp_len, cam_z_offset + cam_dia/2 + wall_thickness);

            harden_len = cam_z_offset + cam_dia/2 - extrusion_size/2 + wall_thickness + extrusion_groove_lip;

            translate([0, extrusion_size/2 + harden_len/2, 0])
                cube([extrusion_size/2, harden_len, clamp_len], center=true);
        }

        // cam shaft clearance
        translate([0, cam_z_offset - extrusion_groove_lip, -wall_thickness])
        rotate([0,90,0])
            cylinder(r=cam_dia/2 + clearance, h=extrusion_size, center=true);
    }

}

// show assembled?
if (0) {

    color([0.2,0.2,0.2,1.0]) jaw();
    color("red") translate([ -extrusion_size/2, cam_z_offset, 0]) rotate([90,0,90])
        cam_lever();

    %translate([0, -extrusion_size/2, 0]) cube([extrusion_size, extrusion_size, 5*clamp_len], center=true);

} else {
    if (part == "Both")
    {
    jaw();
    translate([extrusion_size, 0, -clamp_len/2 +cam_dia/2]) cam_lever();
    }
    else if ( part == "Jaw" )
    {
        jaw();
    }
    else if ( part == "Cam" )
    {
        cam_lever();
    }
}

```


[User]
Hey, I'm working on a pinewood derby trophy and I'd like to have a custom version made using OpenSCAD. It's basically a tiered design with a rotating text band, and I need it to be parametric.

Here's how it breaks down:

**Base:** I'd like a simple cylinder for the base, it should be parametric with settable height and radius.

**Hub:** This sits on top of the base. It's another cylinder, but smaller, and also needs to be parametric for height and radius. This should have a small height and radius offset from the base.

**Text Ring:** This is the tricky part. I need a donut-shaped object with text extruded onto it. The text needs to be able to be customized, of course, and wrap around the circumference of the donut. I'll need parameters for:
*   The text itself.
*   The donut's inner and outer radius.
*   The donut's thickness (both radial and along the Z axis)
*   The text's font and size.

**Stand:**  Finally, I need a stand to hold the pinewood car at the very top. This is a simple upright that also needs to be parametric, specifically its height. I'd like a simple hole running through it in the Z axis, where it sits near the car itself to pass a pipe cleaner through to attach the car.

Essentially, I need an OpenSCAD file (or a set of files) that creates these four parts which will stack together, with parameters that control the sizes of each component, and particularly the text ring (including the text content). Ideally, I'd like to avoid using modules that are dependent on anything outside of core OpenSCAD - I don't really want to use MCAD or BOSL this time.

Can you create that for me?

[Assistant]
round_text.scad:
```
text="|        Pack 400, 2021 Pinewood Derby        |";

scale([.8,.8,.8])ring();

module ring() {
   difference() {
      translate([0,0,2])difference(){
         cylinder(4,70,70, center=true);
         translate([0,0,-.5])cylinder(5,50,50,center=true);
      }
      translate([0,0,4])rotate([0,180,0])round_text();
   }

   translate([0,0,4])difference(){
      cylinder(2,70,70, center=true);
      translate([0,0,-.5])cylinder(3,50,50,center=true);
   }
}

module round_text() {
   for(i=[5:.5:355]){
      rotate([0,0,180-i])translate([180-i,50,0])intersection() {
         translate([i-180,10,0])cube([1,20,12],center=true);
         translate([-180,5.5,0])resize([360,16,10])linear_extrude(10)text(text);
      }
   }
}

```


[User]
Okay, I'm looking to create a parametric wind turbine model for 3D printing, and I'd like the design to be flexible enough to fit onto an existing knob mechanism. I'm providing the basic code I used to create a specific instance of this, but I would like it to be far more parametric and customizable. Here's a breakdown of the features I need, and I'd like it to be generated using OpenSCAD:

**Overall Structure:**

*   **Base Turbine Shape:** The main body of the turbine should have a cylindrical shape that can optionally taper from the bottom to the top.
*   **Blades:**  I need turbine blades that can be twisted along the height of the turbine, similar to a propeller. I also want to be able to add curvature to the blades themselves, like a subtle arc or a simple straight edge. The number of blades should be adjustable, with a minimum of 2 and no maximum.
*   **Center Stem:** A central cylinder connects the blades to the base, it can also be tapered, for connecting to a driving shaft.
*   **Knob Mount:** There should be a section at the base of the turbine designed to fit onto a knob. This should allow for configurable knob size, total height, and a configurable number of finger indents around the circumference of the knob. The finger indents also need to be configurable in terms of their depth into the knob and diameter, as well as the ability to taper the edges of the finger indents. Finally, the mount also needs to have a cylindrical cutout, whose diameter is configurable, to fit onto a shaft.
*   **Material Thickness:** I need control over the thickness of the turbine blades.
*   **Print Settings:** I want to be able to set the printing layer height, which will control the precision of the final model (This is for the model generation, not the printing itself. I just need the model to be correct based on these).

**Key Parameters:**

*   **Overall Scale:** A general scaling factor for the entire model (e.g., `scl = 1;` for actual sizes)
*   **Turbine Dimensions:**
    *   `turbine_height`: Total height of the main body of the turbine.
    *   `blade_radius`: Radius from the center of the turbine to the edge of the blades.
    *   `bot_r`: Radius at the bottom of the turbine body.
    *   `top_r`: Radius at the top of the turbine body. Allows for a tapered cylindrical body.
    *   `blade_thickness`: Thickness of the turbine blades.
*   **Blade Parameters:**
    *   `num_blades`: Number of blades on the turbine.
    *    `pitch_angle`: Angle of the twist/pitch along the turbine height (in degrees) (i.e. higher angle = higher pitch)
    *   `blade_arch`: The amount of curvature of the blades (a higher value makes the blades more curved)
    *   `apply_curvature`: A boolean to specify whether the blades should have a curved edge or a straight edge
    *   `rotation_dir`: Set the direction of the twist of the blades, 1 for clockwise and -1 for counter-clockwise
*   **Center Stem Dimensions:**
    *   `stem_bot_r`: Radius at the bottom of the stem
    *   `stem_top_r`: Radius at the top of the stem
*   **Shaft Fitting:**
    *   `shaft_fit_r`: Radius of the shaft cutout.
    *   `shaft_fit_l`: Length/depth of the shaft cutout.
*   **Knob Parameters:**
    *   `Knob`: Boolean to specify whether to include a knob
    *   `KnobDiameter`: Diameter of the knob.
    *   `KnobTotalHeight`: Total height of the knob.
    *   `FingerPoints`: Number of finger indents on the knob.
    *    `FingerHoleDiameter`: Diameter of the finger indents.
    *   `TaperFingerPoints`: Boolean to specify whether to taper the sides of the finger indents
*  **Other:**
   *   `printer_layer_height`: Height of each print layer (for slicing accuracy).
   *    `percent_offset`: Percent of turbine height with blades at blade radius (ie. if the percent offset is 50, then 50% of the height will have a blade radius, while the bottom 50% of the turbine height will have a gradually increasing radius.
   *    `tol`: Tolerance for fitment
   *    `AT`: Tolerance for geometric connections.
   *    `ST`: Tolerance for geometric connections.
   *    `TT`: Tolerance for geometric connections.
*   **Curve Resolution:**
    *   `$fa`, `$fs`, `$fn`: Standard OpenSCAD parameters for curve quality.

**Specific Features:**

*   **Tapering Blades:** The blades should twist smoothly along the turbine height.
*   **Curved Blades:** If the curvature setting is enabled, the blades should be curved.
*   **Parametric Knob:** The knob should be fully parametric as described above.
*   **Smooth Transitions:** There should be smooth transitions in any curved geometry.
*   **Correct Slicing:** The slicing of the cylinder should be handled correctly.
*  **Non-Linear Extrusion:** Make sure that the non-linear extrusion of the turbine body from base to top will also allow for a linear body (ie. no change in radius over the height), with an optional taper.

I think that's everything! I'm really looking forward to seeing how the generated code will work out. I'm expecting to use this for an existing project where I need to generate the model programmatically for custom purposes, so I need to be able to adjust any of these parameters individually. I would also prefer that the code would not require any external libraries to run.

[Assistant]
Turbine_generator.scad:
```
// Overall scale (to avoid small numbers, internal faces or non-manifold edges)
scl = 1;
// Layer height (for ring horizontal split)
layer_h_ = 0.2; //[0:0.01:1]
// Gear clearance
tol_=0.2; //[0:0.01:0.5]
// Tolerances for geometry connections.
AT_=1/64;
// Curve resolution settings, minimum angle
$fa = 5/1;
// Curve resolution settings, minimum size
$fs = 1/1;
// Curve resolution settings, number of segments
$fn=96;
//Include a knob
Knob = 1;				// [1:Yes , 0:No]
//Diameter of the knob, in mm
KnobDiameter = 15.0;			//[10:0.5:100]
//Thickness of knob, including the stem, in mm:
KnobTotalHeight = 15;			//[10:thin,15:normal,30:thick, 40:very thick]
//Number of points on the knob
FingerPoints = 6;   			//[3,4,5,6,7,8,9,10]
//Diameter of finger holes
FingerHoleDiameter = 5; //[5:0.5:50]
TaperFingerPoints = true;			// true

//layer_h = scl*layer_h_;
tol = scl*tol_;
AT=AT_*scl;
ST=AT*2;
TT=AT/2;

module knob(){
    // Knob by Hank Cowdog 2 Feb 2015, somewhat modified
    //Diameter of the shaft thru-bolt, in mm
    ShaftDiameter = 0;
    ShaftEasingPercentage = 0/100.0;  // 10% is plenty
    NutFlatWidth = 1.75 * ShaftDiameter;
    NutHeight =     0.87 * ShaftDiameter;
    SineOfSixtyDegrees = 0.86602540378/1.0;
    NutPointWidth = NutFlatWidth /SineOfSixtyDegrees;
    EasedShaftDiameter = ShaftDiameter * (1.0+ShaftEasingPercentage);
    // center gears and knob

        if(Knob)
            intersection(){
                translate([0,0,KnobTotalHeight])mirror([0,0,1])difference(){
                    // The whole knob
                    cylinder(h=KnobTotalHeight+TT, r=KnobDiameter/2, $fn=24);
                    // each finger point
                    for (i = [0 : FingerPoints-1]){
                        rotate( i * 360 / FingerPoints, [0, 0, 1])
                        translate([(KnobDiameter *.6), 0, -1])
                        union() {
                            // remove the vertical part of the finger hole
                            cylinder(h=KnobTotalHeight+2, r=FingerHoleDiameter/2, $fn=24);
                            // taper the sides of the finger points
                            if(TaperFingerPoints) {
                                rotate_extrude(convexity = 10, $fn=24)
                                    translate([FingerHoleDiameter/2.0, 0, 0])
                                    polygon( points=scl*[[2,-3],[-1,6],[-1,-3]] );
                            }
                        }
                    }
                    // Drill the shaft
                    translate([0,0,KnobTotalHeight+1])scale([1,1,-1])union(){
                        //The thru-shaft
                        cylinder(h=KnobTotalHeight+2, r=EasedShaftDiameter/2., $fn=24);
                    }
                    // taper the ends of the points
                    if(TaperFingerPoints) {
                        rotate_extrude(convexity = 10, $fn=24)
                        translate([KnobDiameter/2, 0, 0])
                        polygon( points=scl*[[-2,-3],[1,6],[1,-3]] );
                    }
                }
                // Transition knob to gear. Cutout overhanging teeth at angle
                //gear2D(dt[modules-1],cp[modules-1]*PI/180,P,depth_ratio2,depth_ratio,tol,KnobTotalHeight,AT);
        }
    }

//Denise Lee, 12March2017

/*
//In RC hobby propeller nomenclature
//Propeller diameter X distance travelled per revolution (in silly inches!)
inch_mm = 25.4;
prop_dia = 6; //propeller diameter
prop_dist = 3.8; //propeller distance travelled
blade_radius = prop_dia*inch_mm/2;
pitch_angle = atan(prop_dist*inch_mm/blade_radius);
*/

blade_radius = 120;
pitch_angle = 30; //Converting pitch to twist angle for linear extrude

blade_arch = blade_radius/11; // Curvature of blades, selected straight edge or use ARC module
apply_curvature = 1; //1 Curve blades, 0 for straight edge

echo("Blade Radius", blade_radius);
echo("Pitch Angle", pitch_angle);
echo("Blade Arch", blade_arch);

printer_layer_height = 0.2; //for preview (F5) x20, set this to 0.1 for rendering for export STL(F6)!!!
blade_thickness = 2; //thickness of blade
turbine_height = 15;
num_blades = 3;
rotation_dir = 1; //CCW = -1, CW = 1

pi = 3.14159265359;
blade_cirf = 2*pi*blade_radius;
twist_angle = 360*turbine_height/(blade_cirf*tan(pitch_angle));

echo("Twist Angle: ", twist_angle);

slicing = turbine_height / printer_layer_height; //equal printing slicing height

percent_offset = 50; //Percent of turbine height with blades at blade radius
//offset_slicing must be greater or equal slicing
offset_slicing = round(slicing*(1/((100-percent_offset)/100)));

echo("Percent Offset:", percent_offset);

layer_h = turbine_height/offset_slicing;

bot_r = blade_radius; //Bottom blade radius
//bot_r = 7.5;
top_r= blade_radius;

delta_r = top_r - bot_r;

stem_top_r = 7+2.6;
stem_bot_r = 8+2.6;

shaft_fit_r = 2.6; //Your connecting motor pin to turbine
shaft_fit_l = turbine_height;

translate([0,0,turbine_height])mirror([0,0,1])mirror([1,0,0])
difference() {
union() {

intersection() {

//Blades
linear_extrude(height=turbine_height, center = false, convexity = 10, twist = twist_angle*rotation_dir, slices = slicing)
  for(i=[0:num_blades-1])
    rotate((360*i)/num_blades)
      translate([0,-blade_thickness/2]) {
        if(apply_curvature != 1) { square([blade_radius, blade_thickness]); }
        else {
            if(rotation_dir == -1) {
                mirror([0,1,0])
                arc(blade_radius, blade_thickness, blade_arch);
            }
            else {arc(blade_radius, blade_thickness, blade_arch);}
      }}

//Non-linear extrusion

//Curve convex
//y = 1 - 1/exp(x)
exp_pow = 3;
end_point = 1 - 1/exp(exp_pow*1);

union() {
for (i=[0:offset_slicing-1]){
    if (i < slicing) {
        offset_r = delta_r*((1-1/exp(exp_pow*(i/slicing)))/end_point); //Normalised N
        offset_r_increment = delta_r*((1-1/exp(exp_pow*((i+1)/slicing)))/end_point); //Normalised N+1
        translate([0,0,i*layer_h])
        cylinder(layer_h, bot_r + offset_r, bot_r + offset_r_increment, center=false, $fn=100);
    }
    else {
        translate([0,0,i*layer_h])
        cylinder(layer_h, top_r, top_r, center=false, $fn=100);
    }

}}

/*
//Curve concave
//y = base^x - 1
//base = exp(1);
base = 3;
end_point = pow(base,1)-1;

union() {
for (i=[0:offset_slicing-1]){
    if (i < slicing) {
        offset_r = delta_r*((pow(base,i/slicing)-1)/end_point); //Normalised N
        offset_r_increment = delta_r*((pow(base,(i+1)/slicing)-1)/end_point);  //Normalised N+1
        translate([0,0,i*layer_h])
        cylinder(layer_h, bot_r + offset_r, bot_r + offset_r_increment, center=false, $fn=100);
    }
    else {
        translate([0,0,i*layer_h])
        cylinder(layer_h, top_r, top_r, center=false, $fn=100);
    }
    //echo("Layer: ", i);
}}*/

}

cylinder( turbine_height, stem_bot_r, stem_top_r,center=false, $fn=100); //Centre stem

}
translate([0,0,-2])knob();
cylinder( shaft_fit_l, shaft_fit_r, shaft_fit_r, center=false, $fn=100); } //Push fit cutout

//length and breath of inner arc
module arc(length, width, arch_height){
    //r = (l^2 + 4*b^2)/8*b
    radius = (pow(length,2) + 4*pow(arch_height,2))/(8*arch_height);
    echo(radius);
    translate([length/2,0,0])
    difference() {
    difference() {
        translate([0,-radius+arch_height,0])
            difference() {
                circle(r=radius+width,$fn=100);
                circle(r=(radius),$fn=100);
            }

        translate([-(radius+width),-(radius+width)*2,0,])
            square([(radius+width)*2,(radius+width)*2]);
    }
    union() {
        translate([-length,-arch_height])
            square([length/2,arch_height*2]);
        translate([length/2,-arch_height])
            square([length/2,arch_height*2]);
    }}
}

```


[User]
I'm looking to create a cup stacking organizer, kind of like those plastic ones you might see in a restaurant. It needs to be parametric so I can adjust it for different cup sizes.

Essentially, it needs three parts: a top ring to hold the top cup, a middle plate, and a bottom ring to hold the cup below it. The top ring should grip the *outside* of the upper cup and the bottom ring should grip the *inside* of the lower cup. The middle plate will have an outer diameter that extends past the bottom ring and an inner diameter smaller than the outer diameter of the bottom ring, forming a support.

I need to be able to specify the outer diameter of the cup, the inner diameter of the cup, and the overall height of the holder portion. The thickness of the rings and the height of the plate should be fixed values for now.

Could you generate the OpenSCAD code for this? I don't have any specific libraries in mind, so feel free to choose whatever is appropriate.

[Assistant]
Cup_Stack.scad:
```

// Input the diameter of your cup
cup_diameter = 83.5;

// Input the inner diameter of your cup (must be smaller than the cup diameter)
inner_cup_diameter = 72.0;

// Change the holder height, if necessary
holder_height = 10;

/* [Hidden] */

// Thickness of the walls
wall_thickness = 2;
// Height of the middle plate
plate_height = 2;

module ring(height,diameter,inner_diameter) {
  linear_extrude(height=height, center = true) {
    difference () {
      circle(d=diameter);
      circle(d=inner_diameter);
    };
  };
};

// Upper Holder
translate([0,0,(plate_height + holder_height) / 2]) {
  ring(holder_height, cup_diameter + wall_thickness, cup_diameter);
};

// Middle plate
ring(plate_height, cup_diameter + wall_thickness, inner_cup_diameter - wall_thickness);

// Inside Holder
translate([0,0,-(plate_height + holder_height) / 2]) {
  ring(holder_height, inner_cup_diameter, inner_cup_diameter - wall_thickness);
};

```


[User]
I'm looking for a parametric OpenSCAD design for a hose adapter, similar to the one I saw on Thingiverse (thing:3184173), but with the ability to control the overhang angle of the cone connecting the two hose diameters. I've attached the existing SCAD file that I modified, but I'd like you to generate a new, cleaner version with a few specific requirements.

Here's what I need:

*   **Two Cylindrical Nozzles:** The adapter needs to have two cylindrical sections, each with its own independently adjustable inner diameter (`nozzle1diameter`, `nozzle2diameter`) and height (`nozzle1height`, `nozzle2height`). The units are all millimeters.

*   **Wall Thickness:**  I want a `wallThickness` parameter that controls the thickness of *both* walls of each cylinder. So a wallThickness of 4 means 2mm thick walls.

*   **Cone Section:** The two nozzles should be connected by a conical section. The height of the cone should be automatically calculated based on the `overhangAngle` parameter. The cone should transition smoothly between the two diameters. I would like to specify this in degrees; a 45-degree overhang angle is a good default.

*   **Units:** Everything should be in millimeters.

*   **Smooth Cylinders:** Can you make sure the cylinders are smooth? I prefer $fn = 100 for the cylindrical sections.

*   **Nozzle Lips:** Can you also make the ends of each nozzle have a slight "lip" - a small inward-facing chamfer? This would be achieved by using a slightly different diameter for a short cylinder section on the ends of the nozzle cylinders, extending just slightly below each nozzle and the cone.

I think it should be possible to define the height of the cone section by using the given `overhangAngle` with the difference in nozzle diameters. I had to figure this part out when I adapted the existing code, but it'd be great if your solution could handle this part automatically. Also, please echo the cone height (z2) so I can confirm it's what I'm expecting.

I don't need any additional features, just these core elements, parameterized as described. I'm not requesting any external library dependencies.

[Assistant]
hosefit_overhang_angle.scad:
```
// 2021-05-15 Updated by Nico Fritschi to support overhang angle parameter. Also added description to parameters.

// 2018-10-29 OpenSCAD hose adapter by Dan Royer @ marginallyclever.com

// Inner Diameter in mm.
nozzle1diameter=145;  //[1:0.1:1000]
// Height in mm.
nozzle1height=23;  //[1:0.1:1000]

// Inner Diameter in mm.
nozzle2diameter=91;  //[1:0.1:1000]
// Height in mm.
nozzle2height=42;  //[1:0.1:1000]

// Thickness of both walls of the circle. So wallThickness=2 means that each individual wall is 1mm thick.
wallThickness=4; //[1:0.1:5]

overhangAngle=45; //[1:65]

// z2 = Height of the cone part
// Default was to use abs(nozzle1diameter-nozzle2diameter)
// -> This results in about 26 deg overhang. To achieve 45 deg
// overhang just divide by two.
// Here I want to calculte the height for a given overhang angle.
// This is what following formula does:
z2 = (abs(nozzle1diameter-nozzle2diameter) / 2) / tan(overhangAngle);

echo("Cone part height is ", z2);

// Nozzle 2 Height
z = nozzle1height+(nozzle2height)/2 + z2;

// z3 ? not used
z3 = (nozzle1height+nozzle2height)/2 + z2/2;

intersection() {
    // uncomment this to see a cross section of the shape.
    // translate([-250,0,-250]) { cube(500,500,500,false); }

    union() {
        // nozzle 1
        translate([0,0,nozzle1height/2]) {
            difference()
            {
                cylinder(h=nozzle1height,
                        d=(nozzle1diameter+wallThickness),
                        center=true,
                         $fn=100);
                cylinder(h=nozzle1height+0.01,
                        d=nozzle1diameter,
                        center=true,
                         $fn=100);
                translate([0,0,-(nozzle1height/2 +0.25)]) {
                    cylinder(h=1,
                             d =nozzle1diameter-1,
                             d1=nozzle1diameter+1,
                             center=false,
                             $fn=100);
                }
            }
        }

        // nozzle 2
        translate([0,0,z]) {
            difference()
            {
                cylinder(h=nozzle2height,
                        d=nozzle2diameter+wallThickness,
                        center=true,
                         $fn=100);
                cylinder(h=nozzle2height+0.01,
                        d=nozzle2diameter,
                        center=true,
                         $fn=100);
                translate([0,0,nozzle2height/2-0.75]) {
                    cylinder(h=1,
                             d =nozzle2diameter+1,
                             d1=nozzle2diameter-1,
                             center=false,
                             $fn=100);
                }
            }
        }

        // cone part
        translate([0,0,nozzle1height+z2/2])
        {
            difference()
            {
                cylinder(h=z2,
                        d1=nozzle1diameter+wallThickness,
                        d=nozzle2diameter+wallThickness,
                        center=true,
                         $fn=100);
                cylinder(h=z2+0.01,
                        d1=nozzle1diameter-1,
                        d=nozzle2diameter-1,
                        center=true,
                         $fn=100);

            }
        }
    }
}
```