Here is a refined, finalized metric thread library for OpenSCAD. It's minimal/simple, and has no external dependencies e.g. no deps. on BOSL/BOSL2. It's optimized for rendering in F5/preview mode. It consists of approx. 400 lines of code which includes extensive comments (without comments probably 300 lines of code). You would use it like this:

diameter = 3.0;
pitch = 0.5;
fine = 2; // Set to one to use default segment granularity.
segments = metric_thread_segments(diameter) * fine;

union() {
length = 4.0;
start = -0.3;
external_metric_thread(diameter, pitch, length, z_start= start,
bottom_lead_in= true, top_lead_in= true,
top_relief= true, fn= segments);
translate([0, 0, start]) {
cylinder(r= metric_thread_minor_radius(diameter, pitch, false),
h= length, center= false, $fn= segments); }
}

union() {
length = 2.8;
start = -1.7;
internal_metric_thread(diameter, pitch, length, z_start= start,
bottom_chamfer= true, top_chamfer= true,
fn= segments);
translate([0, 0, length/2 + start]) {
difference() {
cube([diameter2, diameter2, length], center= true);
cylinder(r= metric_thread_major_radius(diameter, pitch, true),
h= length * 1.125, center= true, $fn= segments);
}
}}

The above would produce something that looks like this:

[threads.png]

The thread library resides here, and it consists of a single file: https://sourceforge.net/p/nl10/code/HEAD/tree/scad/common/metric-threads.scad

I have a little Youtube presentation/introduction of this code: https://www.youtube.com/watch?v=3nc-cSm7oQk

The reason why I'm presenting this is because I am gradually migrating over from OpenSCAD to CadQuery and I want to leave behind some of the most useful stuff I wrote. It will be forgotten about unless I introduce it now.

Thanks and good luck. Happy coding.

Sent with Proton Mail secure email.

https://www.thingiverse.com/thing:2989174 😉

From: neri-engineering via Discuss discuss@lists.openscad.org
Sent: 26 January 2024 21:14:54
To: OpenSCAD general discussion Mailing-list
Cc: neri-engineering
Subject: [OpenSCAD] Lightweight Metric Thread Library

Here is a refined, finalized metric thread library for OpenSCAD.  It's minimal/simple, and has no external dependencies e.g. no deps. on BOSL/BOSL2.  It's optimized for rendering in F5/preview mode.  It consists of approx. 400 lines of code which includes extensive comments (without comments probably 300 lines of code).  You would use it like this:

diameter =  3.0;
pitch    =  0.5;
fine    =  2; // Set to one to use default segment granularity.
segments =  metric_thread_segments(diameter) * fine;

union() {
length =  4.0;
start  = -0.3;
external_metric_thread(diameter, pitch, length, z_start= start,
bottom_lead_in= true, top_lead_in= true,
top_relief= true, fn= segments);
translate([0, 0, start]) {
cylinder(r= metric_thread_minor_radius(diameter, pitch, false),
h= length, center= false, $fn= segments); }
}

union() {
length =  2.8;
start  = -1.7;
internal_metric_thread(diameter, pitch, length, z_start= start,
bottom_chamfer= true, top_chamfer= true,
fn= segments);
translate([0, 0, length/2 + start]) {
difference() {
cube([diameter2, diameter2, length], center= true);
cylinder(r= metric_thread_major_radius(diameter, pitch, true),
h= length * 1.125, center= true, $fn= segments);
}
}
}

The above would produce something that looks like this:

[threads.png]

The thread library resides here, and it consists of a single file: https://sourceforge.net/p/nl10/code/HEAD/tree/scad/common/metric-threads.scad

I have a little Youtube presentation/introduction of this code: https://www.youtube.com/watch?v=3nc-cSm7oQk

The reason why I'm presenting this is because I am gradually migrating over from OpenSCAD to CadQuery and I want to leave behind some of the most useful stuff I wrote.  It will be forgotten about unless I introduce it now.

Thanks and good luck.  Happy coding.

Sent with Proton Mailhttps://proton.me/ secure email.