From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Tue, 4 Apr 2023 13:59:14 +0000 (+0100)
Subject: thread-internal-test: wip
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=commitdiff_plain;h=e16dfae4a483c801b2eb40209b9e7c93423504cf;p=reprap-play.git

thread-internal-test: wip

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---

diff --git a/thread-internal-test.scad b/thread-internal-test.scad
new file mode 100644
index 0000000..a1fb5b7
--- /dev/null
+++ b/thread-internal-test.scad
@@ -0,0 +1,46 @@
+// -*- C -*-
+
+include <threads.scad>
+include <utils.scad>
+
+// https://en.wikipedia.org/wiki/ISO_metric_screw_thread
+
+// M6
+thread_nom = 6;
+thread_pitch = 1.00;
+thread_act = thread_nom - 0.300;
+head_size = 10;
+
+thread_len = 12.5;
+base_th = 1.5;
+base_sz = [40, head_size];
+
+$test = true;
+
+// calculated
+
+base_dia = head_size / cos(30);
+
+module ScrewThread(){
+  translate([0, 0, -0.1])
+    render()
+    metric_thread(diameter=thread_act, pitch=thread_pitch,
+		  leadin=1, internal=true,
+		  test=$test, length=thread_len + 0.1);
+}
+
+module TestThread(){
+  difference(){
+    union(){
+      linextr(-base_th, 0)
+	square(center=true, base_sz);
+
+      linextr(-base_th, thread_len - 0.1)
+	circle(r= base_dia/2, $fn=6);
+    }
+
+    ScrewThread();
+  }
+}
+
+TestThread();