- README.rst: nice images

- .gitignore

.gitignore

@@ -0,0 +1,4 @@
+.DS_Store
+*.xcf
+.*.swp
+design/THREAD_TABLE.csv

README.rst

@@ -17,13 +17,31 @@ Creating a thread is as simple as
 
 .. code-block:: OpenSCAD
 
-        thread("G1/2-ext", turns=10, higbee_arc=20);
+        thread("G1/2-ext", turns=10);
 
-to create a British Standard Pipe parallel external thread. Furthermore,
-threadlib allows for production tolerances by choosing thread dimensions well
-inside the ranges allowed by the norms.
+.. image:: docs/imgs/thread-G1o2-ext-10turns.png
+        :alt: bolt-in-nut logo
+
+to create a British Standard Pipe parallel external thread. 
 
 
+Why you may want to use threadlib
+==================================
+
+- really easy to use
+- creates nice threads
+- configurable higbee arc
+- creates working threads (clearances are left for production tolerances)
+- flexible:
+  - choose the $fn you need to fit the rest of your design
+  - let threadlib tell you the thread specs so you can do with them what *you*
+    want
+- extensible: Add your own threads
+- tried and tested in the real world: Um no, not yet. But with your help, it
+  will soon be.
+
+
+===========================
 Usage
 ===========================
 
@@ -31,20 +49,19 @@ To create a bolt (without head) with 5 turns of M4 thread:
 
 .. code-block:: OpenSCAD
 
-        bolt("M4", turns=5);
+        bolt("M4", turns=5, higbee_arc=30);
 
 .. image:: docs/imgs/bolt-M4.png
-        :width: 30%
         :alt: Bolt with M4 thread
 
-See these nice lead-in / lead-outs? Try a nut:
+See these nice lead-in / lead-outs? Try a nut (this time using the default
+argument for higbee_arc):
 
 .. code-block:: OpenSCAD
 
-        nut("M12x0.5", turns=10, Douter=40);
+        nut("M12x0.5", turns=10, Douter=16);
 
 .. image:: docs/imgs/nut-M12x0.5.png
-        :width: 30%
         :alt: M12x0.5 nut
 
 Note that for a nut you also have to specify an outer diameter. The inner
@@ -54,7 +71,10 @@ If you only need the threads alone:
 
 .. code-block:: OpenSCAD
 
-        thread("G2 1/2-ext", turns=5);
+        thread("G1/2-ext", turns=5);
+
+.. image:: docs/imgs/thread-G1o2-ext.png
+        :alt: G1/2 external thread
  
 Then, add the support you want. In the simplest case, a cylinder (which is what
 nut(...) uses):
@@ -68,18 +88,25 @@ nut(...) uses):
         translate([0, 0, -P / 2])
             cylinder(h=H, d=Dsupport, $fn=120);
 
+.. image:: docs/imgs/flexible.png
+        :alt: G1/2 bolt
+
 Here, we have used the function thread_specs(...) to look up the threads
 specifications - including the recommended diameter of the support structure.
 
 
+===========================
 List of supported threads
 ===========================
 
 Currently, threadlib knows these threads:
 
-- British Standard Pipe Parallel Threads G1/16 to G6
 - Metric threads (coarse, fine, and super-fine pitches) M0.25 to M600
+- British Standard Pipe Parallel Threads G1/16 to G6
+- PCO-1881 (PET-bottle thread)
 
+
+===========================
 Extensibility
 ===========================
 
@@ -102,9 +129,10 @@ accomplished and get the fame you deserve: Send in your tried and tested threads
 for addition to threadlib!
 
 
+===========================
 Change Log
 ===========================
 
-- 0.2: Metric threads
+- 0.2: Metric threads, PCO-1881
 - 0.1: Initial release supporting BSP parallel thread
 

docs/Makefile

@@ -1,19 +1,28 @@
 os = /usr/local/bin/openscad
 opts =
-imgs = imgs/bolt-M4.png imgs/nut-M12x0.5.png imgs/nutNbolt.png
+imgs = bolt-M4.png nut-M12x0.5.png nutNbolt.png thread-G1o2-ext.png thread-G1o2-ext-10turns.png flexible.png
 
 .PHONY: all
 all: $(imgs)
 
-imgs/bolt-M4.png: bolt.scad
-	$(os) $(opts) --D 'type="M4"' --camera=0.49,-0.26,1.55,74.6,0.0,78.9,20 --imgsize=2048,2048 -o $@ $<
+bolt-M4.png: bolt.scad
+	$(os) $(opts) --D 'type="M4"' --D 'turns=5' --D 'higbee_arc=30' --camera=0.49,-0.26,1.55,74.6,0.0,78.9,20 --imgsize=2048,2048 -o $@ $<
 
-imgs/nut-M12x0.5.png: nut.scad
-	$(os) $(opts) --D 'type="M12x0.5"' --D 'turns=10' --D 'Douter=16' --camera=-2.2,1.2,1.8,66,0,73,52 --imgsize=2048,2048 --projection=ortho -o $@ $<
+nut-M12x0.5.png: nut.scad
+	$(os) $(opts) --D 'type="M12x0.5"' --D 'turns=10' --D 'higbee_arc=20' --D 'Douter=16' --camera=-2.2,1.2,1.8,66,0,73,52 --imgsize=2048,2048 --projection=ortho -o $@ $<
 
-imgs/nutNbolt.png: nutNbolt.scad
+nutNbolt.png: nutNbolt.scad
 	$(os) $(opts) --camera=-0.24,1.19,4.24,83,0,326.9,40.3 --imgsize=2048,2048 --projection=ortho -o $@ $<
 
+thread-G1o2-ext-10turns.png: thread.scad
+	$(os) $(opts) --D 'type="G1/2-ext"' --D 'turns=10' --D 'higbee_arc=20' --camera=-0.7,-0.6,3.4,75,0,110,100 --imgsize=2048,2048 --projection=ortho -o $@ $<
+
+thread-G1o2-ext.png: thread.scad
+	$(os) $(opts) --D 'type="G1/2-ext"' --D 'turns=5' --D 'higbee_arc=20' --camera=-0.7,-0.6,3.4,75,0,110,57 --imgsize=2048,2048 --projection=ortho -o $@ $<
+
+flexible.png: flexible.scad
+	$(os) $(opts) --D 'type="G1/2-ext"' --D 'turns=5' --D 'higbee_arc=20' --camera=-0.7,-0.6,3.4,75,0,110,57 --imgsize=2048,2048 --projection=ortho -o $@ $<$
+
 .PHONY: clean
 clean:
-	rm imgs/*.png
+	rm *.png

docs/flexible.scad

@@ -0,0 +1,22 @@
+/*
+Create nice previews for documentation
+
+:Author: Adrian Schlatter
+:Date: 2019-04-13
+:License: 3-Clause BSD. See LICENSE.
+*/
+
+use <threadlib/threadlib.scad>
+
+type = "G1/2-ext";
+turns = 5;
+higbee_arc = 20;
+
+thread(type, turns, higbee_arc=higbee_arc);
+
+specs = thread_specs(type);
+P = specs[0]; Rrot = specs[1]; Dsupport = specs[2];
+section_profile = specs[3];
+H = (turns + 1) * P;
+translate([0, 0, -P / 2])
+    cylinder(h=H, d=Dsupport, $fn=120);

docs/thread.scad

@@ -0,0 +1,15 @@
+/*
+Create nice previews for documentation
+
+:Author: Adrian Schlatter
+:Date: 2019-04-13
+:License: 3-Clause BSD. See LICENSE.
+*/
+
+use <threadlib/threadlib.scad>
+
+type = "G1/2-ext";
+turns = 10;
+higbee_arc = 45;
+
+thread(type, turns, higbee_arc=higbee_arc);