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Browse Source 
++++++++++++++++

- README.rst
- LICENSE
- License in code files
- nut and bolt to threadlib.scad (from test.scad)
- added feature to be able to use custom threads (table argument)
This commit is contained in:
Adrian Schlatter
2019-04-07 19:38:09 +02:00
parent 369e81f8ae
commit 24147eb7d0
6 changed files with 205 additions and 108 deletions
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26
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Copyright 2019 Adrian Schlatter
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice, this
list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
3. Neither the name of the copyright holder nor the names of its contributors
may be used to endorse or promote products derived from this software without
specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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threadlib
+++++++++++++++++++++++++++
threadlib is a library of standard threads for OpenSCAD.
In contrast to other thread libraries, it does not make you look up diameters
and pitches and maybe even thread-profiles in tables and norms: It has these
tables built in.
Creating a thread is as simple as
.. code-block:: OpenSCAD
thread("G1/2-ext", turns=10, higbee_arc=20);
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.
Usage
===========================
To create a bolt (without head) with 10 turns of G1-inch thread:
.. code-block:: OpenSCAD
bolt("G1", turns=10);
A nut:
.. code-block:: OpenSCAD
nut("G1", turns=10, Douter=40);
Note that for a nut you also have to specify an outer diameter. The inner
diameter is implicitly given by the thread designator ("G1" in this case).
If you only need the threads alone:
.. code-block:: OpenSCAD
thread("G2 1/2-ext", turns=5);
Then, add the support you want. In the simplest case, a cylinder (which is what
nut(...) uses):
.. code-block:: OpenSCAD
specs = thread_specs("G2 1/2-ext");
P = specs[0]; Rrot = specs[1]; Dsupport = specs[2];
section_profile = specs[3];
H = (5 + 1) * P;
translate([0, 0, -P / 2])
cylinder(h=H, d=Dsupport, $fn=120);
Here, we have used the function thread_specs(...) to look up the threads
specifications - including the recommended diameter of the support structure.
Extensibility
===========================
Don't find some of the threads you need for your project? Don't worry: You can
add your own:
.. code-block:: OpenSCAD
use <threadlib.scad>
MY_THREAD_TABLE = [
["special", [pitch, Rrot, Dsupport,
[[r0, z0], [r1, z1], ..., [rn, zn]]]]
];
thread("special", turns=15, table=MY_THREAD_TABLE);
Care to share? Safe others from repeating the valuable work you have already
accomplished and get the fame you deserve: Send in your tried and tested threads
for addition to threadlib!

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threadlib/THREAD_TABLE.scad
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/* This script is auto-generated - do not edit */ /* This script is auto-generated - do not edit
:License: 3-clause BSD. See LICENSE. */
THREAD_TABLE = [["G1/16-int", [0.907, 3.97888486, 7.921471162, [[0, 0.42515625], [0, -0.42515625], [-0.560841406, -0.12426807], [-0.560841406, 0.12426807]]]], THREAD_TABLE = [["G1/16-int", [0.907, 3.98, 7.92, [[0, 0.42515625], [0, -0.42515625], [-0.560841406, -0.12426807], [-0.560841406, 0.12426807
["G1/8-int", [0.907, 4.98138486, 9.926471162, [[0, 0.42515625], [0, -0.42515625], [-0.560841406, -0.12426807], [-0.560841406, 0.12426807]]]], ]]]],
["G1/4-int", [1.337, 6.743577241, 13.43364713, [[0, 0.62671875], [0, -0.62671875], [-0.826730937, -0.18318237], [-0.826730937, 0.18318237]]]], ["G1/8-int", [0.907, 4.98138486, 9.93, [[0, 0.42515625], [0, -0.42515625], [-0.560841406, -0.12426807], [-0.560841406, 0.12426807
["G3/8-int", [1.337, 8.496077241, 16.93864713, [[0, 0.62671875], [0, -0.62671875], [-0.826730937, -0.18318237], [-0.826730937, 0.18318237]]]], ]]]],
["G1/2-int", [1.814, 10.69426972, 21.31594232, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614]]]], ["G1/4-int", [1.337, 6.743577241, 13.43, [[0, 0.62671875], [0, -0.62671875], [-0.826730937, -0.18318237], [-0.826730937, 0.18318237
["G5/8-int", [1.814, 11.67226972, 23.27194232, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614]]]], ]]]],
["G3/4-int", [1.814, 13.43726972, 26.80194232, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614]]]], ["G3/8-int", [1.337, 8.496077241, 16.94, [[0, 0.62671875], [0, -0.62671875], [-0.826730937, -0.18318237], [-0.826730937, 0.18318237
["G7/8-int", [1.814, 15.31726972, 30.56194232, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614]]]], ]]]],
["G1-int", [2.309, 16.90027607, 33.70814489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G1/2-int", [1.814, 10.69426972, 21.32, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614
["G1 1/8-int", [2.309, 19.22427607, 38.35614489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G1 1/4-int", [2.309, 21.23077607, 42.36914489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G5/8-int", [1.814, 11.67226972, 23.27, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614
["G1 1/2-int", [2.309, 24.17727607, 48.26214489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G1 3/4-int", [2.309, 27.14877607, 54.20514489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G3/4-int", [1.814, 13.43726972, 26.80, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614
["G2-int", [2.309, 30.08277607, 60.07314489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G2 1/4-int", [2.309, 33.14002607, 66.18764489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G7/8-int", [1.814, 15.31726972, 30.56, [[0, 0.8503125], [0, -0.8503125], [-1.121682812, -0.24853614], [-1.121682812, 0.24853614
["G2 1/2-int", [2.309, 37.87702607, 75.66164489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G2 3/4-int", [2.309, 41.05202607, 82.01164489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G1-int", [2.309, 16.90027607, 33.71, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G3-int", [2.309, 44.22702607, 88.36164489, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G3 1/2-int", [2.309, 50.45002607, 100.8076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G1 1/8-int", [2.309, 19.22427607, 38.36, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G4-int", [2.309, 56.80002607, 113.5076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G4 1/2-int", [2.309, 63.15002607, 126.2076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G1 1/4-int", [2.309, 21.23077607, 42.37, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G5-int", [2.309, 69.50002607, 138.9076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G5 1/2-int", [2.309, 75.85002607, 151.6076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ["G1 1/2-int", [2.309, 24.17727607, 48.26, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G6-int", [2.309, 82.20002607, 164.3076449, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609]]]], ]]]],
["G1/16-ext", [0.907, 3.21661514, 6.469528838, [[0, -0.42515625], [0, 0.42515625], [0.578008291, 0.12426807], [0.578008291, -0.12426807]]]], ["G1 3/4-int", [2.309, 27.14877607, 54.21, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G1/8-ext", [0.907, 4.21911514, 8.474528838, [[0, -0.42515625], [0, 0.42515625], [0.578008291, 0.12426807], [0.578008291, -0.12426807]]]], ]]]],
["G1/4-ext", [1.337, 5.619922759, 11.29335287, [[0, -0.62671875], [0, 0.62671875], [0.852036477, 0.18318237], [0.852036477, -0.18318237]]]], ["G2-int", [2.309, 30.08277607, 60.07, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G3/8-ext", [1.337, 7.372422759, 14.79835287, [[0, -0.62671875], [0, 0.62671875], [0.852036477, 0.18318237], [0.852036477, -0.18318237]]]], ]]]],
["G1/2-ext", [1.814, 9.16973028, 18.41205768, [[0, -0.8503125], [0, 0.8503125], [1.156016582, 0.24853614], [1.156016582, -0.24853614]]]], ["G2 1/4-int", [2.309, 33.14002607, 66.19, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G5/8-ext", [1.814, 10.14773028, 20.36805768, [[0, -0.8503125], [0, 0.8503125], [1.156016582, 0.24853614], [1.156016582, -0.24853614]]]], ]]]],
["G3/4-ext", [1.814, 11.91273028, 23.89805768, [[0, -0.8503125], [0, 0.8503125], [1.156016582, 0.24853614], [1.156016582, -0.24853614]]]], ["G2 1/2-int", [2.309, 37.87702607, 75.66, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G7/8-ext", [1.814, 13.79273028, 27.65805768, [[0, -0.8503125], [0, 0.8503125], [1.156016582, 0.24853614], [1.156016582, -0.24853614]]]], ]]]],
["G1-ext", [2.309, 14.95972393, 30.01185511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G2 3/4-int", [2.309, 41.05202607, 82.01, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G1 1/8-ext", [2.309, 17.28372393, 34.65985511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G1 1/4-ext", [2.309, 19.29022393, 38.67285511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G3-int", [2.309, 44.22702607, 88.36, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G1 1/2-ext", [2.309, 22.23672393, 44.56585511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G1 3/4-ext", [2.309, 25.20822393, 50.50885511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G3 1/2-int", [2.309, 50.45002607, 100.81, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G2-ext", [2.309, 28.14222393, 56.37685511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G2 1/4-ext", [2.309, 31.19947393, 62.49135511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G4-int", [2.309, 56.80002607, 113.51, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G2 1/2-ext", [2.309, 35.93647393, 71.96535511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G2 3/4-ext", [2.309, 39.11147393, 78.31535511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G4 1/2-int", [2.309, 63.15002607, 126.21, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G3-ext", [2.309, 42.28647393, 84.66535511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G3 1/2-ext", [2.309, 48.50947393, 97.11135511, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G5-int", [2.309, 69.50002607, 138.91, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G4-ext", [2.309, 54.85947393, 109.8113551, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G4 1/2-ext", [2.309, 61.20947393, 122.5113551, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G5 1/2-int", [2.309, 75.85002607, 151.61, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
["G5-ext", [2.309, 67.55947393, 135.2113551, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ]]]],
["G5 1/2-ext", [2.309, 73.90947393, 147.9113551, [[0, -1.08234375], [0, 1.08234375], [1.471467634, 0.31635609], [1.471467634, -0.31635609]]]], ["G6-int", [2.309, 82.20002607, 164.31, [[0, 1.08234375], [0, -1.08234375], [-1.427764947, -0.31635609], [-1.427764947, 0.31635609
]]]], ]]]],
["G1/16-ext", [0.907, 3.21661514, 6.47, [[0, -0.42515625], [0, 0.42515625], [0.578008291, 0.12426807], [0.578008291, -0.12426807 ["G1/16-ext", [0.907, 3.21661514, 6.47, [[0, -0.42515625], [0, 0.42515625], [0.578008291, 0.12426807], [0.578008291, -0.12426807

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threadlib/autogenerate.awk
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@@ -1,4 +1,5 @@
BEGIN { print "/* This script is auto-generated - do not edit */" BEGIN { print "/* This script is auto-generated - do not edit"
print " :License: 3-clause BSD. See LICENSE. */"
printf "\nTHREAD_TABLE = [" } printf "\nTHREAD_TABLE = [" }
/^G/ { print "[\"" $1 "\", [" $2 ", " $3 ", " $4 ", [[" $5 ", " $6 "], [" $7 ", " $8 "], [" $9 ", " $10 "], [" $11 ", " $12 "]]]],"} /^G/ { print "[\"" $1 "\", [" $2 ", " $3 ", " $4 ", [[" $5 ", " $6 "], [" $7 ", " $8 "], [" $9 ", " $10 "], [" $11 ", " $12 "]]]],"}
END { print "];" } END { print "];" }

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threadlib/test.scad
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@@ -1,38 +1,16 @@
/* Test and demonstrate thread library */ /*
Test and demonstrate thread library
:Author: Adrian Schlatter
:Date: 2019-04-07
:License: 3-Clause BSD. See LICENSE.
*/
use <threadlib.scad> use <threadlib.scad>
module bolt(designator, turns, fn=120) {
union() {
specs = thread_specs(str(designator, "-ext"));
P = specs[0]; Dsupport = specs[2];
H = (turns + 1) * P;
thread(str(designator, "-ext"), turns=turns, higbee_arc=20, fn=fn);
translate([0, 0, -P / 2])
cylinder(h=H, d=Dsupport, $fn=fn);
};
};
module nut(designator, turns, fn=120) {
union() {
specs = thread_specs(str(designator, "-int"));
P = specs[0]; Dsupport = specs[2];
H = (turns + 1) * P;
rotate(180)
thread(str(designator, "-int"), turns=turns, higbee_arc=20, fn=fn);
translate([0, 0, -P / 2])
difference() {
cylinder(h=H, d=Dsupport * 1.1, $fn=fn);
translate([0, 0, -0.1])
cylinder(h=H+0.2, d=Dsupport, $fn=fn);
};
};
};
type = "G1"; type = "G1";
turns = 5; turns = 5;
Douter = thread_specs(str(type, "-int"))[2] * 1.2;
intersection() { intersection() {
color("Green") color("Green")
@@ -40,6 +18,6 @@ intersection() {
cube(200, 200, 200); cube(200, 200, 200);
union() { union() {
bolt(type, turns); bolt(type, turns);
nut(type, turns); nut(type, turns, Douter);
}; };
}; };

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threadlib/threadlib.scad
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@@ -1,45 +1,27 @@
/* /*
Britisch Standard Pipe Thread threadlib
++++++++++++++++++++++++++++++ +++++++++
British Standard Pipe Thread is based on a triangular profile. The angle between flanks Create threads easily.
is 55 deg (symmetrical). We use the following nomenclature:
- crest: The "summit" of a thread :Author: Adrian Schlatter
- valley: The lowest point in the valley of a thread :Date: 2019-04-07
- rcrest, rvalley: Radii of crest and groove, respectively :License: 3-Clause BSD. See LICENSE.
- rpitch = the mean radius of the original triangular profile
The crest and groove are both truncated by t/6. The radii at these flats are called
rmajor and rminor.
Note 1:
The specification requires that the flats are smoothed by circles that tangentially
match the flanks. We use a simpler version here: We create a triangular profile
and truncate the crests but not the grooves.
Note 2:
The specification requires allowances. This module creates threads with the ideal
rpitch for both external and internal threads (i.e., they just touch each other).
This is exactly at the edges of the given allowances and will not reliably work
in practice!
*/ */
use <thread_profile.scad> use <thread_profile.scad>
include <THREAD_TABLE.scad> include <THREAD_TABLE.scad>
function thread_specs(designator) = function thread_specs(designator, table=THREAD_TABLE) =
/* Returns thread specs of thread-type 'designator' as a vector of /* Returns thread specs of thread-type 'designator' as a vector of
[pitch, Rrotation, Dsupport, section_profile] */ [pitch, Rrotation, Dsupport, section_profile] */
THREAD_TABLE[search([designator], THREAD_TABLE, num_returns_per_match=1, table[search([designator], table, num_returns_per_match=1,
index_col_num=0)[0]][1]; index_col_num=0)[0]][1];
module thread(designator, turns, higbee_arc=45, fn=120) module thread(designator, turns, higbee_arc=20, fn=120, table=THREAD_TABLE)
{ {
specs = thread_specs(designator); specs = thread_specs(designator, table=table);
P = specs[0]; Rrotation = specs[1]; section_profile = specs[3]; P = specs[0]; Rrotation = specs[1]; section_profile = specs[3];
straight_thread( straight_thread(
section_profile=section_profile, section_profile=section_profile,
@@ -48,3 +30,31 @@ module thread(designator, turns, higbee_arc=45, fn=120)
turns=turns, turns=turns,
pitch=P); pitch=P);
} }
module bolt(designator, turns, higbee_arc=20, fn=120, table=THREAD_TABLE) {
union() {
specs = thread_specs(str(designator, "-ext"), table=table);
P = specs[0]; Dsupport = specs[2];
H = (turns + 1) * P;
thread(str(designator, "-ext"), turns=turns, higbee_arc=higbee_arc, fn=fn, table=table);
translate([0, 0, -P / 2])
cylinder(h=H, d=Dsupport, $fn=fn);
};
};
module nut(designator, turns, Douter, higbee_arc=20, fn=120, table=THREAD_TABLE) {
union() {
specs = thread_specs(str(designator, "-int"), table=table);
P = specs[0]; Dsupport = specs[2];
H = (turns + 1) * P;
rotate(180)
thread(str(designator, "-int"), turns=turns, higbee_arc=higbee_arc, fn=fn, table=table);
translate([0, 0, -P / 2])
difference() {
cylinder(h=H, d=Douter, $fn=fn);
translate([0, 0, -0.1])
cylinder(h=H+0.2, d=Dsupport, $fn=fn);
};
};
};