guitar

commit

9ca7ed1

parent

1e651c9

author

Neale Pickett

date

2026-03-01 19:40:07 -0700 MST

Working on the nut

1@@ -1,4 +1,4 @@
2-all: nut.tenor-guitar.3mf tuner-plate.3mf
3+all: nut.tenor-guitar.3mf nut.irish-bouzouki.3mf tuner-plate.3mf
4 
5 %.3mf: %.scad
6 	openscad -o $@ $<

 1@@ -1,27 +1,53 @@
 2-// Size of the nut
 3-size = [30, 9, 5];
 4+include <BOSL2/std.scad>
 5 
 6-// Strings you're putting on it, in mils (aka thous)
 7-string_gauges = [11, 16, 30, 40];
 8+size = [34, 4.2, 7.4]; // Size of the nut.
 9+depth = 1; // How deep the notches should be. You can always file down further!
10+stringsPerCourse = 2; // How many strings in a course? Western guitar has 1, mandolin has 2.
11+strings = [12, 12, 18, 18, 35, 35, 45, 45]; // String gauges (diameter in mils)
12+gap = 0.5; // Space between outer edge of strings in a course, percentage of spacing between strings
13+
14+numStrings = len(strings);
15+numCourses = numStrings / stringsPerCourse;
16+stringDiameters = strings * 25.4 / 1000;
17+
18+totalStringSize = sum(stringDiameters);
19+totalSpaceSize = size.x - totalStringSize;
20+
21+// Each course has padding space on each side, and gap space between strings.
22+// Each course gets totalSpaceSize/numCourses space:
23+
24+// 2*padding + (gap*padding*stringsPerCourse) = totalSpaceSize / numCourses
25+// padding * (2 + gap*stringsPerCourse) = totalSpaceSize / numCourses
26+padding = totalSpaceSize / numCourses / (2 + (gap*stringsPerCourse));
27+gapPadding = padding * gap;
28 
29 difference() {
30   $fn = 180; // 180 faces per complete circle is good enough for printing
31-  inch = 25.4; // mm per inch
32-  mil = inch / 1000; // mm per mil
33 
34+  // this is the part you'd buy from the supply store
35   intersection() {
36-    cube(size);
37-    rotate([0, 90, 0]) cylinder(h=size.x, r=size.y);
38+    cube(size, anchor=BACK+BOTTOM+LEFT);
39+    rotate([0, 90, 0]) cylinder(h=size.x, r=size.z);
40   }
41 
42-  strings = string_gauges * mil;
43-  spacing = size.x / len(strings);
44-  for (n = [0:len(strings)-1]) {
45-    d = strings[n];
46-    pos = [spacing * (n + 1/2), size.y, 0];
47-    translate(pos) rotate([5, 0, 0]) hull() {
48-      translate([0, 0, 0]) cylinder(h=size.z*2, d=d, center=true);
49-      translate([0, 10, 0]) cylinder(h=size.z*2, d=d, center=true);
50+  // this is the initial groove filing you'd pay extra for
51+  space = size.y / numStrings / 2;
52+  for (i = [0 : numStrings-1]) {
53+    d = stringDiameters[i];
54+    courseNo = floor(i / stringsPerCourse);
55+    courseItem = (stringsPerCourse > 0) ? (i % stringsPerCourse) : 0;
56+
57+    stringsOffset = sum([for (s = [0:i]) stringDiameters[i]]);
58+    xOffset = courseNo * (padding*2 + gap*stringsPerCourse) + stringsOffset;
59+    x = xOffset + padding + (courseItem * padding * gap);
60+
61+    translate([x, 0, size.z-depth+d/2]) {
62+      rotate([90-5, 0, 0]) {
63+        hull() {
64+          translate([0, 0, 0]) cylinder(h=size.z*2, d1=d*1.5, d2=d, center=true);
65+          translate([0, 2, 0]) cylinder(h=size.z*2, d=d*2, center=true);
66+        }
67+      }
68     }
69   }
70 }

 1@@ -2,13 +2,16 @@
 2     "parameterSets": {
 3         "tenor-guitar": {
 4             "size": "[30, 9, 5]",
 5-            "string_gauges": "[11, 16, 30, 40]"
 6+            "strings": "[11, 16, 30, 40]"
 7         },
 8         "tenor-guitar-heavy": {
 9             "size": "[30, 9, 5]",
10-            "string_gauges": "[14, 18, 29, 44]"
11+            "strings": "[14, 18, 29, 44]"
12+        },
13+        "irish-bouzouki": {
14+            "size": "[32.4, 4.2, 7.4]",
15+            "stringsPerCourse": "2",
16+            "strings": "[12, 12, 18, 18, 35, 35, 45, 45]"
17         }
18     }
19 }
20-            
21-