From 0041bc9c4acf9ad3a2ac90fd790faf03cf415a75 Mon Sep 17 00:00:00 2001
From: Kienan Stewart <kienan.stewart@burntworld.ca>
Date: Sun, 4 Jan 2026 09:32:11 -0500
Subject: [PATCH] Add inner coaster pattern - circle

---
 coaster.json | 27 +++++++++++++++++++++++++++
 coaster.scad | 22 +++++++++++++++++++++-
 2 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 coaster.json

diff --git a/coaster.json b/coaster.json
new file mode 100644
index 0000000..2f909be
--- /dev/null
+++ b/coaster.json
@@ -0,0 +1,27 @@
+{
+    "parameterSets": {
+        "design default values": {
+            "$fn": "180",
+            "Depth": "4",
+            "Diameter": "101.6",
+            "Inner_pattern": "c",
+            "Inner_pattern_depth": "1",
+            "Inner_pattern_width": "24.5",
+            "Inset": "true",
+            "Inset_depth": "1",
+            "Inset_width": "15"
+        },
+        "hdd-2.5-v1": {
+            "$fn": "180",
+            "Depth": "4",
+            "Diameter": "101.6",
+            "Inner_pattern": "c",
+            "Inner_pattern_depth": "1",
+            "Inner_pattern_width": "24.5",
+            "Inset": "true",
+            "Inset_depth": "1",
+            "Inset_width": "15"
+        }
+    },
+    "fileFormatVersion": "1"
+}
diff --git a/coaster.scad b/coaster.scad
index 9a8ddc3..ebf8553 100644
--- a/coaster.scad
+++ b/coaster.scad
@@ -5,13 +5,33 @@ Inset = false;
 Inset_depth = 4; // 0.1
 Inset_width = 5; // 0.1
 
+Inner_pattern = "n"; // [n: None, c: Circle]
+Inner_pattern_width = 5; // 0.1
+Inner_pattern_depth = 1; // 0.1
+
 $fn = 180; // 0.1
 
-rotate([0, 180, 0]) {
+module coaster_frame() {
 difference() {
 cylinder(h = Depth, d = Diameter); 
 if (Inset) {
     cylinder(h = Inset_depth, d = Diameter - 2*Inset_width);
 };
 };
+}
+
+module coaster_pattern() {
+  offset = Inset ? [0, 0, Inset_depth - Inner_pattern_depth] : [0, 0, -Inner_pattern_depth];
+  if (Inner_pattern == "c") {
+    translate(offset) {
+     #cylinder(h = Inner_pattern_depth, d = Inner_pattern_width);
+    }
+  }    
+}
+
+rotate([0, 180, 0]) {
+  union() {
+    coaster_frame();
+    coaster_pattern();
+  }
 };
\ No newline at end of file