tier-2-l-bracket / gemini-2.5-pro

  // ===============================================
  //                Parameters
  // ===============================================
  
  // --- Bracket Dimensions ---
  width     = 50;  // Width on X-axis
  depth     = 40;  // Horizontal flange depth on Y-axis
  height    = 40;  // Vertical flange height on Z-axis
  thickness = 3;   // Thickness of the flanges
  
  // --- M4 Countersunk Hole Dimensions ---
  hole_dia  = 4.5; // Through-hole diameter
  cs_dia    = 8;   // Countersink top diameter
  cs_depth  = 2;   // Countersink depth
  
  // --- Hole Positioning ---
  // X-coordinates for the two holes on each flange
  hole_pos_x_list = [10, width - 10]; 
  // Y-coordinate for holes on the horizontal flange (centerline)
  hole_pos_y = depth / 2;
  // Z-coordinate for holes on the vertical flange (centerline)
  hole_pos_z = height / 2;
  
  // --- Rendering Quality ---
  $fn = 64;
  
  
  // ===============================================
  //                  Model
  // ===============================================
  difference() {
      
      // 1. Create the main body of the L-bracket
      // The inner corner is at the origin [0, 0, 0]
      union() {
          // Horizontal flange, extending in +Y direction
          cube([width, depth, thickness]);
          
          // Vertical flange, extending in +Z direction
          cube([width, thickness, height]);
      }
      
      // 2. Create and subtract the countersunk holes
      
      // --- Holes on the horizontal flange ---
-     // The countersinks face downwards (towards -Z)
+     // The countersinks are on the top surface (z=thickness), facing downwards.
      for (x_pos = hole_pos_x_list) {
-         // Position the cutter at the top surface (z=thickness) and rotate it to face down
+         // Position the cutter at the top surface (z=thickness) and rotate it to point inwards (-Z)
          translate([x_pos, hole_pos_y, thickness])
          rotate(a=[180, 0, 0]) {
              // A small epsilon for clean subtraction
              eps = 0.1;
              // Countersink cone (frustum)
              cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
              // Through-hole
              cylinder(h = thickness + eps, d = hole_dia);
          }
      }
      
      // --- Holes on the vertical flange ---
-     // The countersinks face forwards (towards -Y)
+     // The countersinks are on the outer surface (y=0), facing inwards.
      for (x_pos = hole_pos_x_list) {
-         // Position the cutter at the front surface (y=thickness) and rotate it to face forward
-         translate([x_pos, thickness, hole_pos_z])
-         rotate(a=[90, 0, 0]) {
+         // [FIX] Position the cutter at the outer surface (y=0) and rotate it to point inwards (+Y).
+         // The original code placed it at the inner surface (y=thickness) and pointed it the wrong way,
+         // resulting in the countersink being on the inside corner as seen in the image.
+         translate([x_pos, 0, hole_pos_z])
+         rotate(a=[-90, 0, 0]) { // Rotate cutter's Z-axis to align with world's +Y axis
              // A small epsilon for clean subtraction
              eps = 0.1;
              // Countersink cone (frustum)
              cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
              // Through-hole
              cylinder(h = thickness + eps, d = hole_dia);
          }
      }
  }

  // ===============================================
  //                Parameters
  // ===============================================
  
  // --- Bracket Dimensions ---
  width     = 50;  // Width on X-axis
  depth     = 40;  // Horizontal flange depth on Y-axis
  height    = 40;  // Vertical flange height on Z-axis
  thickness = 3;   // Thickness of the flanges
  
  // --- M4 Countersunk Hole Dimensions ---
  hole_dia  = 4.5; // Through-hole diameter
  cs_dia    = 8;   // Countersink top diameter
  cs_depth  = 2;   // Countersink depth
  
  // --- Hole Positioning ---
  // X-coordinates for the two holes on each flange
  hole_pos_x_list = [10, width - 10]; 
  // Y-coordinate for holes on the horizontal flange (centerline)
  hole_pos_y = depth / 2;
  // Z-coordinate for holes on the vertical flange (centerline)
  hole_pos_z = height / 2;
  
  // --- Rendering Quality ---
  $fn = 64;
  
  
  // ===============================================
+ //           Cutter Module Definition
+ // ===============================================
+ 
+ // Module to create a reusable countersink cutter shape.
+ // The cutter is created along the Z-axis.
+ module countersink_cutter(length) {
+     // A small epsilon to ensure clean subtraction
+     eps = 0.1;
+     
+     // Countersink cone (frustum)
+     cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
+     
+     // Through-hole body
+     // This cylinder starts at the same base as the cone (z=0)
+     // to ensure they form a single solid for subtraction.
+     cylinder(h = length + eps, d = hole_dia);
+ }
+ 
+ 
+ // ===============================================
  //                  Model
  // ===============================================
+ 
  difference() {
      
      // 1. Create the main body of the L-bracket
-     // The inner corner is at the origin [0, 0, 0]
+     // The inner corner is at the origin [0, 0, 0].
      union() {
-         // Horizontal flange, extending in +Y direction
+         // Horizontal flange: Extends from origin in +Y direction.
+         // Occupies space: x=[0,width], y=[0,depth], z=[0,thickness]
          cube([width, depth, thickness]);
          
-         // Vertical flange, extending in +Z direction
+         // Vertical flange: Extends from origin in +Z direction.
+         // Occupies space: x=[0,width], y=[0,thickness], z=[0,height]
          cube([width, thickness, height]);
      }
      
      // 2. Create and subtract the countersunk holes
      
      // --- Holes on the horizontal flange ---
-     // The countersinks are on the top surface (z=thickness), facing downwards.
+     // Countersinks are on the outer (top) face, which is the plane z=thickness.
      for (x_pos = hole_pos_x_list) {
-         // Position the cutter at the top surface (z=thickness) and rotate it to point inwards (-Z)
+         // Move the cutter to the top surface and rotate it to point down (-Z).
          translate([x_pos, hole_pos_y, thickness])
          rotate(a=[180, 0, 0]) {
-             // A small epsilon for clean subtraction
-             eps = 0.1;
-             // Countersink cone (frustum)
-             cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
-             // Through-hole
-             cylinder(h = thickness + eps, d = hole_dia);
+             countersink_cutter(length = thickness);
          }
      }
      
-     // --- Holes on the vertical flange ---
-     // The countersinks are on the outer surface (y=0), facing inwards.
+     // --- Holes on the vertical flange (FIXED) ---
+     // Correction: The original model had the countersink on the inner face.
+     // The countersink must be on the outer face (the plane at y=0).
      for (x_pos = hole_pos_x_list) {
-         // [FIX] Position the cutter at the outer surface (y=0) and rotate it to point inwards (+Y).
-         // The original code placed it at the inner surface (y=thickness) and pointed it the wrong way,
-         // resulting in the countersink being on the inside corner as seen in the image.
+         // Move the cutter to the outer face (y=0) and rotate it to point inwards (+Y).
          translate([x_pos, 0, hole_pos_z])
-         rotate(a=[-90, 0, 0]) { // Rotate cutter's Z-axis to align with world's +Y axis
-             // A small epsilon for clean subtraction
-             eps = 0.1;
-             // Countersink cone (frustum)
-             cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
-             // Through-hole
-             cylinder(h = thickness + eps, d = hole_dia);
+         rotate(a=[-90, 0, 0]) {
+             countersink_cutter(length = thickness);
          }
      }
  }

  // ===============================================
  //                Parameters
  // ===============================================
  
  // --- Bracket Dimensions ---
  width     = 50;  // Width on X-axis
  depth     = 40;  // Horizontal flange depth on Y-axis
  height    = 40;  // Vertical flange height on Z-axis
  thickness = 3;   // Thickness of the flanges
  
  // --- M4 Countersunk Hole Dimensions ---
  hole_dia  = 4.5; // Through-hole diameter
  cs_dia    = 8;   // Countersink top diameter
  cs_depth  = 2;   // Countersink depth
  
  // --- Hole Positioning ---
  // X-coordinates for the two holes on each flange
  hole_pos_x_list = [10, width - 10]; 
  // Y-coordinate for holes on the horizontal flange (centerline)
  hole_pos_y = depth / 2;
  // Z-coordinate for holes on the vertical flange (centerline)
  hole_pos_z = height / 2;
  
  // --- Rendering Quality ---
  $fn = 64;
  
  
  // ===============================================
  //           Cutter Module Definition
  // ===============================================
  
  // Module to create a reusable countersink cutter shape.
- // The cutter is created along the Z-axis.
+ // The cutter is created pointing along the +Z axis.
  module countersink_cutter(length) {
      // A small epsilon to ensure clean subtraction
      eps = 0.1;
      
      // Countersink cone (frustum)
      cylinder(h = cs_depth, d1 = cs_dia, d2 = hole_dia);
      
      // Through-hole body
      // This cylinder starts at the same base as the cone (z=0)
-     // to ensure they form a single solid for subtraction.
+     // to form a single solid shape for subtraction.
      cylinder(h = length + eps, d = hole_dia);
  }
  
  
  // ===============================================
  //                  Model
  // ===============================================
  
  difference() {
      
      // 1. Create the main body of the L-bracket
-     // The inner corner is at the origin [0, 0, 0].
+     // The inner corner is placed at the origin [0, 0, 0].
      union() {
          // Horizontal flange: Extends from origin in +Y direction.
-         // Occupies space: x=[0,width], y=[0,depth], z=[0,thickness]
          cube([width, depth, thickness]);
          
          // Vertical flange: Extends from origin in +Z direction.
-         // Occupies space: x=[0,width], y=[0,thickness], z=[0,height]
          cube([width, thickness, height]);
      }
      
      // 2. Create and subtract the countersunk holes
      
-     // --- Holes on the horizontal flange ---
-     // Countersinks are on the outer (top) face, which is the plane z=thickness.
+     // Holes on the horizontal flange.
+     // The outer face is the top surface (z = thickness).
      for (x_pos = hole_pos_x_list) {
-         // Move the cutter to the top surface and rotate it to point down (-Z).
+         // Move cutter to the top surface and rotate to point down (-Z direction).
          translate([x_pos, hole_pos_y, thickness])
          rotate(a=[180, 0, 0]) {
              countersink_cutter(length = thickness);
          }
      }
      
-     // --- Holes on the vertical flange (FIXED) ---
-     // Correction: The original model had the countersink on the inner face.
-     // The countersink must be on the outer face (the plane at y=0).
+     // Holes on the vertical flange.
+     // The outer face is the front surface (y = 0).
      for (x_pos = hole_pos_x_list) {
-         // Move the cutter to the outer face (y=0) and rotate it to point inwards (+Y).
+         // Move cutter to the front surface and rotate to point inwards (+Y direction).
          translate([x_pos, 0, hole_pos_z])
          rotate(a=[-90, 0, 0]) {
              countersink_cutter(length = thickness);
          }
      }
  }