Added pulleys, bom item listing

assembly.scad

@@ -28,10 +28,12 @@ module corners() {
 }
 
 module rails() {
-  frame_offset = frame_size / 2 + corner_size / 2;
+  frame_offset = yrail_offset;
   colorize(stock_color)
   {
     for (xpos = [frame_offset, xsize - frame_offset]) {
+      rail_len = ysize - corner_offset * 2;
+      bom_item(printable=false, label = str("steel_bar(d=8mm, len=", rail_len, "mm)"));
       translate([xpos,
 		 frame_size / 2 + wall_thickness])
 	rotate([-90, 0, 0])
@@ -41,13 +43,15 @@ module rails() {
 }
 
 module ysled_rails() {
-  frame_offset = frame_size + corner_size / 2;
   yoff = ysled_rail_spacing / 2;
+  rail_len = xsize - frame_size - yrail_offset * 2;
   colorize(stock_color)
-  for (ypos = [-yoff, yoff])
+  for (ypos = [-yoff, yoff]) {
+    bom_item(printable=false, label = str("steel_bar(d=8mm, len=", rail_len, "mm)"));
     translate([frame_size / 2, ypos, 0])
       rotate([0, 90, 0])
-      cylinder(d = rail_diam, h = xsize - frame_size * 2 - corner_size);
+      cylinder(d = rail_diam, h = rail_len);
+  }
 }
 
 
@@ -59,15 +63,17 @@ module xsled() {
 }
 
 module moving_parts(xpos = cur_xpos, ypos = cur_ypos) {
-  translate([frame_size / 2 + corner_size / 2,
+  translate([yrail_offset, cur_ypos, 0])
-	     cur_ypos, 0]) {
+    ysled_slider(spread = sled_ysize);
-    ysled_slider(spread = sled_ysize, associated_parts = true);
+  
-    translate([xsize - frame_size - corner_size, 0, 0])
+  translate([xsize - yrail_offset, cur_ypos, 0])
-      rotate([0, 180, 0]) 
+    rotate([0, 180, 0]) 
-      ysled_slider(spread = sled_ysize, associated_parts = true);
+    ysled_slider(spread = sled_ysize);
-    ysled_rails();
+  
+  translate([yrail_offset, cur_ypos, 0])
+    if($preview) ysled_rails();
     
-  }
+  
   translate([cur_xpos, cur_ypos, 0]) {
    // xsled();
     xsled2();
@@ -75,8 +81,8 @@ module moving_parts(xpos = cur_xpos, ypos = cur_ypos) {
 }
 
 union() {
-  frame();
+  if($preview) frame();
-  rails();
+  if($preview) rails();
   corners();
   moving_parts();
 }

lib.scad

@@ -0,0 +1,5 @@
+module bom_item(printable = true, label = "") {
+    print_label = printable ? " print " : " stock ";
+    item_label = label == "" ? parent_module(1) : label;
+    echo(str("BOM:", print_label, item_label));
+}

parts.scad

@@ -1,4 +1,5 @@
 include <units.inc>;
+include <lib.scad>;
 include <constants.scad>;
 include <stock_parts.scad>;
 
@@ -11,6 +12,8 @@ corner_size=30;
 // will be $L.
 corner_offset = frame_size / 2 + wall_thickness;
 rail_diam = 8;
+// distance between centerline of rail and centerline of frame Y tube.
+yrail_offset = (frame_size + corner_size / 2) / 2;
 
 ysled_extralen = frame_size; // on each end
 
@@ -23,6 +26,7 @@ ysled_rail_spacing = (sled_ysize);
 
 // Generates bar of length $l, centered on origin extending in +Z
 module tslot(l) {
+  bom_item(printable=false, label = str("tslot(", l, "mm)"));
   colorize(stock_color) {
     translate([-frame_size/2, -frame_size/2, 0])
       cube([frame_size, frame_size, l]);
@@ -60,23 +64,28 @@ module rail_holder(in_x) {
   ldim = frame_size/2 + corner_size;
   tube_offset = (corner_size) / 2 + wall_thickness;
   tube_rotation = in_x ? 90 : 0;
+
+  translated_rail_offset = yrail_offset - frame_size / 2;
+
   translate([frame_size/2, frame_size/2, -frame_size/2]) {
     difference() {
       linear_extrude(frame_size)
-	polygon(points = [[wall_thickness, wall_thickness],
+	      polygon(points = [[wall_thickness, wall_thickness],
-			  [wall_thickness, corner_size],
+			    [wall_thickness, corner_size],
-			  [corner_size, wall_thickness]]);
+		      [corner_size, wall_thickness]]);
-      translate([corner_size / 2, corner_size/2, frame_size/2])
+
-	rotate([tube_rotation -90, tube_rotation, 0])
+      translate([translated_rail_offset, translated_rail_offset, frame_size/2])
-	translate([0, 0, -corner_size])
+        rotate([tube_rotation -90, tube_rotation, 0])
-	cylinder(d = rail_diam, corner_size * 2);
+        translate([0, 0, -corner_size])
+        cylinder(d = rail_diam, corner_size * 4);
 		
     }
   }
 }
 
 // centered on 
-module ysled_slider(spread, associated_parts = false) {
+module ysled_slider(spread, associated_parts = $preview) {
+  bom_item(label = str("ysled_slider(", spread, ")"));
   sled_len = spread + frame_size;
   sled_height = frame_size;
   
@@ -145,35 +154,48 @@ module nema17_housing() {
 }
 
 module flcorner() {
+  bom_item();
   rotate([0, 0, 0]) {
     corner_base();
     rail_holder(false);
   }
   translate([(corner_size-wall_thickness)/2, 0, 0])
     nema17_housing();
+  
+  if($preview)
   translate([(corner_size - wall_thickness) / 2,
 	     -nema17_face/2 - frame_size/2 - wall_thickness,
 	     frame_size/2]) {
     nema17();
+    translate([0, 0, 2]) {
+      pulley(16,6,1,7);
+    }
   }
     
 }
 
 module frcorner() {
+  bom_item();
   rotate([0, 0, 90]) {
     corner_base();
     rail_holder(true);
   }
   translate([-(corner_size-wall_thickness)/2, 0, 0])
     nema17_housing();
+  
+  if($preview)
   translate([-(corner_size - wall_thickness) / 2,
 	     -nema17_face/2 - frame_size/2 - wall_thickness,
 	     frame_size/2]) {
     nema17();
+    translate([0,0,2]) {
+      pulley(16, 1, 6, 7);
+    }
   }
 }
 
 module blcorner() {
+  bom_item();
   rotate([0, 0, 270]) {
     corner_base();
     rail_holder(true);
@@ -181,6 +203,7 @@ module blcorner() {
 }
 
 module brcorner() {
+  bom_item();
   rotate([0, 0, 180]) {
     corner_base();
     rail_holder(false);
@@ -212,17 +235,20 @@ module xsled_slider() {
     }
     
   }
+  if($preview)
   rotate([0, 90, 0])
     bushing();
 }
 
 module sled_cornera() {
+  bom_item();
   corner_base();
   translate([-frame_size/2 - wall_thickness, 0, -frame_size])
     xsled_slider();
 }
 
 module sled_cornerb() {
+  bom_item();
   corner_base();
   rotate([0,0,90])
   translate([-frame_size/2 - wall_thickness, 0, -frame_size])
@@ -270,7 +296,7 @@ module xsled_frame() {
 }
 
 module xsled2() {
-
+  bom_item();
 
   tab_len = bushing_len * 2;
   tab_thickness = bushing_od + wall_thickness * 2;
@@ -368,4 +394,5 @@ module xsled2() {
   }
 }
 // render()
-//xsled2();
+// xsled2();
+

stock_parts.scad

@@ -1,3 +1,6 @@
+include <MCAD/math.scad>;
+include <lib.scad>;
+
 stock_color = "#aaa4";
 
 bushing_od = 12;
@@ -15,6 +18,7 @@ module colorize(colorname) {
 }
 
 module bushing() {
+  bom_item(printable=false, label="Bushing");
   colorize(stock_color) render() {
     difference() {
       cylinder(d = bushing_od, h = bushing_len);
@@ -26,6 +30,7 @@ module bushing() {
 
 // located with the shaft in +z, face on the XY plane 
 module nema17(depth = 23.5) {
+  bom_item(printable=false, label="NEMA-17 stepper motor");
   face = 42.3;
   screw_pitch = 31 / 2;
   color(stock_color)
@@ -51,3 +56,65 @@ module nema17(depth = 23.5) {
   }
 
 }
+
+// belts and pulleys
+belt_pitch = 2; // 2mm tooth width for GT2 = 2mm pitch
+belt_width = 6;
+belt_thickness = 3;
+tooth_height = 2;
+
+module pulley(teeth, lrim, urim, belt_width, shaft=5, toothed=true) {
+  bom_item(printable=false, label=str(
+    toothed ? "pulley(" : "idler(",
+    "teeth=", teeth, ", ",
+    "flange1=", min(lrim, urim), "mm, ",
+    "flange2=", max(lrim, urim), "mm, ",
+    "channel=", belt_width, "mm, ",
+    "shaft=", shaft, "mm",
+    ")"
+  ));
+  inner_rad = belt_pitch * teeth / TAU;
+  outer_rad = inner_rad + belt_thickness;
+  minor_rad = inner_rad - tooth_height;
+  mid_rad = inner_rad - tooth_height / 2;
+
+  dtheta = 180 / teeth;
+
+  tooth_points = [
+    for (i = [1:1:teeth])
+    let (theta = i * 360 / teeth)
+    each [
+      [sin(theta) * minor_rad, cos(theta) * minor_rad],
+      [sin(theta) * inner_rad, cos(theta) * inner_rad],
+      [sin(theta + dtheta) * inner_rad, cos(theta + dtheta) * inner_rad],
+      [sin(theta + dtheta) * minor_rad, cos(theta + dtheta) * minor_rad]
+    ]
+  ];
+
+  //echo([each [0:1:teeth]]);
+
+  //echo(tooth_points);
+
+  colorize(stock_color)
+  render()
+  difference() {
+    union() {
+      cylinder(r=outer_rad, h=lrim);
+      translate([0,0,lrim])
+      if (toothed) {
+        linear_extrude(belt_width)
+        polygon(tooth_points, convexity = teeth * 2 + 4);
+      } else {
+        cylinder(r = minor_rad, h = belt_width);
+      }
+
+      translate([0,0,lrim + belt_width])
+      cylinder(r=outer_rad, h=urim);
+    }
+
+    translate([0,0,-1])
+    cylinder(d=shaft, h=belt_width + lrim + urim + 2);
+  }
+}
+
+//!pulley(12, 6, 2, toothed=false);