knob

2 files changed, 40 insertions, 2 deletions

diff --git a/Makefile b/Makefile
index 9444a03..31135cb 100644
--- a/Makefile
+++ b/Makefile
@@ -2,21 +2,23 @@
 
 OPENSCAD_APP?=/Applications/OpenSCAD.app
 OPENSCAD_BIN?=${OPENSCAD_APP}/Contents/MacOS/OpenSCAD
 OPENSCAD_FLAGS=-D draft=false
 
 default:
 	@echo "And?"
 
 clean:
 	rm -f *.stl *.gcode
 
 stl-another-%:
-	$(MAKE) another-$*-{body,lever}.stl
+	$(MAKE) another-$*-{body,lever,knob}.stl
 
 another-%-body.stl: another-%.scad another.scad
 	$(OPENSCAD_BIN) $(OPENSCAD_FLAGS) -D 'what="body"' -o "$@" "$<"
 another-%-lever.stl: another-%.scad another.scad
 	$(OPENSCAD_BIN) $(OPENSCAD_FLAGS) -D 'what="lever"' -o "$@" "$<"
+another-%-knob.stl: another-%.scad another.scad
+	$(OPENSCAD_BIN) $(OPENSCAD_FLAGS) -D 'what="knob"' -o "$@" "$<"
 
 %.stl: %.scad
 	${OPENSCAD_BIN} ${OPENSCAD_FLAGS} -o "$@" "$<"
diff --git a/another.scad b/another.scad
index fa60676..9f42f46 100644
--- a/another.scad
+++ b/another.scad
@@ -23,39 +23,45 @@ module the_extruder(
  // pulley properties
  pulley_d = 11.5, pulley_h=10,
  pulley_elevation = 1,				// pulley elevation above the protrusion
  teeth_elevation = 7.5,				// distance from the bottom of the pulley to its teeth
  // idler properties
  idler_d = 9.5, idler_h = 4, idler_id = 3,	// idler dimensions: outer and inner diameters and height
  // spring properties
  spring_d = 10, spring_lc = 9.6,		// spring diameter and compressed length
  // filament path properties
  filament_d = 1.75,
  filament_path_d = 2,
  filament_guide_d = 4,				// PTFE filament guide diameter
+ // knob properties
+ knob_h = 10,
+ knob_bore_l = 4,
+ knob_indent_d = 4,
+ knob_indents = 12,
 
  // screw it
  mount_screw_d = 3, mount_screw_l = 20,
  mount_screwhead_d=6, mount_screwhead_h=3,
 
  // empty spaces
  idler_travel = 3,				// how far should idler travel when pressed
  idler_clearance=1,
  pulley_clearance=2,
  lever_v_clearance=.7,				// vertical clearance for the lever
  spring_d_clearance=1,
  protrusion_tolerance_h=.5,			// horizontal tolerance for the motor protrusion
  protrusion_tolerance_v=.5,			// vertical tolerance for the motor protrusion
  mount_screw_d_tolerance=.5,
  idler_v_tolerance=.5,
+ knob_bore_d_tolerance=.6,
 
  what="lever",
  left=false,
  vitamins = true
 ) {
  lever_shell = mount_screwhead_h+0.5;
  lever_thickness=max(spring_d+layer_height*8,idler_h+idler_v_tolerance+2*lever_shell);
  lsd = idler_d-idler_clearance*2;
  longwing=gearbox_d/2+spring_d/2+lsd/2;
  h_ = (pulley_d+idler_d)/(2*sqrt(2));
  ri = sqrt( pow(h_,2) + pow(mount_d/2-h_,2) );
  spring_dl = idler_travel*longwing/ri;
@@ -283,23 +289,53 @@ module the_extruder(
    if(false) { // parallel
     for(y=[-gearbox_d:4:gearbox_d])
      translate([0,y-extrusion_width/2,0])
      cube(size=[gearbox_d,extrusion_width,body_h]);
    }else{ // radial
     for(zr=[-65:(65+50)/7:50])
      rotate([0,0,zr]) translate([0,-extrusion_width/2,0])
      cube(size=[gearbox_d,extrusion_width,body_h]);
    }
   }
 
  }//body module
+
+ module knob() {
+  ch = knob_indent_d/2;
+  translate([0,0,body_h+epsilon]) {
+   mirror([0,0,1]) translate([0,0,-epsilon]) {
+    difference() {
+     cylinder(d=pulley_d,h=knob_bore_l,$fn=pulley_d*PI*2);
+     translate([0,0,-1]) difference() {
+      cylinder(d=bore_d+knob_bore_d_tolerance,h=knob_bore_l+2);
+      translate([-bore_d/2-1,bore_dd-bore_d/2+knob_bore_d_tolerance/2,-1])
+      cube([bore_d+2,bore_d/2,knob_bore_l+4]);
+     }
+    }
+   }
+   difference() {
+    union() {
+     cylinder(d1=gearbox_d-2*ch,d2=gearbox_d,h=ch+epsilon,$fn=PI*gearbox_d*2);
+     translate([0,0,ch])
+     cylinder(d=gearbox_d,h=knob_h-2*ch+epsilon,$fn=PI*gearbox_d*2);
+     translate([0,0,knob_h-ch])
+     cylinder(d1=gearbox_d,d2=gearbox_d-2*ch,h=ch,$fn=PI*gearbox_d*2);
+    }
+    for(a=[0:360/knob_indents:359]) rotate([0,0,a])
+     translate([0,gearbox_d/2,-1])
+     cylinder(d=knob_indent_d,h=knob_h+2,$fn=knob_indent_d*PI*2);
+   }
+  }
+ }//knob module
  
  mirrorleft()
  if(what=="lever") color("green",0.7) lever();
  else if(what=="body") color("yellow",0.7) body();
- else if(what=="both") {
+ else if(what=="knob") color("red",0.7) knob();
+ else if(what=="both" || what=="*") {
   color("green",0.7) lever();
   color("yellow",0.7) body();
+  color("red",0.7) knob();
  }
 }
 
 the_extruder(what="both",left=false);