1 files changed, 49 insertions, 6 deletions

diff --git a/another.scad b/another.scad
index 2be24e4..844dc3b 100644
--- a/another.scad
+++ b/another.scad
@@ -30,8 +30,12 @@ module the_extruder(
  knob_h = 10,
  knob_bore_l = 4,
  knob_indent_d = 4,
  knob_indents = 12,
+ // spring tensioner
+ st_nut_d = 9, st_nut_h = 4,
+ st_screw_d = 5,
+ st_shell = 4*extrusion_width,
 
  // screw it
  mount_screw_d = 3.1, mount_screw_l = 20,
  mount_screwhead_d=6, mount_screwhead_h=3,
@@ -49,12 +53,14 @@ module the_extruder(
  mount_screw_d_tolerance=.4,
  idler_v_tolerance=.5,
  knob_bore_d_tolerance=.6,
 
- what="lever",
+ what="lever",  // lever|body|knob|springpad|*
  left=false,
  vitamins = true,
- supports = false
+ supports = false,
+ tensioner = true,
+ debug = false
 ) {
  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;
@@ -196,10 +202,27 @@ module the_extruder(
        translate([0,0,0])
        mirror([0,1,0]) cube(size=[fsw,longwing-hhh+lever_thickness/sqrt(2),hhh+lever_thickness/2]);
       }
      }
-     translate([0,-longwing,ls_z]) rotate([0,-90,0])
-     finger_indent(d=lever_thickness-1,r=15);
+     translate([0,-longwing,ls_z]) rotate([0,-90,0]) {
+      if(!tensioner) finger_indent(d=lever_thickness-1,r=15); else {
+       if(debug) translate([0,-gearbox_d,-gearbox_d]) cube(size=[body_h/2+1,gearbox_d,gearbox_d+2]);
+       mirror([0,0,1]) {
+        translate([0,0,st_shell])
+        hull() for(o=[0,spring_d]) translate([0,-o,0])
+        rotate([0,0,30])
+        cylinder(d=st_nut_d,h=st_nut_h,$fn=6);
+        translate([0,0,-1]) cylinder(d=st_screw_d,h=fsw+2,$fn=st_screw_d*PI*2);
+        bigd = spring_d+spring_d_clearance;
+        hf = (bigd-st_screw_d)/2;
+        translate([0,0,st_shell+st_nut_h+st_shell-epsilon])
+        cylinder(d1=st_screw_d,d2=bigd,
+         h=hf+epsilon, $fn=bigd*PI*2 );
+        translate([0,0,st_shell+st_nut_h+st_shell+hf-epsilon])
+        cylinder(d=bigd,h=fsw+1,$fn=bigd*PI*2);
+       }
+      }
+     }
     } // translate
     
     // pushfit bracket
     translate([0,0,filament_elevation])
@@ -259,9 +282,9 @@ module the_extruder(
     mirror([0,1,0])
     cube(size=[gearbox_d,gearbox_d/2+1,lever_thickness+lever_v_clearance]);
    }
    //translate([-mount_d/2,-longwing,filament_elevation])
-   translate([mount_d/2,-longwing,filament_elevation])
+   if(!tensioner) translate([mount_d/2,-longwing,filament_elevation])
    rotate([0,-90,0]) difference() {
     cylinder(d=spring_d+spring_d_clearance,h=spring_lc+spring_dl,$fn=PI*spring_d);
     translate([0,0,spring_lc+spring_dl]) sphere(d=spring_d*3/4,$fn=PI*spring_d);
    }
@@ -294,8 +317,23 @@ module the_extruder(
   }
 
  }//body module
 
+ module springpad() {
+  smalld=st_screw_d+extrusion_width;
+  bigd = spring_d+spring_d_clearance/2;
+  hf = (bigd-smalld)/2;
+  translate([-gearbox_d/2+st_shell+st_nut_h+st_shell+smalld,-longwing,filament_elevation])
+  rotate([0,90,0]) difference() {
+   union() {
+    cylinder(d1=smalld,d2=bigd,h=hf,$fn=bigd*PI*2);
+    translate([0,0,hf-epsilon])
+    cylinder(d=bigd,h=hf*2,$fn=bigd*PI*2);
+   }
+   cylinder(d=st_screw_d,h=2*hf,$fn=st_screw_d*PI*2);
+  }
+ }
+
  module knob() {
   ch = knob_indent_d/2;
   translate([0,0,body_h+epsilon]) {
    mirror([0,0,1]) translate([0,0,-epsilon]) {
@@ -326,12 +364,17 @@ module the_extruder(
  mirrorleft()
  if(what=="lever") color("green",0.7) lever();
  else if(what=="body") color("yellow",0.7) body();
  else if(what=="knob") color("red",0.7) knob();
- else if(what=="both" || what=="*") {
+ else if(what=="springpad") color("blue",0.7) springpad();
+ else if(what=="both") {
+  color("green",0.7) lever();
+  color("yellow",0.7) body();
+ }else{
   color("green",0.7) lever();
   color("yellow",0.7) body();
   color("red",0.7) knob();
+  color("blue",0.7) springpad();
  }
 }
 
 the_extruder(what="both",left=false);