another: potentially even prettier pushfit arrangement

1 files changed, 26 insertions, 13 deletions

diff --git a/another.scad b/another.scad
index 6af68b6..4c4af5c 100644
--- a/another.scad
+++ b/another.scad
@@ -1,94 +1,95 @@
 draft=true;
 layer_height=0.2; extrusion_width=0.4;
 epsilon=0.01;
 $fs=0.0125;
 
 use <pushfittery.scad>;
 include <pushfit_data.scad>;
 
 module the_extruder(
  // motor properties
  gearbox_d = 36,
  mount_d = 28,					// the distance between opposite mounting holes
  mounthole_depth = 5,
  protrusion_d = 22, protrusion_h = 2.2,		// the dimensions of the protrusion on top of gearbox
  bore_d = 8, bore_l = 17.6,
  bore_dd = 7,
  // 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,
  // spring tensioner
  st_nut_d = 9, st_nut_h = 4,
  st_screw_d = 5,
  st_thickshell = 8*extrusion_width, st_thinshell = 4*extrusion_width,
 
  // screw it
  mount_screw_d = 3.1, mount_screw_l = 20,
  mount_screwhead_d=6, mount_screwhead_h=3,
  idler_screw_d = 3,
  idler_screwhead_d=6, idler_screwhead_h=3,
 
  pf = pushfit_embeddest,
  pf_shell = max(3*layer_height,3*extrusion_width),
+ pf_smooth = true,
 
  // 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=.4,
  idler_v_tolerance=.5,
  knob_bore_d_tolerance=.6,
  st_nut_h_tolerance=.2,
  st_nut_d_tolerance=.2,/* TODO: make it st_nut_w_tolerance */
  st_screw_d_tolerance=.3,
 
  what="lever",  // lever|body|knob|springpad|*
  left=false,
  vitamins = true,
  supports = false, bridges = true,
  tensioner = true,
  debug = false
 ) {
  fnd = 2*PI; fnr = 2*fnd;
 
  lever_shell = mount_screwhead_h+0.5;
  lever_thickness=max(spring_d+spring_d_clearance+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;
 
  filament_elevation=protrusion_h+pulley_elevation+teeth_elevation;
  ls_z = filament_elevation; // leverspace mid-z
  body_h = max(protrusion_h+bore_l,mount_screw_l-mounthole_depth/2+mount_screwhead_h,ls_z*2);
  ls_h = lever_thickness+lever_v_clearance; // leverspace height
 
  module mirrorleft() {
   mirror([left?0:1,0,0]) children();
  }
  module place_idler() {
   rotate([0,0,45])
   translate([(pulley_d+idler_d)/2,0,0])
   children();
  }
  module finger_indent(d=lever_thickness,depth/*=1*/,r/*=15*/) {
   if(depth) {
@@ -203,110 +204,122 @@ module the_extruder(
   }//translate
  }//lever module
  
  module body() {
   difference() {
    union() {
     cylinder(d=gearbox_d,h=body_h,$fn=fnd*gearbox_d);
     // finger and spring support
     fsw = gearbox_d-(gearbox_d-mount_d)/2-spring_lc;
     translate([-gearbox_d/2,0,0]) difference() {
      union() {
       hull() {
        translate([0,-longwing,ls_z])
        rotate([0,90,0])
        cylinder(d=lever_thickness,h=fsw,$fn=fnd*lever_thickness);
        hh=body_h-ls_z;
        translate([0,0,ls_z-lever_thickness/2])
        mirror([0,1,0]) cube(size=[fsw,longwing-hh+lever_thickness/sqrt(2),hh+lever_thickness/2]);
        hhh=ls_z;
        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]) {
       if(!tensioner) finger_indent(d=lever_thickness-1,r=15); else {
        mirror([0,0,1]) {
 	translate([0,0,st_thickshell])
 	hull() for(o=[0,spring_d]) translate([0,-o,0])
 	rotate([0,0,30])
 	cylinder(d=st_nut_d+st_nut_d_tolerance,h=st_nut_h+st_nut_h_tolerance,$fn=6);
 	translate([0,0,-1]) cylinder(d=st_screw_d+st_screw_d_tolerance,h=fsw+2,$fn=fnd*(st_screw_d+st_screw_d_tolerance));
 	bigd = spring_d+spring_d_clearance;
 	hf = (bigd-st_screw_d-st_screw_d_tolerance)/2;
 	translate([0,0,st_thickshell+st_nut_h+st_nut_h_tolerance+st_thinshell-epsilon])
 	cylinder(d1=st_screw_d+st_screw_d_tolerance,d2=bigd,
 	 h=hf+epsilon, $fn=fnd*bigd);
 	translate([0,0,st_thickshell+st_nut_h+st_nut_h_tolerance+st_thinshell+hf-epsilon])
 	cylinder(d=bigd,h=fsw+1,$fn=fnd*bigd);
        }
       }
      }
     } // translate
     
     // pushfit bracket
     translate([0,0,filament_elevation])
     rotate([0,0,45]) translate([pulley_d/2,0,0])
     rotate([-90,0,0])
     translate([0,0,mount_d/sqrt(2)/2+mount_screw_d-gearbox_d/2/*TODO:*/]) {
-     pfb2a = pf_d(pf)+2*pf_shell; pfba = pfb2a/2;
-     pfbd = pfb2a/cos(30);
-     pfbs = pfb2a*tan(30);
-     pfbl = pf_h(pf)+gearbox_d/2/*TODO:*/;
-     cylinder(d=pfbd,h=pfbl,$fn=6);
-     translate([-pfbs/2,0,0]) {
+     pfbl = pf_h(pf)+gearbox_d/2; //TODO:
+     if(pf_smooth) {
+      pfbd = pf_d(pf)+2*pf_shell;
       hull() {
-       translate([0,-pfba,0]) cube(size=[pfbs,pfb2a,pfbl]);
-       cube(size=[pfbs,filament_elevation,pfbl-filament_elevation+pfba]);
-       mirror([0,1,0])
-       cube(size=[pfbs,body_h-filament_elevation,pfbl-body_h+filament_elevation+pfba]);
-      }
-     }
-    }
+       cylinder(d=pfbd,h=pfbl,$fn=pfbd*fnd);
+       translate([-epsilon/2,0,0]) {
+        cube(size=[epsilon,filament_elevation,pfbl-filament_elevation+pfbd/2]);
+        mirror([0,1,0])
+        cube(size=[epsilon,body_h-filament_elevation,pfbl-body_h+filament_elevation+pfbd/2]);
+       }//translate
+      }//hull
+     }else{
+      pfb2a = pf_d(pf)+2*pf_shell; pfba = pfb2a/2;
+      pfbd = pfb2a/cos(30);
+      pfbs = pfb2a*tan(30);
+      cylinder(d=pfbd,h=pfbl,$fn=6);
+      translate([-pfbs/2,0,0]) {
+       hull() {
+        translate([0,-pfba,0]) cube(size=[pfbs,pfb2a,pfbl]);
+        cube(size=[pfbs,filament_elevation,pfbl-filament_elevation+pfba]);
+        mirror([0,1,0])
+        cube(size=[pfbs,body_h-filament_elevation,pfbl-body_h+filament_elevation+pfba]);
+       }//hull
+      }//translate*/
+     }//if(pf_smooth)
+    }//translate rotate translate rotate translate
    }//union (first child of difference)
 
    // protrusion
    translate([0,0,-1])
    cylinder(d=protrusion_d+protrusion_tolerance_h,h=protrusion_h+protrusion_tolerance_v+1,$fn=fnd*(protrusion_d+protrusion_tolerance_h));
    // mount screw holes
    for(zr=[0:90:359]) rotate([0,0,zr]) translate([mount_d/2,0,0]) {
     translate([0,0,mount_screw_l-mounthole_depth/2-(bridges?layer_height:-epsilon)])
     mirror([0,0,1])
     cylinder(d=mount_screw_d+mount_screw_d_tolerance,
              h=mount_screw_l-mounthole_depth/2+1,
 	     $fn=fnd*(mount_screw_d+mount_screw_d_tolerance));
     translate([0,0,mount_screw_l-mounthole_depth/2])
     cylinder(d=mount_screwhead_d,h=body_h+1,$fn=fnd*mount_screwhead_d);
    }//for
    // pushfit
    translate([0,0,filament_elevation])
    rotate([0,0,45]) translate([pulley_d/2,0,0])
    rotate([-90,0,0])
    translate([0,0,mount_d/sqrt(2)/2+mount_screw_d+epsilon])
    rotate([0,0,180]) {
     pushfit(pf);
     cylinder(d=filament_guide_d,h=gearbox_d,center=true,$fn=fnd*filament_guide_d);
     translate([0,-filament_guide_d/2/sqrt(2),0])
     rotate([0,0,45])
     cube(size=[filament_guide_d/2,filament_guide_d/2,gearbox_d],center=true);
    }//rotate translate rotate translate rotate translate
    // pulley
    cylinder(d=pulley_d+pulley_clearance,h=body_h+1,$fn=fnd*(pulley_d+pulley_clearance));
    // leverspace
    hull() for(x=[0,gearbox_d])
    rotate([0,0,45])
    translate([x,0,ls_z-ls_h/2])
    cylinder(d=idler_d+idler_clearance,h=ls_h,$fn=fnd*(idler_d+idler_clearance));
 
    // idler clearance
    a=cos(45)*(pulley_d+idler_d)/2;
    b=mount_d/2-a;
    x=sqrt(pow(a,2)+pow(b,2));
    translate([mount_d/2,0,ls_z])
    intersection() {
     r = x+idler_d/2+idler_clearance;
     cylinder(r=r,h=ls_h,center=true);
     translate([-r-1,0,-ls_h/2-1]) cube(size=[2*r+2,r+1,ls_h+2]);
    }
 
    // back side cutout
    a0 = asin((mount_screwhead_d+2*extrusion_width)/mount_d);