adjustments to screw mount depth

1 files changed, 11 insertions, 4 deletions

diff --git a/another.scad b/another.scad
index 6afa9ef..6ef7299 100644
--- a/another.scad
+++ b/another.scad
@@ -1,134 +1,141 @@
 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,
+ mounthole_min_depth = 3, mounthole_max_depth = 4,
          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
  filament_offset = (8.25-(3.0+3.5)/2) - 11.5/2 + 1.75/2,
  // 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_d_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=.5,
 
+ min_z_shell = 4*layer_height,                  // the very minimal shell thickness along z-axis.
+
  what="lever",  // lever|body|knob|springpad|*
  left=false,
  vitamins = true,
  supports = false, bridges = true,
  tensioner = true,
  debug = false
 ) {
  fnd = 2*PI; fnr = 2*fnd;
 
  idler_filament_offset = filament_path_d/2; // -filament_offset;
  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;
 
+ mount_min_depth = mounthole_min_depth ? mounthole_min_depth : mounthole_depth-1;
+ mount_max_depth = mounthole_max_depth ? mounthole_max_depth : mounthole_depth+1;
  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
+ mount_depth = mount_screw_l - (ls_z+ls_h/2+min_z_shell);
+ body_h = max(protrusion_h+bore_l,mount_screw_l-mount_depth+mount_screwhead_h+min_z_shell,ls_z*2);
+ echo("mount depth",mount_depth);
 
  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) {
    hh = (-4*pow(depth,2)+pow(d,2))/(8*depth);
    rr = depth+hh;
    translate([0,0,hh]) sphere(r=rr,$fn=fnr*rr);
   }else if(r) {
    hh=sqrt(pow(r,2)-pow(d,2)/4);
    translate([0,0,hh]) sphere(r=r,$fn=fnr*r);
   }
  }
 
  % if(vitamins) mirrorleft() {
   translate([0,0,-epsilon]) mirror([0,0,1]) cylinder(d=gearbox_d,h=1,$fn=60);
   for(zr=[0:90:359]) rotate([0,0,zr]) translate([mount_d/2,0,0])
    cylinder(d=mount_screw_d,h=20,$fn=30);
   translate([0,0,-epsilon]) cylinder(d=protrusion_d,h=protrusion_h,$fn=30);
   translate([0,0,protrusion_h]) {
    difference() {
     cylinder(d=bore_d,h=bore_l,$fn=30);
     translate([-bore_d/2-1,bore_dd-bore_d/2,-1])
     cube([bore_d+2,bore_d/2,bore_l+2]);
    }
    translate([0,0,pulley_elevation]) {
     cylinder(d=pulley_d,h=pulley_h,$fn=30);
     translate([0,0,teeth_elevation]) {
      place_idler() {
       cylinder(d=idler_d,h=idler_h,center=true,$fn=30);
       cylinder(d=idler_screw_d,h=lever_thickness+2,center=true,$fn=30);
      }//place idler
      // filament path
      rotate([0,0,45]) {
       translate([pulley_d/2-idler_filament_offset,0,0]) rotate([90,0,0]) {
        cylinder(d=filament_d,h=gearbox_d,center=false,$fn=15);
       }//rotate translate
       translate([pulley_d/2+filament_offset,0,0]) rotate([-90,0,0]) {
        cylinder(d=filament_d,h=gearbox_d,center=false,$fn=15);
        translate([0,0,mount_d/sqrt(2)/2+mount_screw_d])
        pushfit(pf);
       }//rotate translate
@@ -243,102 +250,102 @@ module the_extruder(
         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+filament_offset,0,0])
     rotate([-90,0,0])
     translate([0,0,mount_d/sqrt(2)/2+mount_screw_d-gearbox_d/2/*TODO:*/]) {
      pfbl = pf_h(pf)+gearbox_d/2; //TODO:
      if(pf_smooth) {
       pfbd = pf_d(pf)+2*pf_shell;
       hull() {
        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)])
+    translate([0,0,mount_screw_l-mount_depth-(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,
+             h=mount_screw_l-mount_depth+1,
              $fn=fnd*(mount_screw_d+mount_screw_d_tolerance));
-    translate([0,0,mount_screw_l-mounthole_depth/2])
+    translate([0,0,mount_screw_l-mount_depth])
     cylinder(d=mount_screwhead_d,h=body_h+1,$fn=fnd*mount_screwhead_d);
    }//for
    // pushfit
    translate([0,0,filament_elevation])
    rotate([0,0,45]) translate([pulley_d/2+filament_offset,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,$fn=fnd*filament_guide_d);
     translate([0,-filament_guide_d/2/sqrt(2),0])
     rotate([0,0,45])
     cube(size=[filament_guide_d/2,filament_guide_d/2,gearbox_d],center=true);
    }//rotate translate rotate translate rotate translate
    // pulley
    cylinder(d=pulley_d+pulley_d_clearance,h=body_h+1,$fn=fnd*(pulley_d+pulley_d_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
    // XXX: this is somewhat ugly and potentially bugged,
    //      but I want to sleep.
    a0_ = atan(
     (mount_d/sqrt(2)/2+mount_screw_d+pf_h(pf)+gearbox_d/2)
     /
     (
      pulley_d/2+filament_offset-
      (pf_d(pf)+2*pf_shell)/2/cos(30)
     )
    );
    a0 = -135 + ( (a0_>0) ? a0_ : 180+a0_ );
    a1 = atan((longwing-lever_thickness/2)/(gearbox_d/2));
    translate([0,0,ls_z]) difference() {
     rotate([0,0,-180+a0])