make the blow target adjustable

blow a bit below layer printed to target the neighborhood instead of
the very nozzle

1 files changed, 5 insertions, 4 deletions

diff --git a/fanduct.scad b/fanduct.scad
index 7fc1ff4..f4bb705 100644
--- a/fanduct.scad
+++ b/fanduct.scad
@@ -1,196 +1,197 @@
 use <snapper.scad>;
         extrusion_width=.5; layer_height=.2;    // print parameters
 
         epsilon=.005;   // for finer cuts
 
         heater_w = 16;  // heatblock width
         heater_l = 20;  // heatblock length
         nozzle_offset=4.5;// nozzle offset from the edge of heatblock
 
         fanduct_elevation = 3;                                          // fanduct elevation above nozzle tip
+        fanduct_blowtarget = -2;                                        // what to blow at
         fanduct_h = 6;                                                  // inner height of the duct
         fanduct_w = 7;                                                  // inner width of the duct
         fanduct_shell=1.2;                                              // shell thickness
         fanduct_ir = sqrt(pow(heater_w/2,2)+pow(heater_l-nozzle_offset,2))+5;// inner radius
 
         jet_angle = 60;         // angular width of the jet
 
         inlet_w = 12.5;         // inlet width
         inlet_h = 17;   // inlet height
         inlet_l = 7;    // inlet length of protrusion (or depth of intrusion:))
         inlet_away = 15;// how far away inlet is
 
 hotend_clearance = 12;
 
         snapper_d = 8; snapper_overlap=0.2;// snip snap
 
 smooth_f = 120;
 
 type="3jets"; // "3jets" ; // circular|3jets
 
 
 module fanduct(type=type) {
 
          //     ***duct is all around!
  module duct(what) {
   if(what=="in") {
    sh = fanduct_w+2*fanduct_shell; sv = fanduct_h+2*fanduct_shell;
    smax = max(sh,sv);
    rotate_extrude($fn=smooth_f)
    translate([sh/2+fanduct_ir,sv/2])
    scale([sh/smax,sv/smax])
    circle(d=smax,$fn=4*smax);
   }else if(what=="out") {
    sh = fanduct_w; sv = fanduct_h;
    smax = max(sh,sv);
    rotate_extrude($fn=smooth_f)
    translate([sh/2+fanduct_shell+fanduct_ir,sv/2+fanduct_shell])
    scale([sh/smax,sv/smax])
    circle(d=smax,$fn=4*smax);
   }
  }
 
          //     ***bumps for easier position adjustments in line with hotend
  module marks(what) {
   if(what=="in") {
    for(y=[-1,1])
     hull() for(z=[0,-fanduct_shell-fanduct_h/2])
      translate([0,y*(fanduct_ir+fanduct_shell+fanduct_w/2),fanduct_shell*2+fanduct_h+z])
      rotate([90,0,0]) {
       cylinder(r=fanduct_shell,h=fanduct_w,center=true,$fn=30);
       for(z=[-1,1]) translate([0,0,z*fanduct_w/2])
        sphere(r=fanduct_shell,$fn=30);
      }
   }
  }
 
          //     ***output
  module output(what,type=type) {
   module guideline(xyxy) {
    module pin(xy) {
     translate([xy[0],xy[1],0])
     cylinder(d=2*extrusion_width,h=2*fanduct_shell+inlet_h,$fn=6);
    }
    xyxyxy=concat(xyxy,[[0,0]]);
    for(i=[0:1:len(xyxyxy)-2])
     hull() for(j=[i,i+1]) pin(xyxyxy[j]);
   }
 
   module circus(what) {
    if(what=="in") {
     difference() {
      rotate_extrude($fn=smooth_f)
       polygon([
-       [0,-fanduct_elevation],
+       [0,-fanduct_elevation+fanduct_blowtarget+epsilon],
        [fanduct_ir+fanduct_shell,fanduct_shell+fanduct_h/2],
        [fanduct_ir+fanduct_shell+fanduct_w/2,0],
-       [0,-fanduct_elevation-.1]]);
+       [0,-fanduct_elevation+fanduct_blowtarget-epsilon]]);
      translate([0,0,-1])
      cylinder(r=hotend_clearance,h=fanduct_h+2*fanduct_shell+2,$fn=smooth_f);
      mirror([0,0,1])
      translate([0,0,-epsilon])
      cylinder(r=fanduct_ir+fanduct_shell+1,h=fanduct_elevation+.1+2);
     }
    }else if(what=="out") {
     rotate_extrude($fn=smooth_f)
     polygon([
-     [0,-fanduct_elevation],
+     [0,-fanduct_elevation+fanduct_blowtarget+epsilon],
      [fanduct_ir+fanduct_shell+1,fanduct_h/2],
      [fanduct_ir+fanduct_w/2+fanduct_shell+1,fanduct_shell],
-     [0,-fanduct_elevation-.1]]);
+     [0,-fanduct_elevation+fanduct_blowtarget-epsilon]]);
    }else if(what=="airguides") {
     inr = fanduct_ir+fanduct_shell; our = inr+fanduct_w;
     union() {
      for(my=[0,1]) mirror([0,my,0]) {
       guideline([
        [-our,inlet_w/6],
        [-inr*sin(60),inr*cos(60)]
       ]);
       a0=30; as=15; a1=180;
       for(a=[a0+as:as:a1]) {
        f = as/(a1-a+as);
        rotate([0,0,a]) guideline([[-inr-fanduct_w*f,0]]);
       }
       guideline([
        [-our+fanduct_w*cos(30)*3/4,fanduct_w*sin(30)*3/4],
        [-inr*cos(10),inr*sin(10)]
       ]);
      }
     }/*union*/
    }/*airguides*/
   }
 
   module jets(what) {
    od = fanduct_h/2+fanduct_shell;
    md = fanduct_ir+fanduct_shell+fanduct_w/2;
    jww = 2*md*sin(jet_angle/2);
    render(convexity=8) difference() {
     for(a=[0:120:359]) rotate([0,0,a]) {
      if(what=="in") {
       hull() {
        render(convexity=4) intersection() {
         translate([md-fanduct_shell-fanduct_w/2,-jww/2,0])
         cube(size=[fanduct_shell+fanduct_w/2,jww,od]);
         duct(what=what);
        }
        translate([0,0,-fanduct_elevation]) sphere(r=.5);
       }
      }else if(what=="out") {
       hull() {
        render(convexity=4) intersection() {
         translate([md-fanduct_w/2-fanduct_shell,-jww/2+fanduct_shell,fanduct_shell])
         cube(size=[fanduct_w/2+fanduct_shell,jww-2*fanduct_shell,od-2*fanduct_shell]);
         duct(what=what);
        }
        translate([0,0,-fanduct_elevation]) sphere(r=.2);
       }
      }
     }
     if(what=="in") {
      translate([0,0,-fanduct_elevation-2+epsilon])
      cylinder(r=fanduct_ir+fanduct_shell*2+fanduct_w+1,h=fanduct_elevation+2);
      translate([0,0,-hotend_clearance])
      rotate([0,0,30])
      cylinder(r1=hotend_clearance*2,r2=0,h=hotend_clearance*2,$fn=6);
     }
    }
   }
 
   if(type=="circular") circus(what);
   else if(type=="3jets") jets(what);
  }
 
          //     ***air intake
  module intake(what) {
   module placeit() {
    translate([-fanduct_ir-2*fanduct_shell-fanduct_w-inlet_away,0,fanduct_shell])
    rotate([0,-90,0])
    children();
   }
   if(what=="in") {
    placeit() translate([0,-inlet_w/2,0]) {
     cube(size=[inlet_h,inlet_w,inlet_l+fanduct_shell]);
     // supports
     for(i=[-1,0,1])
      translate([-fanduct_shell,
       (i+1)*(inlet_w-extrusion_width)/2,
      -inlet_away-fanduct_w/2])
      cube(size=[fanduct_shell,
       extrusion_width,
       inlet_l+fanduct_shell+inlet_away+fanduct_w/2]);
    }
    hull() {
     placeit() translate([-fanduct_shell,-inlet_w/2-fanduct_shell,0])
     cube(size=[inlet_h+2*fanduct_shell,inlet_w+2*fanduct_shell,fanduct_shell]);
     translate([-fanduct_ir-fanduct_shell-fanduct_w/2,0,0])
     translate([0,-inlet_w/2-fanduct_shell/2,0])
     cube(size=[1,inlet_w+fanduct_shell,fanduct_shell*2+fanduct_h]);
    }
   }else if(what=="out") {
    placeit() translate([fanduct_shell,-inlet_w/2+fanduct_shell,0])
    cube(size=[inlet_h-2*fanduct_shell,inlet_w-2*fanduct_shell,inlet_l+fanduct_shell+1]);
    hull() {
     placeit() translate([fanduct_shell,-inlet_w/2+fanduct_shell,0])
     cube(size=[inlet_h-2*fanduct_shell,inlet_w-2*fanduct_shell,fanduct_shell]);
     translate([-fanduct_ir-fanduct_shell-fanduct_w/2,0,fanduct_shell])
     translate([0,-inlet_w/2+fanduct_shell,0])