3 files changed, 143 insertions, 0 deletions

diff --git a/multimixer.scad b/multimixer.scad
new file mode 100644
index 0000000..88fd6bf
--- a/dev/null
+++ b/multimixer.scad
@@ -0,0 +1,79 @@
+layer_height=.2; extrusion_width=.5;
+epsilon=.01;
+
+use <pushfittery.scad>;
+include <pushfit_data.scad>;
+
+module multimixer(
+ filament_d = 1.75,
+ liner_od = 4, liner_id = 2,
+ angle = 15,    // to the vertical (output) axis
+ inputs = 4,
+ minshell = 2*extrusion_width,
+ shell = 5*extrusion_width,
+ pf = pushfit_embeddest,
+ debug = true
+) {
+ fnd = 4*PI; fnr = 2*fnd;
+ 
+ pushfit_d = pf_d(pf);
+ pushfit_h = pf_h(pf);
+ 
+ angular_step = 360/inputs;
+ inputogon_angle = 180*(inputs-2)/inputs;
+ 
+ sinsin = sin(angle)*sin(angular_step/2);
+ function l_to(d) = d*cos(asin(sinsin))/sinsin;
+ l_output = liner_od;
+ l_input = l_to(pushfit_d/2+minshell);
+ l_fork = l_to(liner_id/2);
+ l_narrow = l_to(liner_od/2+minshell);
+ 
+ module forinputs() {
+  for(zr=[0:angular_step:359]) rotate([0,0,zr]) rotate([0,angle,0]) children();
+ }//forinputs module
+ module foroutput() {
+  rotate([180,0,0]) children();
+ }
+ 
+ //translate([pf_d(pf)/2+shell,0,0])
+ //translate([0,0,l_output+pushfit_h])
+ difference() {
+  hull() {
+   forinputs()
+    translate([0,0,l_input+pushfit_h]) mirror([0,0,1])
+    cylinder(d=pushfit_d+shell*2,h=epsilon,$fn=pushfit_d*fnd);
+   foroutput()
+    translate([0,0,l_output+pushfit_h]) {
+     cylinder(d=pushfit_d+shell*2,h=epsilon,$fn=pushfit_d*fnd);
+    }
+  }
+  forinputs() {
+   translate([0,0,l_input]) pushfit(pf);
+   translate([0,0,l_narrow]) {
+    cylinder(d=liner_od,h=l_input+1-l_narrow,$fn=liner_od*fnd);
+    mirror([0,0,1]) translate([0,0,-epsilon])
+    cylinder(d1=(liner_id+liner_od)/2,d2=liner_id,h=liner_id,$fn=liner_od*fnd);
+   }
+   cylinder(d=liner_id,h=l_input+epsilon,$fn=liner_id*fnd);
+  }
+  foroutput() {
+   translate([0,0,l_output]) pushfit(pf);
+   cylinder(d=liner_od,h=l_input+1,$fn=liner_od*fnd);
+  }
+  hull() {
+   forinputs()
+    translate([0,0,l_fork]) cylinder(d=liner_id,h=epsilon,$fn=liner_id*fnd);
+   foroutput()
+    cylinder(d=liner_id,h=epsilon,$fn=liner_id*fnd);
+  }
+  if(debug) {
+   translate([0,0,-20/*TODO:*/])
+   rotate_extrude(angle=angular_step)
+   square([50,100]/*TODO:*/);
+  }
+ }
+
+}
+
+multimixer(debug=true);
diff --git a/pushfit_data.scad b/pushfit_data.scad
new file mode 100644
index 0000000..c0ce3d0
--- a/dev/null
+++ b/pushfit_data.scad
@@ -0,0 +1,21 @@
+pushfit_embeddest = [ ["type", "embeddest"],
+ ["d",  8],             // outer diameter of legspace
+ ["id", 6],             // inner diameter, the narrow passage
+ ["h",  7],             // total height
+ ["h_legspace", 3.2],   // the height of legspace
+ ["ch", 1]             // inlet chamfer
+];
+pushfit_embedded = [ ["type", "embedded"],
+ ["d", 12],             // outer diameter
+ ["h", 7 ],             // total height
+ ["h_ring", 4.7],       // height of embedded pushfit ring
+ ["d_insert", 8],       // diameter of pushfit insert legs hole
+];
+pushfit_threaded = [ ["type", "threaded"],
+ ["h", 10],             // total height
+ ["d", 25.4*3/8 ],      // the diameter to return
+ ["d_tolerance", 0.5],  // the diameter tolerance
+ ["tpi", 28]           // threads per inch
+];
+
+
diff --git a/pushfittery.scad b/pushfittery.scad
new file mode 100644
index 0000000..adebec2
--- a/dev/null
+++ b/pushfittery.scad
@@ -0,0 +1,43 @@
+draft = true;
+
+use <threads.scad>;
+
+function pf_(d,k) = d[search([k],d)[0]][1];
+function pf_d(pf) = pf_(pf,"d");
+function pf_h(pf) = pf_(pf,"h");
+module pushfit(pf,draft=draft) {
+ fnd = 2*PI; epsilon=.01;
+ type = pf_(pf,"type");
+ h = pf_h(pf);
+ if(type=="threaded") {
+  minch = 25.4;
+  d = (pf_d(pf) + pf_(pf,"d_tolerance"))/minch;
+  tpi = pf_(pf,"tpi");
+  if(draft) cylinder(d=d*minch,h=h+epsilon);
+  else english_thread(diameter=d,threads_per_inch=tpi,length=h/minch+epsilon,internal=true);
+  slitl = d*minch+layer_height;
+  slitw = 0.8*d*minch/2;
+  echo(slitw,slitl);
+  translate([-slitw/2,-slitl/2,0]) cube([slitw,slitl,h+epsilon]);
+ }else if(type=="embedded") {
+  d = pf_d(pf);
+  h_ring = pf_(pf,"h_ring");
+  d_insert = pf_(pf,"d_insert");
+  $fn = d*fnd;
+  translate([0,0,h-h_ring]) cylinder(d=d,h=h_ring+epsilon);
+  cylinder(d=d_insert,h=h);
+ }else if(type=="embeddest") {
+  d = pf_d(pf);
+  id = pf_(pf,"id");
+  h_legspace = pf_(pf,"h_legspace");
+  ch = pf_(pf,"ch");
+  $fn = d*fnd;
+  cylinder(d=id,h=h+1);
+  cylinder(d=d,h=h_legspace);
+  dd = (d-id)/2;
+  translate([0,0,h_legspace-epsilon])
+  cylinder(d1=d,d2=id-2*epsilon,h=dd+epsilon);
+  translate([0,0,h-ch-epsilon])
+  cylinder(d1=id-2*epsilon,d2=id+2*ch+2,h=ch+epsilon+1);
+ }
+}//pushfit module