diff --git a/HeatSink.scad b/HeatSink.scad
index 9f8bd73dfee0af6b814f8172e631421a7e85d3d5..f05268317242dff41052094f8d140936bfd752a4 100644
--- a/HeatSink.scad
+++ b/HeatSink.scad
@@ -1,8 +1,4 @@
 
-$fs = 0.2;
-$fa = $fs;
-
-
 use <WebWeaver/scad/Util.scad>;
 use <WebWeaver/scad/Piping.scad>;
 
@@ -286,19 +282,37 @@ module splitFunnel() {
 
 
 
+// TODO: choose a better name!
+// `overallSystem` describes it… but it sound bad :(
+module overallSystem() {
 
+  if ($preview) {
+    
+    $fs = 0.5;
+    $fa = 10;
 
-module preview() {
+    // display heat sink only in render mode
+    rotate([180, 0, 0]) symmetricHeatsink();
+    
+    
+    // translate([0, 0, 0]) curvyFunnel();  
+    translate([0, 0, 0]) splitFunnel();
 
-  // translate([0, 0, 0]) curvyFunnel();
-  
-  translate([0, 0, 0]) splitFunnel();
+    // color([0, 0, 1.0, 1.0]) translate([0, 0, 1]) linear_extrude(1) funnelFins();
+  } else {
 
-  // color([0, 0, 1.0, 1.0]) translate([0, 0, 1]) linear_extrude(1) funnelFins();
-  
-  rotate([180, 0, 0]) symmetricHeatsink();
+    $fs = 0.2;
+    $fa = 1.0;
+    
+    // TODO: 3D-Print positioning!
+
+    // translate([0, 0, 0]) curvyFunnel();  
+    translate([0, 0, 0]) splitFunnel();
+
+    // color([0, 0, 1.0, 1.0]) translate([0, 0, 1]) linear_extrude(1) funnelFins();
+  }
 }
 
 
-preview();
+overallSystem();