diff --git a/js/kiri-print.js b/js/kiri-print.js
index 0268cbc3..4449bda7 100644
--- a/js/kiri-print.js
+++ b/js/kiri-print.js
@@ -305,7 +305,7 @@ var gs_kiri_print = exports;
      */
     function addOutput(array, point, emit, speed, tool) {
         // drop duplicates (usually intruced by bisections)
-        if (lastPoint && point.x == lastPoint.x && point.y == lastPoint.y && lastEmit == emit) {
+        if (lastPoint && point.x == lastPoint.x && point.y == lastPoint.y && point.z == lastPoint.z && lastEmit == emit) {
             return;
         }
         lastPoint = point;