diff --git a/src/midpt_smooth.scad b/src/midpt_smooth.scad
index ac816c12..ffefd922 100644
--- a/src/midpt_smooth.scad
+++ b/src/midpt_smooth.scad
@@ -8,14 +8,17 @@
 *
 **/
 
-function _midpt_smooth_sub(points, iend, i, closed = false) = 
-    i == iend ? (
-        closed ? [(points[i] + points[0]) / 2]
-        : []
-    ) : concat([(points[i] + points[i + 1]) / 2], _midpt_smooth_sub(points, iend, i + 1, closed)); 
+function _midpt_smooth_sub(points, iend, closed = false) = 
+    concat(
+        [
+            for(i = 0; i < iend; i = i + 1) 
+                (points[i] + points[i + 1]) / 2
+        ],
+        closed ? [(points[iend] + points[0]) / 2] : []
+    );
 
 function midpt_smooth(points, n, closed = false) =
     let(
-        smoothed = _midpt_smooth_sub(points, len(points) - 1, 0, closed)
+        smoothed = _midpt_smooth_sub(points, len(points) - 1, closed)
     )
     n == 1 ? smoothed : midpt_smooth(smoothed, n - 1, closed);
\ No newline at end of file