diff --git a/boxes/__init__.py b/boxes/__init__.py
index 6b3ba93..46a716c 100755
--- a/boxes/__init__.py
+++ b/boxes/__init__.py
@@ -1689,6 +1689,42 @@ class Boxes:
 
         self.move(overallwidth, overallheight, move)
 
+    def surroundingWallPiece(self, cbnr, x, y, r, pieces=1):
+        """
+        Return the geometry of a pices of surroundingWall with the given
+        callback number.
+        :param cbnr: number of the callback corresponding to
+                     this part of the wall
+        :param x: width of matching roundedPlate
+        :param y: height of matching roundedPlate
+        :param r: corner radius of matching roundedPlate
+        :param pieces: (Default value = 1) number of separate pieces
+        :return: (left, length, right) left and right are Booleans that are
+        True if the start or end of the wall is on that side.
+        """
+        if pieces<=2 and (y - 2 * r) < 1E-3:
+            # remove zero length y sides
+            sides = (x/2-r, x - 2*r, x - 2*r)
+            if pieces > 0: # hack to get the right splits
+                pieces += 1
+        else:
+            sides = (x/2-r, y - 2*r, x - 2*r, y - 2*r, x - 2*r)
+
+        wallcount = 0
+        for nr, l in enumerate(sides):
+            if self._splitWall(pieces, nr) and nr > 0:
+                if wallcount == cbnr:
+                    return (False, l/2, True)
+                wallcount += 1
+                if wallcount == cbnr:
+                    return (True, l/2, False)
+                wallcount += 1
+            else:
+                if wallcount == cbnr:
+                    return (False, l, False)
+                wallcount += 1
+        return (False, 0.0, False)
+
     def surroundingWall(self, x, y, r, h,
                         bottom='e', top='e',
                         left="D", right="d",
diff --git a/boxes/generators/roundedbox.py b/boxes/generators/roundedbox.py
index 374ca1f..92ff96c 100644
--- a/boxes/generators/roundedbox.py
+++ b/boxes/generators/roundedbox.py
@@ -36,7 +36,7 @@ With lid:
         boxes.Boxes.__init__(self)
         self.addSettingsArgs(boxes.edges.FingerJointSettings)
         self.addSettingsArgs(boxes.edges.FlexSettings)            
-        self.buildArgParser("x", "y", "h", "outside")
+        self.buildArgParser("x", "y", "outside", sh="100.0")
         self.argparser.add_argument(
             "--radius", action="store", type=float, default=15,
             help="Radius of the corners in mm")
@@ -77,19 +77,28 @@ With lid:
             self.edge(l);
             self.corner(90, r)
 
+    def cb(self, nr):
+        h = 0.5 * self.thickness
+
+        left, l, right = self.surroundingWallPiece(nr, self.x, self.y, self.radius, self.wallpieces)
+        for dh in self.sh[:-1]:
+            h += dh
+            self.fingerHolesAt(0, h, l, 0)
+
     def render(self):
 
-        x, y, h, r = self.x, self.y, self.h, self.radius
+        x, y, sh, r = self.x, self.y, self.sh, self.radius
 
         if self.outside:
             self.x = x = self.adjustSize(x)
             self.y = y = self.adjustSize(y)
-            self.h = h = self.adjustSize(h)
+            self.sh = sh = self.adjustSize(sh)
 
         r = self.radius = min(r, y / 2.0)
 
         t = self.thickness
 
+        h = sum(sh) + t * (len(sh) - 1)
         es = self.edge_style
 
         corner_holes = True
@@ -107,6 +116,9 @@ With lid:
         with self.saved_context():
             self.roundedPlate(x, y, r, es, wallpieces=self.wallpieces,
                               extend_corners=ec, move="right")
+            for dh in self.sh[:-1]:
+                self.roundedPlate(x, y, r, "f", wallpieces=self.wallpieces,
+                                  extend_corners=False, move="right")
             self.roundedPlate(x, y, r, es, wallpieces=self.wallpieces,
                               extend_corners=ec, move="right",
                               callback=[self.hole] if self.top != "closed" else None)
@@ -120,6 +132,7 @@ With lid:
 
         self.roundedPlate(x, y, r, es, wallpieces=self.wallpieces, move="up only")
 
-        self.surroundingWall(x, y, r, h, pe, pe, pieces=self.wallpieces)
+        self.surroundingWall(x, y, r, h, pe, pe, pieces=self.wallpieces,
+                             callback=self.cb)