diff --git a/nhf/touhou/houjuu_nue/wing.py b/nhf/touhou/houjuu_nue/wing.py
index d05eaf5..46fd676 100644
--- a/nhf/touhou/houjuu_nue/wing.py
+++ b/nhf/touhou/houjuu_nue/wing.py
@@ -238,9 +238,13 @@ class WingRoot:
     """
 
     panel_thickness: float = 25.4 / 16
+    spacer_thickness: float = 25.4 / 8
     height: float = 100.0
-    shoulder_width: float = 20.0
-    root_width: float = 60.0
+    shoulder_width: float = 30.0
+    root_width: float = 80.0
+
+    tip_x: float = -200.0
+    tip_y: float = 160.0
 
     def outer_spline(self) -> list[Tuple[float, float]]:
         """
@@ -248,34 +252,81 @@ class WingRoot:
         """
 
     def profile(self) -> Cq.Sketch:
-        tip_x, tip_y = -100.0, 70.0
         sketch = (
             Cq.Sketch()
             .segment((-self.root_width, 0), (0, 0))
             .spline([
                 (0, 0),
-                (-30.0, 50.0),
-                (tip_x, tip_y)
+                (-30.0, 80.0),
+                (self.tip_x, self.tip_y)
             ])
             .segment(
-                (tip_x, tip_y),
-                (tip_x, tip_y - self.shoulder_width)
+                (self.tip_x, self.tip_y),
+                (self.tip_x, self.tip_y - self.shoulder_width)
             )
             .segment(
-                (tip_x, tip_y - self.shoulder_width),
+                (self.tip_x, self.tip_y - self.shoulder_width),
                 (-self.root_width, 0)
             )
             .assemble()
         )
         return sketch
 
-    def xy_surface(self) -> Cq.Workplane:
+    def spacer(self) -> Cq.Workplane:
+        """
+        Creates a rectangular spacer. This could be cut from acrylic.
 
-        return (
-            Cq.Workplane()
-            .placeSketch(self.profile())
-            .extrude(self.panel_thickness)
+        There are two holes on the top of the spacer. With the holes
+        """
+        length = self.height
+        width = 10.0
+        h = self.spacer_thickness
+        result = (
+            Cq.Workplane('XY')
+            .sketch()
+            .rect(length, width)
+            .finalize()
+            .extrude(h)
         )
+        # Tag the mating surfaces to be glued
+        result.faces("<X").workplane().tagPlane("left")
+        result.faces(">X").workplane().tagPlane("right")
+
+        # Tag the directrix
+        result.faces(">Z").tag("dir")
+        return result
+
+    def surface(self, top: bool = False) -> Cq.Workplane:
+        tags = [
+            ("shoulder", (self.tip_x, self.tip_y + 30), 0),
+            ("base", (-self.root_width,  0), 90),
+        ]
+        return nhf.utils.extrude_with_markers(
+            self.profile(),
+            self.panel_thickness,
+            tags,
+            reverse=not top,
+        )
+
+    def assembly(self) -> Cq.Assembly:
+        result = (
+            Cq.Assembly()
+            .add(self.surface(top=True), name="bot")
+            .add(self.surface(top=False), name="top")
+            .constrain("bot@faces@>Z", "top@faces@<Z", "Point",
+                       param=self.height)
+        )
+        for t in ["shoulder", "base"]:
+            name = f"{t}_spacer"
+            (
+                result
+                .add(self.spacer(), name=name)
+                .constrain(f"{name}?left", f"bot?{t}", "Plane")
+                .constrain(f"{name}?right", f"top?{t}", "Plane")
+                .constrain(f"{name}?dir", f"top?{t}_dir", "Axis")
+            )
+        return result.solve()
+
 
 @dataclass
 class WingProfile:
diff --git a/nhf/utils.py b/nhf/utils.py
index b1b92d8..9705afa 100644
--- a/nhf/utils.py
+++ b/nhf/utils.py
@@ -6,9 +6,34 @@ Adds the functions to `Cq.Workplane`:
 2. `tagPlane`
 """
 import math
+import functools
 import cadquery as Cq
 from nhf import Role
-from typing import Union, Tuple
+from typing import Union, Tuple, cast
+
+# Bug fixes
+def _subloc(self, name: str) -> Tuple[Cq.Location, str]:
+    """
+       Calculate relative location of an object in a subassembly.
+
+       Returns the relative positions as well as the name of the top assembly.
+       """
+
+    rv = Cq.Location()
+    obj = self.objects[name]
+    name_out = name
+
+    if obj not in self.children and obj is not self:
+        locs = []
+        while not obj.parent is self:
+            locs.append(obj.loc)
+            obj = cast(Cq.Assembly, obj.parent)
+            name_out = obj.name
+
+        rv = functools.reduce(lambda l1, l2: l2 * l1, locs)
+
+    return (rv, name_out)
+Cq.Assembly._subloc = _subloc
 
 
 def tagPoint(self, tag: str):