diff --git a/scripts/addons/cam/curvecamcreate.py b/scripts/addons/cam/curvecamcreate.py
index f238f27f..3759e83e 100644
--- a/scripts/addons/cam/curvecamcreate.py
+++ b/scripts/addons/cam/curvecamcreate.py
@@ -182,6 +182,7 @@ class CamCurveMortise(bpy.types.Operator):
     top_bottom: bpy.props.BoolProperty(name="Side Top & bottom fingers", default=True)
     opencurve: bpy.props.BoolProperty(name="OpenCurve", default=False)
     interlocking_groove: bpy.props.BoolProperty(name="interlocking_groove", default=False)
+    twist: bpy.props.BoolProperty(name="twist_interlock", default=False)
     finger_amount: bpy.props.IntProperty(name="Finger Amount", default=2, min=1, max=100)
     tangent_angle: bpy.props.FloatProperty(name="Tangent deviation", default=0.0, min=0.000, max=2, subtype="ANGLE",
                                       unit="ROTATION")
@@ -251,7 +252,10 @@ class CamCurveMortise(bpy.types.Operator):
                                                  self.flex_pocket)
 
                 elif self.interlocking_groove:
-                    joinery.distributed_interlock(c, length, self.finger_size, self.plate_thickness, self.finger_tolerance, self.finger_amount, fixed_angle=self.fixed_angle, tangent=self.tangent_angle,closed=not self.opencurve)
+                    if self.twist:
+                        joinery.distributed_interlock(c, length, self.finger_size, self.plate_thickness, self.finger_tolerance, self.finger_amount, fixed_angle=self.fixed_angle, tangent=self.tangent_angle,closed=not self.opencurve, type='twist')
+                    else:
+                        joinery.distributed_interlock(c, length, self.finger_size, self.plate_thickness, self.finger_tolerance, self.finger_amount, fixed_angle=self.fixed_angle, tangent=self.tangent_angle,closed=not self.opencurve)
         return {'FINISHED'}
 
 
diff --git a/scripts/addons/cam/joinery.py b/scripts/addons/cam/joinery.py
index a787e114..33a33c89 100644
--- a/scripts/addons/cam/joinery.py
+++ b/scripts/addons/cam/joinery.py
@@ -62,7 +62,30 @@ def interlock_groove(length, thickness, finger_play, cx=0, cy=0, rotation=0):
     bpy.ops.object.transform_apply(location=True, rotation=False, scale=False)
     bpy.context.active_object.rotation_euler.z = rotation
     bpy.ops.transform.translate(value=(cx, cy, 0.0))
-#    bpy.context.active_object.name = "_groove"
+    bpy.context.active_object.name = "_groove"
+
+
+def interlock_twist(length, thickness, finger_play, cx=0, cy=0, rotation=0, percentage=0.5,):
+    mortise(length, thickness, finger_play, 0, 0, 0)
+    bpy.context.active_object.name = "_tmp"
+    mortise(length*percentage, thickness, finger_play, 0, 0, math.pi/2)
+    bpy.context.active_object.name = "_tmp"
+    h = math.hypot(thickness, length*percentage)
+    oangle = math.degrees(math.asin(length*percentage/h))
+    bpy.ops.curve.simple(align='WORLD', location=(0, 0, 0), rotation=(0, 0, 0), Simple_Type='Sector',
+                         Simple_startangle=90+oangle, Simple_endangle=180-oangle, Simple_radius=h/2, use_cyclic_u=True, edit_mode=False)
+    bpy.context.active_object.name = "_tmp"
+
+    bpy.ops.curve.simple(align='WORLD', location=(0, 0, 0), rotation=(0, 0, 0), Simple_Type='Sector',
+                         Simple_startangle=270+oangle, Simple_endangle=360-oangle, Simple_radius=h/2, use_cyclic_u=True, edit_mode=False)
+    bpy.context.active_object.name = "_tmp"
+
+    simple.selectMultiple('_tmp')
+    bpy.ops.object.curve_boolean(boolean_type='UNION')
+    bpy.context.active_object.rotation_euler.z = rotation
+    bpy.ops.transform.translate(value=(cx, cy, 0.0))
+    bpy.context.active_object.name = "_groove"
+    simple.removeMultiple('_tmp')
 
 
 def horizontal_finger(length, thickness, finger_play, amount, center=True):
@@ -413,7 +436,7 @@ def variable_finger(loop, loop_length, min_finger, finger_size, finger_thick, fi
     return hpos
 
 
-def distributed_interlock(loop, loop_length, finger_depth, finger_thick, finger_tolerance, finger_amount, tangent=0, fixed_angle=0, start=0.01, end=0.01, closed=True):
+def distributed_interlock(loop, loop_length, finger_depth, finger_thick, finger_tolerance, finger_amount, tangent=0, fixed_angle=0, start=0.01, end=0.01, closed=True, type='groove'):
     #   distributes interlocking joints of a fixed amount
     #   dynamically changes the finger tolerance with the angle differences
     #   loop = takes in a shapely shape
@@ -454,14 +477,15 @@ def distributed_interlock(loop, loop_length, finger_depth, finger_thick, finger_
                 groove_point = loop.interpolate(distance)
 
                 print(j, "groove_angle", round(180*(groove_angle)/math.pi),"distance", round(distance * 1000),"mm")
-                interlock_groove(finger_depth, finger_thick, finger_tolerance, groove_point.x, groove_point.y,
+                if type == "groove":
+                    interlock_groove(finger_depth, finger_thick, finger_tolerance, groove_point.x, groove_point.y,groove_angle)
+                elif type == "twist":
+                    interlock_twist(finger_depth, finger_thick, finger_tolerance, groove_point.x, groove_point.y,
                         groove_angle)
 
-
                 j += 1
                 distance = j * spacing + start
         oldp = p
 
-    simple.joinMultiple("_mort")
-    bpy.context.active_object.name = "mortise"
-
+    simple.joinMultiple("_groove")
+    bpy.context.active_object.name = "groove"