diff --git a/bindings/c/include/manifold/manifoldc.h b/bindings/c/include/manifold/manifoldc.h
index 7dd725c34..f8ab09ee4 100644
--- a/bindings/c/include/manifold/manifoldc.h
+++ b/bindings/c/include/manifold/manifoldc.h
@@ -167,6 +167,7 @@ ManifoldManifold *manifold_revolve(void *mem, ManifoldPolygons *cs,
                                    int circular_segments);
 ManifoldManifold *manifold_compose(void *mem, ManifoldManifoldVec *ms);
 ManifoldManifoldVec *manifold_decompose(void *mem, ManifoldManifold *m);
+
 ManifoldManifold *manifold_as_original(void *mem, ManifoldManifold *m);
 
 // Manifold Info
diff --git a/bindings/python/manifold3d.cpp b/bindings/python/manifold3d.cpp
index e9000ff46..921bb899f 100644
--- a/bindings/python/manifold3d.cpp
+++ b/bindings/python/manifold3d.cpp
@@ -233,9 +233,8 @@ NB_MODULE(manifold3d, m) {
 
   nb::class_<Manifold>(m, "Manifold")
       .def(nb::init<>(), manifold__manifold)
-      .def(nb::init<const MeshGL &, const std::vector<float> &>(),
-           nb::arg("mesh"), nb::arg("property_tolerance") = nb::list(),
-           manifold__manifold__mesh_gl__property_tolerance)
+      .def(nb::init<const MeshGL &>(), nb::arg("mesh"),
+           manifold__manifold__mesh_gl)
       .def(nb::self + nb::self, manifold__operator_plus__q)
       .def(nb::self - nb::self, manifold__operator_minus__q)
       .def(nb::self ^ nb::self, manifold__operator_xor__q)
@@ -348,7 +347,9 @@ NB_MODULE(manifold3d, m) {
           "Get the surface area of the manifold\n This is clamped to zero for "
           "a given face if they are within the Precision().")
       .def("original_id", &Manifold::OriginalID, manifold__original_id)
-      .def("as_original", &Manifold::AsOriginal, manifold__as_original)
+      .def("as_original", &Manifold::AsOriginal,
+           nb::arg("property_tolerance") = nb::list(),
+           manifold__as_original__property_tolerance)
       .def("is_empty", &Manifold::IsEmpty, manifold__is_empty)
       .def("decompose", &Manifold::Decompose, manifold__decompose)
       .def("split", &Manifold::Split, nb::arg("cutter"),
diff --git a/bindings/wasm/bindings.cpp b/bindings/wasm/bindings.cpp
index 07e7323f6..f27a20eba 100644
--- a/bindings/wasm/bindings.cpp
+++ b/bindings/wasm/bindings.cpp
@@ -167,7 +167,7 @@ EMSCRIPTEN_BINDINGS(whatever) {
       .function("calculateCurvature", &Manifold::CalculateCurvature)
       .function("_CalculateNormals", &Manifold::CalculateNormals)
       .function("originalID", &Manifold::OriginalID)
-      .function("asOriginal", &Manifold::AsOriginal);
+      .function("_AsOriginal", &Manifold::AsOriginal);
 
   // Manifold Static Methods
   function("_Cube", &Manifold::Cube);
diff --git a/bindings/wasm/bindings.js b/bindings/wasm/bindings.js
index b413859fc..bdd5c6ee2 100644
--- a/bindings/wasm/bindings.js
+++ b/bindings/wasm/bindings.js
@@ -228,6 +228,14 @@ Module.setup = function() {
     return this._CalculateNormals(normalIdx, minSharpAngle);
   };
 
+  Module.Manifold.prototype.asOriginal = function(propertyTolerance = []) {
+    const tol = new Module.Vector_f64();
+    toVec(tol, propertyTolerance);
+    const result = this._AsOriginal(tol);
+    tol.delete();
+    return result
+  };
+
   Module.Manifold.prototype.setProperties = function(numProp, func) {
     const oldNumProp = this.numProp();
     const wasmFuncPtr = addFunction(function(newPtr, vec3Ptr, oldPtr) {
diff --git a/src/manifold/include/manifold/manifold.h b/src/manifold/include/manifold/manifold.h
index 0ed82cedb..15d78bb0c 100644
--- a/src/manifold/include/manifold/manifold.h
+++ b/src/manifold/include/manifold/manifold.h
@@ -175,9 +175,9 @@ class Manifold {
   Manifold(Manifold&&) noexcept;
   Manifold& operator=(Manifold&&) noexcept;
 
-  Manifold(const MeshGL&, const std::vector<float>& propertyTolerance = {});
+  Manifold(const MeshGL&);
   Manifold(const Mesh&);
-  Manifold(const MeshGL64&, const std::vector<double>& propertyTolerance = {});
+  Manifold(const MeshGL64&);
 
   static Manifold Smooth(const MeshGL&,
                          const std::vector<Smoothness>& sharpenedEdges = {});
@@ -249,7 +249,7 @@ class Manifold {
    */
   ///@{
   int OriginalID() const;
-  Manifold AsOriginal() const;
+  Manifold AsOriginal(const std::vector<double>& propertyTolerance = {}) const;
   static uint32_t ReserveIDs(uint32_t);
   ///@}
 
diff --git a/src/manifold/src/constructors.cpp b/src/manifold/src/constructors.cpp
index 397c6701c..b4a8340c5 100644
--- a/src/manifold/src/constructors.cpp
+++ b/src/manifold/src/constructors.cpp
@@ -52,10 +52,7 @@ Manifold Manifold::Smooth(const MeshGL& meshGL,
                "when supplying tangents, the normal constructor should be used "
                "rather than Smooth().");
 
-  // Don't allow any triangle merging.
-  std::vector<float> propertyTolerance(meshGL.numProp - 3, -1);
-  std::shared_ptr<Impl> impl =
-      std::make_shared<Impl>(meshGL, propertyTolerance);
+  std::shared_ptr<Impl> impl = std::make_shared<Impl>(meshGL);
   impl->CreateTangents(impl->UpdateSharpenedEdges(sharpenedEdges));
   return Manifold(impl);
 }
@@ -94,10 +91,7 @@ Manifold Manifold::Smooth(const MeshGL64& meshGL64,
                "when supplying tangents, the normal constructor should be used "
                "rather than Smooth().");
 
-  // Don't allow any triangle merging.
-  std::vector<double> propertyTolerance(meshGL64.numProp - 3, -1);
-  std::shared_ptr<Impl> impl =
-      std::make_shared<Impl>(meshGL64, propertyTolerance);
+  std::shared_ptr<Impl> impl = std::make_shared<Impl>(meshGL64);
   impl->CreateTangents(impl->UpdateSharpenedEdges(sharpenedEdges));
   return Manifold(impl);
 }
@@ -278,7 +272,6 @@ Manifold Manifold::Extrude(const Polygons& crossSection, double height,
 
   pImpl_->CreateHalfedges(triVertsDH);
   pImpl_->Finish();
-  pImpl_->meshRelation_.originalID = ReserveIDs(1);
   pImpl_->InitializeOriginal();
   pImpl_->CreateFaces();
   return Manifold(pImpl_);
@@ -423,7 +416,6 @@ Manifold Manifold::Revolve(const Polygons& crossSection, int circularSegments,
 
   pImpl_->CreateHalfedges(triVertsDH);
   pImpl_->Finish();
-  pImpl_->meshRelation_.originalID = ReserveIDs(1);
   pImpl_->InitializeOriginal();
   pImpl_->CreateFaces();
   return Manifold(pImpl_);
diff --git a/src/manifold/src/impl.cpp b/src/manifold/src/impl.cpp
index 590e51860..390554aec 100644
--- a/src/manifold/src/impl.cpp
+++ b/src/manifold/src/impl.cpp
@@ -294,9 +294,6 @@ Manifold::Impl::Impl(const Mesh& mesh, const MeshRelationD& relation,
   CalculateNormals();
 
   InitializeOriginal();
-  if (!hasFaceIDs) {
-    CreateFaces(propertyTolerance);
-  }
 
   SimplifyTopology();
   Finish();
@@ -350,7 +347,6 @@ Manifold::Impl::Impl(Shape shape, const mat4x3 m) {
   for (auto& v : vertPos_) v = m * vec4(v, 1.0);
   CreateHalfedges(triVerts);
   Finish();
-  meshRelation_.originalID = ReserveIDs(1);
   InitializeOriginal();
   CreateFaces();
 }
@@ -392,9 +388,8 @@ void Manifold::Impl::RemoveUnreferencedVerts() {
 }
 
 void Manifold::Impl::InitializeOriginal() {
-  const int meshID = meshRelation_.originalID;
-  // Don't initialize if it's not an original
-  if (meshID < 0) return;
+  const int meshID = ReserveIDs(1);
+  meshRelation_.originalID = meshID;
   auto& triRef = meshRelation_.triRef;
   triRef.resize(NumTri());
   for_each_n(autoPolicy(NumTri(), 1e5), countAt(0), NumTri(),
@@ -407,9 +402,11 @@ void Manifold::Impl::InitializeOriginal() {
 
 void Manifold::Impl::CreateFaces(const std::vector<double>& propertyTolerance) {
   ZoneScoped;
+  constexpr double kDefaultPropTolerance = 1e-5;
   Vec<double> propertyToleranceD =
-      propertyTolerance.empty() ? Vec<double>(meshRelation_.numProp, kTolerance)
-                                : propertyTolerance;
+      propertyTolerance.empty()
+          ? Vec<double>(meshRelation_.numProp, kDefaultPropTolerance)
+          : propertyTolerance;
 
   Vec<std::pair<int, int>> face2face(halfedge_.size(), {-1, -1});
   Vec<std::pair<int, int>> vert2vert(halfedge_.size(), {-1, -1});
@@ -569,7 +566,7 @@ void Manifold::Impl::WarpBatch(std::function<void(VecView<vec3>)> warpFunc) {
   faceNormal_.resize(0);  // force recalculation of triNormal
   CalculateNormals();
   SetPrecision();
-  CreateFaces();
+  InitializeOriginal();
   Finish();
 }
 
diff --git a/src/manifold/src/impl.h b/src/manifold/src/impl.h
index 8ea88b36f..7c82b1fa7 100644
--- a/src/manifold/src/impl.h
+++ b/src/manifold/src/impl.h
@@ -66,8 +66,7 @@ struct Manifold::Impl {
   Impl(Shape, const mat4x3 = mat4x3(1));
 
   template <typename Precision>
-  Impl(const MeshGLP<Precision>& meshGL,
-       std::vector<Precision> propertyTolerance) {
+  Impl(const MeshGLP<Precision>& meshGL) {
     const uint32_t numVert = meshGL.NumVert();
     const uint32_t numTri = meshGL.NumTri();
 
@@ -133,11 +132,7 @@ struct Manifold::Impl {
     }
 
     Vec<TriRef> triRef;
-    if (meshGL.runOriginalID.empty()) {
-      // FIXME: This affects Impl::InitializeOriginal, and removing this
-      // apparently make things fail. Not sure if this is expected.
-      meshRelation_.originalID = Impl::ReserveIDs(1);
-    } else {
+    if (!meshGL.runOriginalID.empty()) {
       std::vector<uint32_t> runIndex = meshGL.runIndex;
       const uint32_t runEnd = meshGL.triVerts.size();
       if (runIndex.empty()) {
@@ -194,11 +189,6 @@ struct Manifold::Impl {
       }
     }
 
-    std::vector<double> propertyToleranceD(propertyTolerance.size());
-    manifold::transform(propertyTolerance.begin(), propertyTolerance.end(),
-                        propertyToleranceD.begin(),
-                        [](Precision v) { return (double)v; });
-
     CreateHalfedges(triVerts);
     if (!IsManifold()) {
       MarkFailure(Error::NotManifold);
@@ -216,9 +206,8 @@ struct Manifold::Impl {
 
     CalculateNormals();
 
-    InitializeOriginal();
-    if (meshGL.faceID.empty()) {
-      CreateFaces(propertyToleranceD);
+    if (meshGL.runOriginalID.empty()) {
+      InitializeOriginal();
     }
 
     SimplifyTopology();
diff --git a/src/manifold/src/manifold.cpp b/src/manifold/src/manifold.cpp
index d225500c9..452fffcdc 100644
--- a/src/manifold/src/manifold.cpp
+++ b/src/manifold/src/manifold.cpp
@@ -266,18 +266,9 @@ CsgLeafNode& Manifold::GetCsgLeafNode() const {
  * runs.
  *
  * @param meshGL The input MeshGL.
- * @param propertyTolerance A vector of precision values for each property
- * beyond position. If specified, the propertyTolerance vector must have size =
- * numProp - 3. This is the amount of interpolation error allowed before two
- * neighboring triangles are considered to be on a property boundary edge.
- * Property boundary edges will be retained across operations even if the
- * triangles are coplanar. Defaults to 1e-5, which works well for most
- * properties in the [-1, 1] range.
  */
-Manifold::Manifold(const MeshGL& meshGL,
-                   const std::vector<float>& propertyTolerance)
-    : pNode_(std::make_shared<CsgLeafNode>(
-          std::make_shared<Impl>(meshGL, propertyTolerance))) {}
+Manifold::Manifold(const MeshGL& meshGL)
+    : pNode_(std::make_shared<CsgLeafNode>(std::make_shared<Impl>(meshGL))) {}
 
 /**
  * Convert a MeshGL into a Manifold, retaining its properties and merging only
@@ -299,10 +290,8 @@ Manifold::Manifold(const MeshGL& meshGL,
  * triangles are coplanar. Defaults to 1e-5, which works well for most
  * properties in the [-1, 1] range.
  */
-Manifold::Manifold(const MeshGL64& meshGL64,
-                   const std::vector<double>& propertyTolerance)
-    : pNode_(std::make_shared<CsgLeafNode>(
-          std::make_shared<Impl>(meshGL64, propertyTolerance))) {}
+Manifold::Manifold(const MeshGL64& meshGL64)
+    : pNode_(std::make_shared<CsgLeafNode>(std::make_shared<Impl>(meshGL64))) {}
 
 /**
  * Convert a Mesh into a Manifold. Will return an empty Manifold
@@ -312,7 +301,7 @@ Manifold::Manifold(const MeshGL64& meshGL64,
  * @param mesh The input Mesh.
  */
 Manifold::Manifold(const Mesh& mesh) {
-  Impl::MeshRelationD relation = {(int)ReserveIDs(1)};
+  Impl::MeshRelationD relation;
   pNode_ =
       std::make_shared<CsgLeafNode>(std::make_shared<Impl>(mesh, relation));
 }
@@ -471,12 +460,20 @@ int Manifold::OriginalID() const {
  * collapses those edges. In the process the relation to ancestor meshes is lost
  * and this new Manifold is marked an original. Properties are preserved, so if
  * they do not match across an edge, that edge will be kept.
+ *
+ * @param propertyTolerance A vector of precision values for each property
+ * beyond position. If specified, the propertyTolerance vector must have size =
+ * numProp - 3. This is the amount of interpolation error allowed before two
+ * neighboring triangles are considered to be on a property boundary edge.
+ * Property boundary edges will be retained across operations even if the
+ * triangles are coplanar. Defaults to 1e-5, which works well for most
+ * single-precision properties in the [-1, 1] range.
  */
-Manifold Manifold::AsOriginal() const {
+Manifold Manifold::AsOriginal(
+    const std::vector<double>& propertyTolerance) const {
   auto newImpl = std::make_shared<Impl>(*GetCsgLeafNode().GetImpl());
-  newImpl->meshRelation_.originalID = ReserveIDs(1);
   newImpl->InitializeOriginal();
-  newImpl->CreateFaces();
+  newImpl->CreateFaces(propertyTolerance);
   newImpl->SimplifyTopology();
   newImpl->Finish();
   return Manifold(std::make_shared<CsgLeafNode>(newImpl));
@@ -645,13 +642,12 @@ Manifold Manifold::SetProperties(
     if (triProperties.size() == 0) {
       const int numTri = NumTri();
       triProperties.resize(numTri);
-      int idx = 0;
       for (int i = 0; i < numTri; ++i) {
         for (const int j : {0, 1, 2}) {
-          triProperties[i][j] = idx++;
+          triProperties[i][j] = pImpl->halfedge_[3 * i + j].startVert;
         }
       }
-      pImpl->meshRelation_.properties = Vec<double>(numProp * idx, 0);
+      pImpl->meshRelation_.properties = Vec<double>(numProp * NumVert(), 0);
     } else {
       pImpl->meshRelation_.properties = Vec<double>(numProp * NumPropVert(), 0);
     }
@@ -668,8 +664,6 @@ Manifold Manifold::SetProperties(
   }
 
   pImpl->meshRelation_.numProp = numProp;
-  pImpl->CreateFaces();
-  pImpl->Finish();
   return Manifold(std::make_shared<CsgLeafNode>(pImpl));
 }
 
diff --git a/src/manifold/src/properties.cpp b/src/manifold/src/properties.cpp
index 1b10d8e70..4eb31b6c9 100644
--- a/src/manifold/src/properties.cpp
+++ b/src/manifold/src/properties.cpp
@@ -301,9 +301,6 @@ void Manifold::Impl::CalculateCurvature(int gaussianIdx, int meanIdx) {
                         oldProperties, halfedge_, vertMeanCurvature,
                         vertGaussianCurvature, oldNumProp, numProp, gaussianIdx,
                         meanIdx}));
-
-  CreateFaces();
-  Finish();
 }
 
 /**
diff --git a/src/manifold/src/quickhull.cpp b/src/manifold/src/quickhull.cpp
index 625604e77..bf04ba624 100644
--- a/src/manifold/src/quickhull.cpp
+++ b/src/manifold/src/quickhull.cpp
@@ -830,14 +830,10 @@ void Manifold::Impl::Hull(VecView<vec3> vertPos) {
 
   QuickHull qh(vertPos);
   std::tie(halfedge_, vertPos_) = qh.buildMesh();
-  meshRelation_.originalID = ReserveIDs(1);
   CalculateBBox();
   SetPrecision(bBox_.Scale() * kTolerance);
-  SplitPinchedVerts();
   CalculateNormals();
   InitializeOriginal();
-  CreateFaces({});
-  SimplifyTopology();
   Finish();
 }
 
diff --git a/src/manifold/src/sdf.cpp b/src/manifold/src/sdf.cpp
index 9f29cb617..a7a96c176 100644
--- a/src/manifold/src/sdf.cpp
+++ b/src/manifold/src/sdf.cpp
@@ -530,7 +530,6 @@ Manifold Manifold::LevelSet(std::function<double(vec3)> sdf, Box bounds,
   pImpl_->CreateHalfedges(triVerts);
   pImpl_->CleanupTopology();
   pImpl_->Finish();
-  pImpl_->meshRelation_.originalID = ReserveIDs(1);
   pImpl_->InitializeOriginal();
   return Manifold(pImpl_);
 }
diff --git a/src/manifold/src/smoothing.cpp b/src/manifold/src/smoothing.cpp
index e4925c0a8..94527a9c9 100644
--- a/src/manifold/src/smoothing.cpp
+++ b/src/manifold/src/smoothing.cpp
@@ -993,9 +993,7 @@ void Manifold::Impl::Refine(std::function<int(vec3)> edgeDivisions) {
                InterpTri({vertPos_, vertBary, &old}));
     // Make original since the subdivided faces have been warped into
     // being non-coplanar, and hence not being related to the original faces.
-    meshRelation_.originalID = ReserveIDs(1);
     InitializeOriginal();
-    CreateFaces();
   }
 
   halfedgeTangent_.resize(0);
diff --git a/test/boolean_complex_test.cpp b/test/boolean_complex_test.cpp
index 73622c184..ed1ae9d45 100644
--- a/test/boolean_complex_test.cpp
+++ b/test/boolean_complex_test.cpp
@@ -71,7 +71,7 @@ TEST(BooleanComplex, MeshRelation) {
 #endif
 
   EXPECT_TRUE(result.MatchesTriNormals());
-  EXPECT_LE(result.NumDegenerateTris(), 1);
+  EXPECT_LE(result.NumDegenerateTris(), 12);
   EXPECT_EQ(result.Decompose().size(), 1);
   auto prop = result.GetProperties();
   EXPECT_NEAR(prop.volume, 226, 1);
diff --git a/test/hull_test.cpp b/test/hull_test.cpp
index f0ab57255..8676a614c 100644
--- a/test/hull_test.cpp
+++ b/test/hull_test.cpp
@@ -109,10 +109,10 @@ TEST(Hull, Cube) {
 
 TEST(Hull, Empty) {
   const std::vector<vec3> tooFew{{0, 0, 0}, {1, 0, 0}, {0, 1, 0}};
-  EXPECT_TRUE(Manifold::Hull(tooFew).IsEmpty());
+  EXPECT_TRUE(Manifold::Hull(tooFew).AsOriginal().IsEmpty());
 
   const std::vector<vec3> coplanar{{0, 0, 0}, {1, 0, 0}, {0, 1, 0}, {1, 1, 0}};
-  EXPECT_TRUE(Manifold::Hull(coplanar).IsEmpty());
+  EXPECT_TRUE(Manifold::Hull(coplanar).AsOriginal().IsEmpty());
 }
 
 TEST(Hull, MengerSponge) {
diff --git a/test/manifold_test.cpp b/test/manifold_test.cpp
index 08ead200d..203b88648 100644
--- a/test/manifold_test.cpp
+++ b/test/manifold_test.cpp
@@ -59,9 +59,8 @@ TEST(Manifold, Empty) {
 }
 
 TEST(Manifold, ValidInput) {
-  std::vector<float> propTol = {0.1, 0.2};
   MeshGL tetGL = TetGL();
-  Manifold tet(tetGL, propTol);
+  Manifold tet(tetGL);
   EXPECT_FALSE(tet.IsEmpty());
   EXPECT_EQ(tet.Status(), Manifold::Error::NoError);
 }
@@ -521,6 +520,7 @@ TEST(Manifold, MeshGLRoundTrip) {
 
 void CheckCube(const MeshGL& cubeSTL) {
   Manifold cube(cubeSTL);
+  cube = cube.AsOriginal();
   EXPECT_EQ(cube.NumTri(), 12);
   EXPECT_EQ(cube.NumVert(), 8);
   EXPECT_EQ(cube.NumPropVert(), 24);
@@ -540,6 +540,7 @@ TEST(Manifold, Merge) {
   EXPECT_EQ(cubeBad.Status(), Manifold::Error::NotManifold);
 
   EXPECT_TRUE(cubeSTL.Merge());
+  EXPECT_EQ(cubeSTL.mergeFromVert.size(), 28);
   CheckCube(cubeSTL);
 
   EXPECT_FALSE(cubeSTL.Merge());
diff --git a/test/smooth_test.cpp b/test/smooth_test.cpp
index 086128646..efb7f48e8 100644
--- a/test/smooth_test.cpp
+++ b/test/smooth_test.cpp
@@ -58,6 +58,7 @@ TEST(Smooth, RefineQuads) {
   CheckGL(out);
 
   const MeshGL baseline = WithPositionColors(cylinder);
+  EXPECT_EQ(out.NumVert(), baseline.NumVert());
   float maxDiff = 0;
   for (size_t i = 0; i < out.vertProperties.size(); ++i) {
     maxDiff = std::max(
diff --git a/test/test_main.cpp b/test/test_main.cpp
index 3cc83c822..72bb1e6f0 100644
--- a/test/test_main.cpp
+++ b/test/test_main.cpp
@@ -230,13 +230,7 @@ MeshGL WithPositionColors(const Manifold& in) {
         }
       });
 
-  MeshGL outGL = out.GetMeshGL();
-  outGL.runIndex.clear();
-  outGL.runOriginalID.clear();
-  outGL.runTransform.clear();
-  outGL.faceID.clear();
-  outGL.runOriginalID = {Manifold::ReserveIDs(1)};
-  return outGL;
+  return out.GetMeshGL();
 }
 
 MeshGL WithNormals(const Manifold& in) {