diff --git a/src/libslic3r/CSGMesh/SliceCSGMesh.hpp b/src/libslic3r/CSGMesh/SliceCSGMesh.hpp
index 95035b5ef..32f790546 100644
--- a/src/libslic3r/CSGMesh/SliceCSGMesh.hpp
+++ b/src/libslic3r/CSGMesh/SliceCSGMesh.hpp
@@ -46,6 +46,14 @@ std::vector<ExPolygons> slice_csgmesh_ex(
                 break;
             }
         }
+
+        for (ExPolygons &slice : ret) {
+            auto it = std::remove_if(slice.begin(), slice.end(), [](const ExPolygon &p){
+                return p.area() < double(SCALED_EPSILON) * double(SCALED_EPSILON);
+            });
+
+            slice.erase(it, slice.end());
+        }
     }
 
     return ret;
diff --git a/src/libslic3r/SLAPrint.cpp b/src/libslic3r/SLAPrint.cpp
index c3b90b192..b8000f384 100644
--- a/src/libslic3r/SLAPrint.cpp
+++ b/src/libslic3r/SLAPrint.cpp
@@ -792,13 +792,6 @@ bool SLAPrint::is_step_done(SLAPrintObjectStep step) const
 
 SLAPrintObject::SLAPrintObject(SLAPrint *print, ModelObject *model_object)
     : Inherited(print, model_object)
-//    , m_transformed_rmesh([this](TriangleMesh &obj) {
-////        obj = m_model_object->raw_mesh();
-////        if (!obj.empty()) {
-////            obj.transform(m_trafo);
-////        }
-//        obj = transformed_mesh_csg(*this);
-//    })
 {}
 
 SLAPrintObject::~SLAPrintObject() {}
@@ -1056,7 +1049,8 @@ const TriangleMesh& SLAPrintObject::pad_mesh() const
     return EMPTY_MESH;
 }
 
-const TriangleMesh &SLAPrintObject::get_mesh_to_print() const {
+const TriangleMesh &SLAPrintObject::get_mesh_to_print() const
+{
     const TriangleMesh *ret = nullptr;
 
     int s = SLAPrintObjectStep::slaposCount;
@@ -1068,7 +1062,7 @@ const TriangleMesh &SLAPrintObject::get_mesh_to_print() const {
     }
 
     if (!ret)
-        ret = &m_transformed_rmesh;
+        ret = &EMPTY_MESH;
 
     return *ret;
 }
@@ -1158,4 +1152,29 @@ void SLAPrint::StatusReporter::operator()(SLAPrint &         p,
     p.set_status(int(std::round(st)), msg, flags);
 }
 
+namespace csg {
+
+inline bool operator==(const VoxelizeParams &a, const VoxelizeParams &b)
+{
+    std::hash<Slic3r::csg::VoxelizeParams> h;
+    return h(a) == h(b);
+}
+
+VoxelGridPtr get_voxelgrid(const CSGPartForStep &part, const VoxelizeParams &p)
+{
+    VoxelGridPtr &ret = part.gridcache[p];
+
+    if (!ret) {
+        ret = mesh_to_grid(*csg::get_mesh(part),
+                           csg::get_transform(part),
+                           p.voxel_scale(),
+                           p.exterior_bandwidth(),
+                           p.interior_bandwidth());
+    }
+
+    return clone(*ret);
+}
+
+} // namespace csg
+
 } // namespace Slic3r
diff --git a/src/libslic3r/SLAPrint.hpp b/src/libslic3r/SLAPrint.hpp
index 084c78024..9ca610087 100644
--- a/src/libslic3r/SLAPrint.hpp
+++ b/src/libslic3r/SLAPrint.hpp
@@ -91,27 +91,7 @@ struct CSGPartForStep : public csg::CSGPart
 
 namespace csg {
 
-inline bool operator==(const VoxelizeParams &a, const VoxelizeParams &b)
-{
-    std::hash<Slic3r::csg::VoxelizeParams> h;
-    return h(a) == h(b);
-}
-
-inline VoxelGridPtr get_voxelgrid(const CSGPartForStep &part,
-                                  const VoxelizeParams &p)
-{
-    VoxelGridPtr &ret = part.gridcache[p];
-
-    if (!ret) {
-        ret = mesh_to_grid(*csg::get_mesh(part),
-                           csg::get_transform(part),
-                           p.voxel_scale(),
-                           p.exterior_bandwidth(),
-                           p.interior_bandwidth());
-    }
-
-    return clone(*ret);
-}
+VoxelGridPtr get_voxelgrid(const CSGPartForStep &part, const VoxelizeParams &p);
 
 } // namespace csg
 
@@ -372,7 +352,7 @@ private:
     std::vector<float>                      m_model_height_levels;
 
     // Caching the transformed (m_trafo) raw mesh of the object
-    TriangleMesh                            m_transformed_rmesh;
+//    TriangleMesh                            m_transformed_rmesh;
     
     struct SupportData
     {
diff --git a/src/libslic3r/SLAPrintSteps.cpp b/src/libslic3r/SLAPrintSteps.cpp
index b0efa31fa..52915a028 100644
--- a/src/libslic3r/SLAPrintSteps.cpp
+++ b/src/libslic3r/SLAPrintSteps.cpp
@@ -194,10 +194,6 @@ struct csg_inserter {
 void SLAPrint::Steps::mesh_assembly(SLAPrintObject &po)
 {
     po.m_mesh_to_slice.clear();
-
-    po.m_transformed_rmesh = po.m_model_object->raw_mesh();
-    po.m_transformed_rmesh.transform(po.trafo());
-
     csg::model_to_csgmesh(*po.model_object(), po.trafo(),
                           csg_inserter{po.m_mesh_to_slice, slaposAssembly},
                           csg::mpartsPositive | csg::mpartsNegative);
@@ -265,8 +261,11 @@ void SLAPrint::Steps::drill_holes(SLAPrintObject &po)
                           csg_inserter{po.m_mesh_to_slice, slaposDrillHoles},
                           csg::mpartsDrillHoles);
 
+    auto r = po.m_mesh_to_slice.equal_range(slaposDrillHoles);
+
     // update preview mesh
-    generate_preview(po, slaposDrillHoles);
+    if (r.first != r.second)
+        generate_preview(po, slaposDrillHoles);
 }
 
 template<class Pred>
@@ -374,8 +373,7 @@ void SLAPrint::Steps::slice_model(SLAPrintObject &po)
     auto  thr        = [this]() { m_print->throw_if_canceled(); };
     auto &slice_grid = po.m_model_height_levels;
 
-    Range csgrange = {po.m_mesh_to_slice.begin(), po.m_mesh_to_slice.end()};
-    po.m_model_slices = slice_csgmesh_ex(csgrange, slice_grid, params, thr);
+    po.m_model_slices = slice_csgmesh_ex(range(po.m_mesh_to_slice), slice_grid, params, thr);
 
     auto mit = slindex_it;
     for (size_t id = 0;
@@ -387,7 +385,8 @@ void SLAPrint::Steps::slice_model(SLAPrintObject &po)
     // We apply the printer correction offset here.
     apply_printer_corrections(po, soModel);
 
-    generate_preview(po, slaposObjectSlice);
+//    po.m_preview_meshes[slaposObjectSlice] = po.get_mesh_to_print();
+//    report_status(-2, "", SlicingStatus::RELOAD_SLA_PREVIEW);
 }
 
 static void filter_support_points_by_modifiers(
@@ -448,7 +447,7 @@ void SLAPrint::Steps::support_points(SLAPrintObject &po)
     if (!po.m_supportdata)
         po.m_supportdata =
             std::make_unique<SLAPrintObject::SupportData>(
-                po.m_preview_meshes[slaposObjectSlice]
+                po.get_mesh_to_print()
             );
 
     po.m_supportdata->input.zoffset = csgmesh_positive_bb(po.m_mesh_to_slice)