diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index 863c793e3..baca007cb 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -1602,14 +1602,17 @@ void GLCanvas3D::delete_selected()
     m_selection.erase();
 }
 
-void GLCanvas3D::ensure_on_bed(unsigned int object_idx)
+void GLCanvas3D::ensure_on_bed(unsigned int object_idx, bool allow_negative_z)
 {
+    if (allow_negative_z)
+        return;
+
     typedef std::map<std::pair<int, int>, double> InstancesToZMap;
     InstancesToZMap instances_min_z;
 
     for (GLVolume* volume : m_volumes.volumes) {
         if (volume->object_idx() == (int)object_idx && !volume->is_modifier) {
-            double min_z = volume->transformed_convex_hull_bounding_box().min(2);
+            double min_z = volume->transformed_convex_hull_bounding_box().min.z();
             std::pair<int, int> instance = std::make_pair(volume->object_idx(), volume->instance_idx());
             InstancesToZMap::iterator it = instances_min_z.find(instance);
             if (it == instances_min_z.end())
diff --git a/src/slic3r/GUI/GLCanvas3D.hpp b/src/slic3r/GUI/GLCanvas3D.hpp
index 6e7c26959..d9cd55e35 100644
--- a/src/slic3r/GUI/GLCanvas3D.hpp
+++ b/src/slic3r/GUI/GLCanvas3D.hpp
@@ -702,7 +702,7 @@ public:
     void select_all();
     void deselect_all();
     void delete_selected();
-    void ensure_on_bed(unsigned int object_idx);
+    void ensure_on_bed(unsigned int object_idx, bool allow_negative_z);
 
     bool is_gcode_legend_enabled() const { return m_gcode_viewer.is_legend_enabled(); }
     GCodeViewer::EViewType get_gcode_view_type() const { return m_gcode_viewer.get_view_type(); }
diff --git a/src/slic3r/GUI/GUI_ObjectList.cpp b/src/slic3r/GUI/GUI_ObjectList.cpp
index c06e90c91..df97cec5a 100644
--- a/src/slic3r/GUI/GUI_ObjectList.cpp
+++ b/src/slic3r/GUI/GUI_ObjectList.cpp
@@ -2708,7 +2708,7 @@ void ObjectList::delete_from_model_and_list(const std::vector<ItemForDelete>& it
                     if (obj->get_mesh_errors_count() == 0)
                         m_objects_model->DeleteWarningIcon(parent);
                 }
-                wxGetApp().plater()->canvas3D()->ensure_on_bed(item->obj_idx);
+                wxGetApp().plater()->canvas3D()->ensure_on_bed(item->obj_idx, printer_technology() != ptSLA);
             }
             else
                 m_objects_model->Delete(m_objects_model->GetItemByInstanceId(item->obj_idx, item->sub_obj_idx));
@@ -4075,7 +4075,7 @@ void ObjectList::set_extruder_for_selected_items(const int extruder) const
         const int obj_idx = type & itObject ? m_objects_model->GetIdByItem(item) :
                             m_objects_model->GetIdByItem(m_objects_model->GetTopParent(item));
 
-        wxGetApp().plater()->canvas3D()->ensure_on_bed(obj_idx);
+        wxGetApp().plater()->canvas3D()->ensure_on_bed(obj_idx, printer_technology() != ptSLA);
     }
 
     // update scene