diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index 49604d138..24dd159a3 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -3751,7 +3751,8 @@ Linef3 GLCanvas3D::mouse_ray(const Point& mouse_pos)
 
 double GLCanvas3D::get_size_proportional_to_max_bed_size(double factor) const
 {
-    return factor * m_bed.build_volume().bounding_volume().max_size();
+    const BoundingBoxf& bbox = m_bed.build_volume().bounding_volume2d();
+    return factor * std::max(bbox.size()[0], bbox.size()[1]);
 }
 
 void GLCanvas3D::set_cursor(ECursorType type)