diff --git a/src/libslic3r/SLAPrint.cpp b/src/libslic3r/SLAPrint.cpp
index 4e051724e..9ed89f16e 100644
--- a/src/libslic3r/SLAPrint.cpp
+++ b/src/libslic3r/SLAPrint.cpp
@@ -624,8 +624,10 @@ void SLAPrint::process()
             auto& lyrs = levels[h]; // this initializes a new record
             lyrs.emplace_back(oslices[i], po.m_instances);
 
+            float fh = float(double(h) * SCALING_FACTOR);
+
             // now for the public slice index:
-            SLAPrintObject::SliceRecord& sr = po.m_slice_index[h];
+            SLAPrintObject::SliceRecord& sr = po.m_slice_index[fh];
             // There should be only one slice layer for each print object
             assert(sr.model_slices_idx == EMPTY_SLICE);
             sr.model_slices_idx = i;
@@ -641,7 +643,9 @@ void SLAPrint::process()
                 auto& lyrs = levels[h];
                 lyrs.emplace_back(sslices[i], po.m_instances);
 
-                SLAPrintObject::SliceRecord& sr = po.m_slice_index[h];
+                float fh = float(double(h) * SCALING_FACTOR);
+
+                SLAPrintObject::SliceRecord& sr = po.m_slice_index[fh];
                 assert(sr.support_slices_idx == EMPTY_SLICE);
                 sr.support_slices_idx = i;
             }
diff --git a/src/libslic3r/SLAPrint.hpp b/src/libslic3r/SLAPrint.hpp
index c29c4d1cc..93b88a7df 100644
--- a/src/libslic3r/SLAPrint.hpp
+++ b/src/libslic3r/SLAPrint.hpp
@@ -92,8 +92,8 @@ public:
     // levels of the model in scaled-clipper coordinates. The levels correspond
     // to the z coordinate of the object coordinate system.
     struct SliceRecord {
-        using Key = long long;
-        inline static float scale_back(Key h) { return float(h * SCALING_FACTOR); }
+        using Key = float;
+//        inline static float scale_back(Key h) { return float(h * SCALING_FACTOR); }
 
         using Idx = size_t;
         static const Idx NONE = Idx(-1); // this will be the max limit of size_t