diff --git a/lib/Slic3r/Fill.pm b/lib/Slic3r/Fill.pm
index 80edf518f..b624e8aa1 100644
--- a/lib/Slic3r/Fill.pm
+++ b/lib/Slic3r/Fill.pm
@@ -170,7 +170,7 @@ sub make_fill {
                             ? ($surface->surface_type == S_TYPE_TOP ? EXTR_ROLE_TOPSOLIDFILL : EXTR_ROLE_SOLIDFILL)
                             : EXTR_ROLE_FILL),
                     depth_layers => $surface->depth_layers,
-                    flow_spacing => $params->{flow_spacing},
+                    flow_spacing => $params->{flow_spacing} || $flow_spacing,
                 ), @paths,
             ],
         );