diff --git a/lib/Slic3r/Fill/Concentric.pm b/lib/Slic3r/Fill/Concentric.pm
index 79e6d4a6d..4edd75ec6 100644
--- a/lib/Slic3r/Fill/Concentric.pm
+++ b/lib/Slic3r/Fill/Concentric.pm
@@ -28,7 +28,7 @@ sub fill_surface {
         $flow = Slic3r::Flow->new_from_spacing(
             spacing             => unscale($distance),
             nozzle_diameter     => $flow->nozzle_diameter,
-            layer_height        => $surface->thickness,
+            layer_height        => ($params{layer_height} or die "No layer_height supplied to fill_surface()"),
             bridge              => $flow->bridge,
         );
     }
diff --git a/t/fill.t b/t/fill.t
index 38b0360aa..dc1606a20 100644
--- a/t/fill.t
+++ b/t/fill.t
@@ -171,6 +171,7 @@ sub scale_points (@) { map [scale $_->[X], scale $_->[Y]], @_ }
 for my $pattern (qw(rectilinear honeycomb hilbertcurve concentric)) {
     my $config = Slic3r::Config->new_from_defaults;
     $config->set('fill_pattern', $pattern);
+    $config->set('solid_fill_pattern', $pattern);
     $config->set('perimeters', 1);
     $config->set('skirts', 0);
     $config->set('fill_density', 20);