diff --git a/lib/Slic3r/GUI/Plater.pm b/lib/Slic3r/GUI/Plater.pm
index ba527324a..bd1fa2964 100644
--- a/lib/Slic3r/GUI/Plater.pm
+++ b/lib/Slic3r/GUI/Plater.pm
@@ -437,7 +437,7 @@ sub changescale {
     my ($obj_idx, $object) = $self->selected_object;
     
     # max scale factor should be above 2540 to allow importing files exported in inches
-    my $scale = Wx::GetNumberFromUser("", "Enter the scale % for the selected object:", "Scale", $object->scale*100, 0, 5000, $self);
+    my $scale = Wx::GetNumberFromUser("", "Enter the scale % for the selected object:", "Scale", $object->scale*100, 0, 100000, $self);
     return if !$scale || $scale == -1;
     
     $self->{list}->SetItem($obj_idx, 2, "$scale%");
@@ -861,7 +861,7 @@ sub repaint {
     @{$parent->{object_previews}} = ();
     for my $obj_idx (0 .. $#{$parent->{objects}}) {
         my $object = $parent->{objects}[$obj_idx];
-        next unless $object->thumbnail;
+        next unless $object->thumbnail && @{$object->thumbnail->expolygons};
         for my $instance_idx (0 .. $#{$object->instances}) {
             my $instance = $object->instances->[$instance_idx];
             push @{$parent->{object_previews}}, [ $obj_idx, $instance_idx, $object->thumbnail->clone ];