diff --git a/lib/Slic3r/Print/SupportMaterial.pm b/lib/Slic3r/Print/SupportMaterial.pm
index 4314e4fa6..d9b8b3313 100644
--- a/lib/Slic3r/Print/SupportMaterial.pm
+++ b/lib/Slic3r/Print/SupportMaterial.pm
@@ -8,7 +8,7 @@ use Slic3r::ExtrusionPath ':roles';
 use Slic3r::Flow ':roles';
 use Slic3r::Geometry qw(epsilon scale scaled_epsilon PI rad2deg deg2rad convex_hull);
 use Slic3r::Geometry::Clipper qw(offset diff union union_ex intersection offset_ex offset2
-    intersection_pl offset2_ex diff_pl);
+    intersection_pl offset2_ex diff_pl diff_ex);
 use Slic3r::Surface ':types';
 
 has 'print_config'      => (is => 'rw', required => 1);
@@ -782,7 +782,7 @@ sub generate_toolpaths {
             my $base_flow   = $_flow;
             
             # find centerline of the external loop/extrusions
-            my $to_infill = offset2_ex($base, +scaled_epsilon, -(scaled_epsilon + $_flow->scaled_width/2));
+            my $to_infill = offset2($base, +scaled_epsilon, -(scaled_epsilon + $_flow->scaled_width/2));
             
             my @paths = ();
             
@@ -796,6 +796,15 @@ sub generate_toolpaths {
                 # use the proper spacing for first layer as we don't need to align
                 # its pattern to the other layers
                 $filler->set_min_spacing($base_flow->spacing);
+                
+                # subtract brim so that it goes around the object fully (and support gets its own brim)
+                if ($self->print_config->brim_width > 0) {
+                    my $d = +scale $self->print_config->brim_width*2;
+                    $to_infill = diff_ex(
+                        $to_infill,
+                        offset($object->get_layer(0)->slices->polygons, $d),
+                    );
+                }
             } else {
                 # draw a perimeter all around support infill
                 # TODO: use brim ordering algorithm
@@ -806,10 +815,10 @@ sub generate_toolpaths {
                     mm3_per_mm  => $mm3_per_mm,
                     width       => $_flow->width,
                     height      => $layer->height,
-                ), map @$_, @$to_infill;
+                ), @$to_infill;
                 
                 # TODO: use offset2_ex()
-                $to_infill = offset_ex([ map @$_, @$to_infill ], -$_flow->scaled_spacing);
+                $to_infill = offset_ex($to_infill, -$_flow->scaled_spacing);
             }
             
             my $mm3_per_mm = $base_flow->mm3_per_mm;
diff --git a/xs/src/libslic3r/Fill/Fill.cpp b/xs/src/libslic3r/Fill/Fill.cpp
index c88a32514..555081616 100644
--- a/xs/src/libslic3r/Fill/Fill.cpp
+++ b/xs/src/libslic3r/Fill/Fill.cpp
@@ -1,3 +1,6 @@
+#define DEBUG
+#undef NDEBUG
+#include <cassert>
 #include <math.h>
 #include <stdio.h>
 
diff --git a/xs/src/libslic3r/Flow.cpp b/xs/src/libslic3r/Flow.cpp
index 6131534e7..a0cd62236 100644
--- a/xs/src/libslic3r/Flow.cpp
+++ b/xs/src/libslic3r/Flow.cpp
@@ -50,6 +50,11 @@ Flow::spacing() const {
     return this->width - OVERLAP_FACTOR * (this->width - min_flow_spacing);
 }
 
+void
+Flow::set_spacing(float spacing) {
+    this->width = Flow::_width_from_spacing(spacing, this->nozzle_diameter, this->height, this->bridge);
+}
+
 /* This method returns the centerline spacing between an extrusion using this
    flow and another one using another flow.
    this->spacing(other) shall return the same value as other.spacing(*this) */
diff --git a/xs/src/libslic3r/Flow.hpp b/xs/src/libslic3r/Flow.hpp
index fdfcac695..8284cc6d6 100644
--- a/xs/src/libslic3r/Flow.hpp
+++ b/xs/src/libslic3r/Flow.hpp
@@ -30,6 +30,7 @@ class Flow
         : width(_w), height(_h), nozzle_diameter(_nd), bridge(_bridge) {};
     float spacing() const;
     float spacing(const Flow &other) const;
+    void set_spacing(float spacing);
     double mm3_per_mm() const;
     coord_t scaled_width() const {
         return scale_(this->width);
@@ -48,7 +49,6 @@ class Flow
     static float _bridge_width(float nozzle_diameter, float bridge_flow_ratio);
     static float _auto_width(FlowRole role, float nozzle_diameter, float height);
     static float _width_from_spacing(float spacing, float nozzle_diameter, float height, bool bridge);
-    static float _spacing(float width, float nozzle_diameter, float height, float bridge_flow_ratio);
 };
 
 }
diff --git a/xs/src/libslic3r/Print.cpp b/xs/src/libslic3r/Print.cpp
index 36ce27a8a..118c73e96 100644
--- a/xs/src/libslic3r/Print.cpp
+++ b/xs/src/libslic3r/Print.cpp
@@ -163,6 +163,10 @@ Print::invalidate_state_by_config(const PrintConfigBase &config)
             || opt_key == "min_skirt_length"
             || opt_key == "ooze_prevention") {
             steps.insert(psSkirt);
+        } else if (opt_key == "brim_width") {
+            steps.insert(psBrim);
+            steps.insert(psSkirt);
+            osteps.insert(posSupportMaterial);
         } else if (opt_key == "brim_width"
             || opt_key == "interior_brim_width"
             || opt_key == "brim_connections_width") {
@@ -759,13 +763,17 @@ Print::brim_flow() const
        extruders and take the one with, say, the smallest index.
        The same logic should be applied to the code that selects the extruder during G-code
        generation as well. */
-    return Flow::new_from_config_width(
+    Flow flow = Flow::new_from_config_width(
         frPerimeter,
         width, 
         this->config.nozzle_diameter.get_at(this->regions.front()->config.perimeter_extruder-1),
         this->skirt_first_layer_height(),
         0
     );
+    
+    flow.set_spacing(unscale(Fill::adjust_solid_spacing(scale_(this->config.brim_width.value), scale_(flow.spacing()))));
+    
+    return flow;
 }
 
 Flow
@@ -844,8 +852,8 @@ Print::_make_brim()
         // perimeters because here we're offsetting outwards)
         append_to(loops, offset2(
             islands,
-            flow.scaled_width() + flow.scaled_spacing() * (i - 1.0 + 0.5),
-            flow.scaled_spacing() * -1.0,
+            flow.scaled_width() + flow.scaled_spacing() * (i - 1.5 + 0.5),
+            flow.scaled_spacing() * -0.5,
             100000,
             ClipperLib::jtSquare
         ));