diff --git a/bin/scripts/name_parser/FontnameParser.py b/bin/scripts/name_parser/FontnameParser.py
index 2c5aff4..fbfc7ef 100644
--- a/bin/scripts/name_parser/FontnameParser.py
+++ b/bin/scripts/name_parser/FontnameParser.py
@@ -271,12 +271,34 @@ class FontnameParser:
             self.logger.error('====-< {:18} too long ({:2} > {:2}): {}'.format(entry_id, len(name), max_len, name))
         return name
 
+    def check_weights(self, font):
+        """ Check weight metadata for consistency """
+        # Some weights are hidden in styles
+        ignore_token = list(FontnameTools.known_widths) + list(FontnameTools.known_slopes)
+        ignore_token += [ m + s
+                        for s in list(FontnameTools.known_widths)
+                        for m in list(FontnameTools.known_modifiers) ]
+        restored_weight_token = [ w for w in self.style_token + self.weight_token if w not in ignore_token ]
+        weight = ''.join(restored_weight_token)
+        os2_weight = font.os2_weight
+        ps_weight = FontnameTools.weight_string_to_number(font.weight)
+        name_weight = FontnameTools.weight_string_to_number(weight)
+        if name_weight is None:
+            self.logger.error('Can not parse name for weight: {}'.format(restored_weight_token))
+            return
+        if abs(os2_weight - ps_weight) > 50 or abs(os2_weight - name_weight) > 50:
+            self.logger.warning('Possible problem with the weight metadata detected, check with --debug')
+        self.logger.debug('Weight approximations: OS2/PS/Name: {}/{}/{} (from {}/\'{}\'/\'{}\')'.format(
+            os2_weight, ps_weight, name_weight,
+            font.os2_weight, font.weight, weight))
+
     def rename_font(self, font):
         """Rename the font to include all information we found (font is fontforge font object)"""
         font.fondname = None
         font.fontname = self.psname()
         font.fullname = self.fullname()
         font.familyname = self.ps_familyname()
+        self.check_weights(font)
 
         # We have to work around several issues in fontforge:
         #
diff --git a/bin/scripts/name_parser/FontnameTools.py b/bin/scripts/name_parser/FontnameTools.py
index 0e664f6..52825b7 100644
--- a/bin/scripts/name_parser/FontnameTools.py
+++ b/bin/scripts/name_parser/FontnameTools.py
@@ -175,7 +175,7 @@ class FontnameTools:
         """Filter out characters that are not allowed in Postscript names"""
         # The name string must be restricted to the printable ASCII subset, codes 33 to 126,
         # except for the 10 characters '[', ']', '(', ')', '{', '}', '<', '>', '/', '%'
-        out = ""
+        out = ''
         for c in name:
             if c in '[](){}<>/%' or ord(c) < 33 or ord(c) > 126:
                 continue
@@ -247,6 +247,9 @@ class FontnameTools:
         'Light': ('Lt', 'Light'),
         ' ': (), # Just for CodeClimate :-/
     }
+    known_styles = [ # Keywords that end up as style (i.e. a RIBBI set)
+        'Bold', 'Italic', 'Regular', 'Normal'
+    ]
     known_widths = { # can take modifiers
         'Compressed': ('Cm', 'Comp'),
         'Extended': ('Ex', 'Extd'),
@@ -268,6 +271,51 @@ class FontnameTools:
         'Semi': ('Sm', 'Sem'),
         'Extra': ('X', 'Ext'),
     }
+    equivalent_weights = {
+        100: ('thin', 'hairline'),
+        200: ('extralight', 'ultralight'),
+        300: ('light', ),
+        350: ('semilight', ),
+        400: ('regular', 'normal', 'book', 'text', 'nord', 'retina'),
+        500: ('medium', ),
+        600: ('semibold', 'demibold', 'demi'),
+        700: ('bold', ),
+        800: ('extrabold', 'ultrabold'),
+        900: ('black', 'heavy', 'poster', 'extrablack', 'ultrablack'),
+    }
+
+    @staticmethod
+    def weight_string_to_number(w):
+        """ Convert a common string approximation to a PS/2 weight value """
+        if not len(w):
+            return 400
+        for num, strs in FontnameTools.equivalent_weights.items():
+            if w.lower() in strs:
+                return num
+        return None
+
+    @staticmethod
+    def weight_to_string(w):
+        """ Convert a PS/2 weight value to the common string approximation """
+        if w < 150:
+            str = 'Thin'
+        elif w < 250:
+            str = 'Extra-Light'
+        elif w < 350:
+            str = 'Light'
+        elif w < 450:
+            str = 'Regular'
+        elif w < 550:
+            str = 'Medium'
+        elif w < 650:
+            str = 'Semi-Bold'
+        elif w < 750:
+            str = 'Bold'
+        elif w < 850:
+            str = 'Extra-Bold'
+        else:
+            str = 'Black'
+        return str
 
     @staticmethod
     def is_keep_regular(basename):
@@ -342,8 +390,7 @@ class FontnameTools:
                 for s in list(FontnameTools.known_weights2) + list(FontnameTools.known_widths)
                 for m in list(FontnameTools.known_modifiers) + [''] if m != s
             ] + list(FontnameTools.known_weights1) + list(FontnameTools.known_slopes)
-        styles = [ 'Bold', 'Italic', 'Regular', 'Normal', ]
-        weights = [ w for w in weights if w not in styles ]
+        weights = [ w for w in weights if w not in FontnameTools.known_styles ]
         # Some font specialities:
         other = [
             '-', 'Book', 'For', 'Powerline',
@@ -355,7 +402,7 @@ class FontnameTools:
         ]
 
         ( style, weight_token ) = FontnameTools.get_name_token(style, weights)
-        ( style, style_token ) = FontnameTools.get_name_token(style, styles)
+        ( style, style_token ) = FontnameTools.get_name_token(style, FontnameTools.known_styles)
         ( style, other_token ) = FontnameTools.get_name_token(style, other)
         while 'Regular' in style_token and len(style_token) > 1:
             # Correct situation where "Regular" and something else is given
diff --git a/font-patcher b/font-patcher
index de29483..5efec62 100755
--- a/font-patcher
+++ b/font-patcher
@@ -6,7 +6,7 @@
 from __future__ import absolute_import, print_function, unicode_literals
 
 # Change the script version when you edit this script:
-script_version = "4.5.1"
+script_version = "4.5.2"
 
 version = "3.0.2"
 projectName = "Nerd Fonts"
@@ -444,6 +444,9 @@ class font_patcher:
 
         # Adjust flags that can not be changed via fontforge
         if re.search('\\.[ot]tf$', self.args.font, re.IGNORECASE) and re.search('\\.[ot]tf$', outfile, re.IGNORECASE):
+            if not os.path.isfile(outfile) or os.path.getsize(outfile) < 1:
+                logger.critical("Something went wrong and Fontforge did not generate the new font - look for messages above")
+                sys.exit(1)
             try:
                 source_font = TableHEADWriter(self.args.font)
                 dest_font = TableHEADWriter(outfile)
@@ -1144,7 +1147,7 @@ class font_patcher:
         if our_btb == hhea_btb:
             metrics = Metric.TYPO if use_typo else Metric.WIN # conforming font
         elif abs(our_btb - hhea_btb) / our_btb < 0.03:
-            logger.info("Font vertical metrics slightly off (%.1f%)", (our_btb - hhea_btb) / our_btb * 100.0)
+            logger.info("Font vertical metrics slightly off (%.1f)", (our_btb - hhea_btb) / our_btb * 100.0)
             metrics = Metric.TYPO if use_typo else Metric.WIN
         else:
             # Try the other metric