diff --git a/boards/management/commands/cleanfiles.py b/boards/management/commands/cleanfiles.py
deleted file mode 100644
--- a/boards/management/commands/cleanfiles.py
+++ /dev/null
@@ -1,36 +0,0 @@
-import os
-from boards.abstracts.constants import FILE_DIRECTORY
-
-from django.core.management import BaseCommand
-from django.db import transaction
-from boards.models import Attachment
-
-from neboard.settings import MEDIA_ROOT
-
-
-__author__ = 'neko259'
-
-THUMB_SIZE = (200, 150)
-
-
-class Command(BaseCommand):
-    help = 'Remove files whose models were deleted'
-
-    @transaction.atomic
-    def handle(self, *args, **options):
-        thumb_prefix = '.{}x{}'.format(*THUMB_SIZE)
-
-        count = 0
-        model_files = os.listdir(MEDIA_ROOT + FILE_DIRECTORY)
-        for file in model_files:
-            model_filename = file if thumb_prefix not in file else file.replace(
-                thumb_prefix, '')
-            found = Attachment.objects.filter(file=FILE_DIRECTORY + model_filename)\
-                .exists()
-
-            if not found:
-                print('Missing {}'.format(file))
-                os.remove(MEDIA_ROOT + FILE_DIRECTORY + file)
-                count += 1
-
-        print('Deleted {} attachment files.'.format(count))
diff --git a/boards/signals.py b/boards/signals.py
--- a/boards/signals.py
+++ b/boards/signals.py
@@ -1,4 +1,11 @@
 import re
+import os
+
+from django.db.models.signals import post_save, pre_save, pre_delete, \
+    post_delete
+from django.dispatch import receiver
+from django.utils import timezone
+
 from boards import thumbs
 from boards.mdx_neboard import get_parser
 
@@ -8,10 +15,7 @@ from boards.models.post import REGEX_NOT
         REGEX_GLOBAL_REPLY
 from boards.models.post.manager import post_import_deps
 from boards.models.user import Notification
-from django.db.models.signals import post_save, pre_save, pre_delete, \
-    post_delete
-from django.dispatch import receiver
-from django.utils import timezone
+from neboard.settings import MEDIA_ROOT
 
 
 THUMB_SIZES = ((200, 150),)
@@ -113,3 +117,16 @@ def rebuild_refmap(instance, **kwargs):
     for referenced_post in instance.refposts.all():
         referenced_post.build_refmap(excluded_ids=[instance.id])
         referenced_post.save(update_fields=['refmap'])
+
+
+@receiver(post_delete, sender=Attachment)
+def delete_file(instance, **kwargs):
+    if instance.is_internal():
+        file = MEDIA_ROOT + instance.file.name
+        os.remove(file)
+        if instance.mimetype in FILE_TYPES_IMAGE:
+            for size in THUMB_SIZES:
+                file_name_parts = instance.file.name.split('.')
+                thumb_file = MEDIA_ROOT + '{}.{}x{}.{}'.format(file_name_parts[0], *size, file_name_parts[1])
+                os.remove(thumb_file)
+