diff --git a/fusion_plating/fusion_plating_configurator/migrations/19.0.9.0.0/__init__.py b/fusion_plating/fusion_plating_configurator/migrations/19.0.9.0.0/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/fusion_plating/fusion_plating_configurator/migrations/19.0.9.0.0/post-migration.py b/fusion_plating/fusion_plating_configurator/migrations/19.0.9.0.0/post-migration.py
new file mode 100644
index 00000000..684e9816
--- /dev/null
+++ b/fusion_plating/fusion_plating_configurator/migrations/19.0.9.0.0/post-migration.py
@@ -0,0 +1,75 @@
+# -*- coding: utf-8 -*-
+# Copyright 2026 Nexa Systems Inc.
+# License OPL-1
+# Sub 2 — Part Data Model Overhaul. Runs on upgrade from < 19.0.9.0.0.
+# Idempotent (NULL / empty guards). Safe to re-run.
+
+import logging
+
+_logger = logging.getLogger(__name__)
+
+
+def migrate(cr, version):
+    if not version:
+        return  # Fresh install — nothing to migrate
+
+    _logger.info("Sub 2: starting part-data-model migration to %s", version)
+
+    # Step 1: Backfill part_number from name where empty
+    cr.execute("""
+        UPDATE fp_part_catalog
+        SET    part_number = name
+        WHERE  part_number IS NULL OR part_number = ''
+    """)
+    _logger.info("Sub 2: backfilled part_number on %d records", cr.rowcount)
+
+    # Step 2: Backfill revision with 'A' where empty
+    cr.execute("""
+        UPDATE fp_part_catalog
+        SET    revision = 'A'
+        WHERE  revision IS NULL OR revision = ''
+    """)
+    _logger.info("Sub 2: backfilled revision on %d records", cr.rowcount)
+
+    # Step 3: Split fp_sale_description_template.description into two columns
+    # Copy existing description into BOTH internal_description and
+    # customer_facing_description. Estimators split them later.
+    cr.execute("""
+        UPDATE fp_sale_description_template
+        SET    internal_description         = description,
+               customer_facing_description  = description
+        WHERE  description IS NOT NULL
+          AND  description <> ''
+          AND  (internal_description IS NULL OR internal_description = '')
+    """)
+    _logger.info(
+        "Sub 2: duplicated description into new columns on %d template rows",
+        cr.rowcount,
+    )
+
+    # Step 4: Backfill x_fc_internal_description on sale.order.line
+    # Copy the existing `name` (Odoo's line description) into internal so
+    # historical lines satisfy the required-field check when it flips.
+    cr.execute("""
+        UPDATE sale_order_line
+        SET    x_fc_internal_description = name
+        WHERE  x_fc_internal_description IS NULL OR x_fc_internal_description = ''
+    """)
+    _logger.info(
+        "Sub 2: backfilled x_fc_internal_description on %d SO lines",
+        cr.rowcount,
+    )
+
+    # Step 5: Default certificate_requirement to 'inherit' on any rows
+    # where it's NULL (shouldn't happen given Odoo default=, but defensive).
+    cr.execute("""
+        UPDATE fp_part_catalog
+        SET    certificate_requirement = 'inherit'
+        WHERE  certificate_requirement IS NULL
+    """)
+    _logger.info(
+        "Sub 2: defaulted certificate_requirement to 'inherit' on %d parts",
+        cr.rowcount,
+    )
+
+    _logger.info("Sub 2: migration complete")
diff --git a/fusion_plating/fusion_plating_configurator/migrations/__init__.py b/fusion_plating/fusion_plating_configurator/migrations/__init__.py
new file mode 100644
index 00000000..e69de29b