Selection Guide3 min read

Do You Need Engraved Ejector Blades for Batch Traceability?

Key Takeaway: For multi-cavity molds with rib features, engraved blades enable per-cavity traceability at the rib ejection point — the only location where a marking tool (blade) is already in contact with the part surface.

Why Blade Engraving for Traceability

In molds where ribs are the primary ejection features, ejector blades are already in contact with the part surface. Adding engraving to these blades provides traceability marking without adding additional pins solely for marking purposes. This saves space in the mold and reduces the total pin count.

Implementation Strategy

High-visibility ribs: Engrave the cavity number on the blade ejecting the most visible/accessible rib
Date code: Use a separate round ejector pin with date code insert (blades are too narrow for insert pockets in most cases)
Quality correlation: Map cavity numbers to production quality data for per-cavity SPC analysis

Frequently Asked Questions

Can I use engraved blades for date codes?+

Date code inserts require a minimum tip width of 5mm. Most blade applications use widths of 2–4mm, which is too narrow for inserts. Use a separate round ejector pin with date code insert for date marking.

How many spare engraved blades should I keep?+

For production molds: minimum 1 complete spare set per mold. For high-volume production (>500,000 cycles/year): 2 spare sets. Pre-order spares with the original blade order to ensure consistent engraving placement.