Rectangular Ejector Pins for Large Mold
Blade-type ejector pins for narrow rib and deep slot ejection in large injection molds. 11 series covering M2 and H13 materials, JIS and 8mm head heights, standard and R-chamfered blade profiles.
Products — 11 Series
M2 Steel, JIS Head, Configurable Length
Standard blade with JIS head height. Custom length to 0.1 mm.
M2 Steel, 8mm Head, Configurable Length
Fixed 8mm head for structural support on long pins.
M2 Steel, 8mm Head, Configurable Width × Thickness
Custom blade dimensions for non-standard rib geometry.
M2 Steel, JIS Head, Crimping Blade
Crimped edge for enhanced resin grip during ejection.
M2 Steel, JIS Head, Configurable Width, Crimping
Custom width crimping blade for non-standard ribs.
M2 Steel, Blade Blanks
Un-headed blanks for custom head machining.
H13 Nitrided, Configurable Width × Thickness
For glass-filled and abrasive resins. 900+ HV surface.
H13 Nitrided, 8mm Head, Configurable Length
Fixed head height with nitrided wear resistance.
R-Chamfered, H13 Nitrided, Configurable
R-chamfer on blade edges reduces stress concentration.
R-Chamfered, M2 Steel, 8mm Head
R-chamfer in M2 high-hardness steel.
H13 Nitrided, Configurable Length
Standard blade width with nitrided surface.
Material Selection: M2 vs H13
The two material families serve different failure modes. Match your resin type to the correct steel grade:
| Property | M2 (SKH51) | H13 (SKD61) Nitrided |
|---|---|---|
| Core Hardness | 60–62 HRC | 44–48 HRC |
| Surface Hardness | ~750 HV (through-hardened) | 900–1,100 HV (nitrided layer) |
| Abrasion Resistance | Good | Excellent (glass-filled resins) |
| Deflection Resistance | Excellent (higher modulus) | Good |
| Thermal Fatigue Resistance | Moderate | Excellent |
| Best For | Unfilled resins, precision molds | Glass-filled, high-temp resins |
| Cost | $$ | $$$ |
Decision rule: If running glass-filled or mineral-filled resins, always choose H13 nitrided — the surface hardness advantage is decisive. For unfilled engineering plastics (ABS, PC, POM), M2 offers better deflection resistance at lower cost. For a detailed material comparison with lifecycle cost analysis, see our M2 vs H13 Rectangular Ejector Pins — Material Selection for Large Molds.
Application: When to Use Rectangular Ejector Pins
Narrow Rib Ejection
Ribs with width < 3 mm cannot accommodate round ejector pins. Rectangular pins match the rib cross-section for distributed ejection force without marks.
Blade geometry distributes ejection pressure across the full rib face, preventing the point-load whitening that round pins cause on thin ribs.
Recommended: M2 JIS Head — standard or configurable width
Deep Slot Ejection
Slots deeper than 5× width create high friction during ejection. Blade pins enter the slot and push from the full slot surface area.
The blade tip engages the full slot bottom surface, preventing the ejection-side drag marks that occur when round pins push asymmetrically on slot features.
Recommended: H13 Nitrided 8mm Head for deep slots in abrasive resins
Textured Surface Ejection
Textured ribs grip the mold during ejection. R-chamfered blades reduce stress concentration at blade edges, preventing part damage on textured surfaces.
The R-chamfer eliminates the sharp blade-edge-to-part contact that causes micro-cracking on textured or semi-crystalline parts during ejection.
Recommended: R-Chamfered H13 Nitrided
Sizing tip: Blade width should match rib width with 0.02–0.05 mm clearance per side. Blade thickness is determined by the plate pocket and required pin rigidity. For step-by-step blade sizing calculations, see our How to Size Rectangular Ejector Pins — Matching Blade to Rib Geometry.
Frequently Asked Questions
What is the maximum blade width and thickness available for large mold rectangular ejector pins?+
M2 or H13 — which material is better for rectangular ejector pins in glass-filled resins?+
What is the difference between JIS head and 8mm head rectangular ejector pins?+
Engineering Resources
Need Rectangular Ejector Pins?
Specify rib width, depth, resin type, and mold size. Custom blade dimensions available in 0.1 mm increments.