BEYOND YWMT16T304-ZM T9125 Carbide Turning Insert – CVD Coated 25° Rhombic Steel Finishing
YNMG160408-ZM T9125 (10pcs)
YNMG160404-ZM T9125 (10pcs)
Tungaloy YNMG160404-ZF T9125 Carbide Turning Insert – PVD Coated for Steel Semi-Finishing
YN / YW 25° Rhombic Negative Inserts — Ultra-Slim Profiling for Steel Finishing
YN 25° rhombic negative inserts provide the narrowest point angle in standard ISO turning geometry, making them the precision tool for ultra-slim profiling, contour finishing, and complex-shape work on steel where 35° / 55° / 80° geometries can't reach.
This catalog covers 4 SKUs in IC 9.525 mm and IC 16.5 mm sizes with T9125 grade — including 1 genuine Tungaloy YNMG insert plus 3 BEYOND house-brand equivalents using the same ISO YN/YW geometry and T9125-grade specifications.
Browse the full YN/YW 25° rhombic negative catalog, or jump to: Genuine Tungaloy · BEYOND Equivalents · ISO Code Decoder · FAQ.
About YN / YW 25° Rhombic Negative Inserts
The YN 25° rhombic (parallelogram) negative geometry is the most specialized insert shape in standard ISO turning. With a 25° point angle — narrower than 35° VN, 55° DN, or 80° CN — YN inserts provide exceptional clearance for ultra-slim profiling, intricate contouring, and small-diameter internal features that wider geometries can't reach.
Key advantages of the YN/YW 25° geometry:
- Maximum clearance for plunging, profiling, and contouring on long slender shafts and internal bores
- Lowest radial cutting forces of any turning geometry — minimizes vibration and chatter on flexible workpieces
- Ideal for Swiss-type lathes where the small tool envelope and high RPM demand minimal radial forces
- 4 cutting edges per insert (rhombic shape) — better economy than triangular TN (3 edges) at the same feed rates
- YN tolerance = standard ISO tolerance. YW tolerance = tighter (precision-ground for finishing)
Tungaloy (Iwate, Japan) supplies the YN family primarily in YNMG geometry with Z-class chipbreakers (ZM for medium, ZF for finishing). BEYOND (our house brand) supplies compatible YNMG and YWMT inserts at significantly lower cost — both lines use the T9125 CVD/PVD grade for steel profiling.
Genuine Tungaloy (1 SKU)
One genuine Tungaloy insert in this catalog — the YNMG160404-ZF T9125 PVD-coated steel finishing insert.
Tungaloy YNMG160404-ZF T9125 — Steel Finishing
PVD-coated Tungaloy original with ZF (finishing) chipbreaker for the final pass on alloy steel shafts. Achieves Ra 0.4–0.8 µm at low feeds. Genuine Tungaloy Japan in factory packaging.
BEYOND House-Brand Equivalents (3 SKUs)
Three BEYOND inserts in this collection use the same ISO 25° rhombic geometry and T9125-grade specifications as Tungaloy's YN family. Manufactured to ISO 1832 standards, they are drop-in compatible with the same DVJNR/L, DVVNN, and A25S tool holders — typically priced 30–50% lower.
YNMG160408-ZM T9125 (10pcs) — BEYOND
BEYOND 10-pack with ZM (medium) chipbreaker for steel profiling and light roughing. 0.8 mm corner radius balances edge strength and finish. ISO-compatible with Tungaloy YNMG inserts.
YNMG160404-ZM T9125 (10pcs) — BEYOND
BEYOND 10-pack with sharp 0.4 mm corner radius for steel finishing profiling. ZM chipbreaker with sharp edge geometry for cleaner cuts at low feeds.
BEYOND YWMT16T304-ZM T9125 — Large IC Steel Finishing
BEYOND large-IC insert (16.5 mm edge length) with 7° positive relief for low radial forces. Ideal for slender workpiece profiling and internal boring where vibration is a concern.
ISO Code Decoder — YN / YW / YWMT Naming
The Y-shape geometry uses the following ISO 1832 code structure. This decoder applies to all YN, YW, YNMG, YWMT, YNGG, YWGG inserts across Tungaloy, BEYOND, and other brands:
| Code | Meaning | Options |
|---|---|---|
| Y | Insert shape (parallelogram) | Y = 25° rhombic, 35° lead |
| N / W | Relief angle (clearance) | N = 0° (no relief, sharp). W = 7° positive relief (lower cutting forces) |
| M | Tolerance class | M = medium tolerance (standard ISO) |
| G | Hole + chipbreaker | G = cylindrical hole + chipbreaker on both faces |
| T (in YWMT) | Insert thickness designation | T = 3.97 mm (1/6" imperial) |
| 16 / 04 / 04 | Dimensions (IC × thickness × corner radius) | 16 = 9.525 mm IC. 04 = thickness code. 04 = 0.4 mm radius. 16.5 (in YWMT16T304) = 16.5 mm edge length |
| ZM | Chipbreaker family | Z = zero/finishing-class breaker family. ZM = medium, ZF = finishing |
YN 25° Rhombic Negative — Typical Applications
The YN 25° geometry is purpose-built for specialized operations where standard geometries can't reach:
Ultra-Slim Profiling
Forming deep profiles with steep walls — the narrow 25° point angle provides clearance for transitions where 35° VN or 55° DN would rub.
Internal Boring & Small Diameters
Internal profiling and finishing on small-diameter bores where the small tool envelope demands minimal radial forces.
Swiss-Type Lathe Profiling
High-precision profiling on Swiss-type lathes for medical, electronics, and watch components where the small tool envelope and high RPM demand minimal radial forces.
Slender Shaft Turning
Turning long, slender shafts (L/D > 10:1) where wider geometries cause vibration and chatter. YN's low radial forces are ideal for flexible workpieces.
Mirror Finish Steel Profiling
ZF (finishing) chipbreaker variants achieve Ra 0.4–0.8 µm on alloy steel profiles for hydraulic, sealing, and bearing-seat surfaces.
Precision Mold & Die Work
Forming precision profiles on mold and die components where intricate contours demand the narrowest possible geometry.
Cross-Brand Comparison — Tungaloy vs BEYOND YN/YW Inserts
This collection is unique: it contains 1 genuine Tungaloy SKU and 3 BEYOND house-brand equivalents using identical ISO geometry. The table below compares the four SKUs side-by-side.
| SKU | Brand | Geometry | IC | Corner Radius | Chipbreaker | Grade / Coating | Best For |
|---|---|---|---|---|---|---|---|
| YNMG160404-ZF | Tungaloy | YNMG (rhombic, 0° relief) | 9.525 mm | 0.4 mm | ZF (finishing) | T9125 PVD TiAlN | Steel finishing, mirror surface |
| YNMG160404-ZM | BEYOND | YNMG (rhombic, 0° relief) | 9.525 mm | 0.4 mm | ZM (medium) | T9125 CVD | Steel finishing profiling |
| YNMG160408-ZM | BEYOND | YNMG (rhombic, 0° relief) | 9.525 mm | 0.8 mm | ZM (medium) | T9125 CVD | Steel medium profiling |
| YWMT16T304-ZM | BEYOND | YWMT (rhombic, 7° positive relief) | 16.5 mm | 0.4 mm | ZM (medium) | T9125 CVD | Slender shafts, internal boring |
For the broader Tungaloy negative family, see Tungaloy CNMG / DNMG / WNMG Negative Turning Inserts.
How to Choose the Right YN / YW Insert
Selecting the correct YN 25° rhombic insert involves four decisions:
- Relief angle → YN vs YW: YN = 0° relief (stronger edge, sharper profile). YW = 7° positive relief (lower radial forces, better for slender workpieces).
- Chipbreaker → ZM vs ZF: ZM = medium chipbreaker for profiling and light roughing. ZF = finishing chipbreaker for final-pass mirror finishes.
- IC size → Tool holder: IC 9.525 mm (YNMG 16) fits standard 16 mm seats. IC 16.5 mm (YWMT 16) fits larger 22 mm seats for heavy-duty holders.
- Brand → Tungaloy vs BEYOND: Choose Genuine Tungaloy for OEM-spec assurance and brand authenticity. Choose BEYOND for 30–50% cost savings on ISO-compatible equivalents.
Tip: For a single-SKU starter pack, choose the YNMG160408-ZM T9125 (10pcs) BEYOND pack as a versatile general-purpose profiling insert. For OEM-spec finishing, choose the Tungaloy YNMG160404-ZF T9125.
Frequently Asked Questions
What's the difference between Tungaloy and BEYOND inserts in this collection?
This collection contains a mix: 1 genuine Tungaloy SKU (YNMG160404-ZF T9125 PVD) and 3 BEYOND house-brand equivalents (YNMG160408-ZM, YNMG160404-ZM, YWMT16T304-ZM T9125). Both lines use the same ISO 1832 geometry codes and are drop-in compatible with the same DVJNR/L, DVVNN, and A25S tool holders. The key differences are coating technology (Tungaloy PVD TiAlN vs BEYOND CVD TiCN-Al₂O₃), edge preparation, and price (BEYOND is typically 30–50% lower than Tungaloy equivalent).
When should I use a 25° YN insert instead of 35° VN or 55° DN?
The YN 25° geometry is the most specialized of all turning geometries. It provides maximum clearance for ultra-slim profiling and intricate contour work that 35° VN, 55° DN, or 80° CN can't reach without rubbing. However, YN has the weakest cutting-edge strength of all geometries — so it's reserved for profiling and finishing, not heavy roughing. Use YN for ultra-slim profiling, internal boring, slender shafts, and Swiss-type lathe work. Use VN for general profiling, DN for profiling+light roughing, CN for heavy roughing.
What is the Z-class chipbreaker system?
The Z-class chipbreakers (ZM, ZF, ZR, etc.) are Tungaloy's and BEYOND's finishing-class chipbreaker family designed for low-feed, high-surface-finish operations on steel and stainless. ZM = medium (profiling, light roughing). ZF = finishing (final-pass mirror finishes). The Z-class geometry provides a sharper cutting edge with controlled chip flow at feeds typically below 0.20 mm/rev. Z-class inserts complement the heavier T-class (TM, TS) and TH-class chipbreakers used in medium and heavy turning.
What does the "W" in YWMT mean?
The "W" in YWMT designates a 7° positive relief angle, which provides lower radial cutting forces compared to the standard YN (0° relief). The W variant is preferred for slender workpieces, internal boring, and Swiss-type lathe work where vibration and chatter are concerns. The trade-off is slightly reduced edge strength — YW inserts are not recommended for interrupted cuts or heavy roughing. YWMT (BEYOND's house brand) follows the same ISO designation.
Are the BEYOND inserts the same quality as Tungaloy?
BEYOND inserts are manufactured to ISO 1832 standards and use comparable carbide substrates and coating technology (T9125 grade CVD/PVD with TiCN-Al₂O₃ or TiAlN coatings). The key differences are: (1) BEYOND uses CVD coating where Tungaloy uses PVD on some premium lines, (2) BEYOND edge preparation may be less refined than Tungaloy's OEM-specified edge hone, and (3) BEYOND doesn't carry the OEM brand-marking authentication. For OEM-spec work (aerospace, medical, certified automotive), genuine Tungaloy is recommended. For general industrial turning where ISO-geometry compatibility is sufficient, BEYOND offers significant cost savings.
What tool holder do I need for YN/YW 25° inserts?
YN 25° inserts (IC 9.525 mm) fit standard negative-rake tool holders designed for rhombic inserts. Common holders include Tungaloy DVJNR/L and DVVNN series for external turning, and A25S-DVUNR/L for internal boring. For YWMT (IC 16.5 mm), use larger holders such as SYJNR/L 2525M16. Browse our turning tool holder catalog for compatible options or contact us for holder recommendations.
Need Help Choosing the Right YN/YW Insert?
Tell us your workpiece material, profile complexity, and budget — we'll recommend the right Tungaloy, BEYOND, or combination solution within 24 hours.
Request a Quote WhatsApp a Specialist Download Grade Catalog Tungaloy Negative Family
Related Tungaloy & BEYOND Negative Insert Catalogs
Tungaloy VN 35° Diamond Negative
The wider 35° profiling alternative. VNMG 8 SKUs in stock for steel profiling with T9115/T9125/NS9530 grades.
Tungaloy DN 55° Diamond Negative
The 55° profiling family — pairs with YN/YW for full profiling workflows from ultra-slim to general profiling.
Tungaloy Negative Turning Inserts (Master)
Master catalog for all Tungaloy negative turning inserts — CNMG, DNMG, WNMG families.
BEYOND House Brand — Premium OEM-Alternative Inserts
Learn about BEYOND house-brand inserts: ISO 1832-compliant, OEM-grade carbide substrates, 30-50% lower cost than premium brands.
Turning Tool Holders — DVJNR / DVVNN
External turning tool holders compatible with YN 25° rhombic inserts. 16 mm and 22 mm seat sizes.
Sample Catalogs — Tungaloy & BEYOND
Free physical sample packs and grade cross-reference PDFs for qualified B2B inquiries.
Tungaloy, YN, YW, YNMG, YWMT, ZM, ZF, and T9125 are trademarks or grade designations of Tungaloy (Iwate, Japan / IMC Group). BEYOND is a house brand of cnchome-beyond.com — Super Industrial Trading Co., Ltd, Hangzhou, China. BEYOND inserts are manufactured to ISO 1832 standards and are not affiliated with Tungaloy.