GNEX • LDS • TNMA • TNMC • Specialty Threadforms
We specialize in legacy and obsolete carbide threading inserts, supporting discontinued tool systems and specialty threadforms including GNEX, LDS, TNMA, and TNMC. Whether you’re maintaining classic equipment or rescuing a custom process, our inventory and cross-reference network bring the past back online.
Why Legacy Threading Still Matters
Modern catalogs move fast. Machines don’t.
Thousands of shops still rely on proven threading systems that were never meant to vanish. Our mission is to keep those systems alive with:
- NOS (New Old Stock) threading inserts
- Discontinued and specialty geometries
- Cross-referenced modern equivalents
- Technical guidance
Legacy Insert Families We Support
GNEX — External Threading Inserts
Classic external threading geometry for steel, stainless, and alloy work. Common sizes include GNEX-3, GNEX-4, and GNEX-5. Compatible replacements available.
LDS — Internal Threading Inserts
Compact internal threading for tight bores and legacy boring systems. We stock LDS-3, LDS-4, and related profiles.
TNMA — Turning & Threading Inserts
Negative-rake triangular inserts for rugged turning and threading operations. Popular formats include TNMA-43, TNMA-332, and TNMA-431.
TNMC — Precision Threading Inserts
Positive-edge triangular inserts optimized for fine pitch and finish threading. Commonly sourced as TNMC-332, TNMC-43, and equivalent insert codes.
Specialty & Obsolete Threadforms
We routinely supply tooling for:
- Unified threads (UNC / UNF)
- Metric threadforms
- Pipe threads (NPT / BSP)
- ACME + MOD ACME & trapezoidal forms
- Custom & proprietary legacy profiles
If your part number doesn’t appear in any modern catalog — you are exactly where you should be.
Cross-Reference & Replacement Support
Send us your obsolete part number, print code, or a clear photo of the insert. Our technical team can help identify:
- Direct replacements
- Compatible modern ISO equivalents
- Alternative geometries that preserve thread integrity
Why Great Lakes Carbide Supply
- Hard-to-find legacy threading inserts in stock
- Trusted Canadian distributor
- NOS and modern equivalent sourcing
- Fast shipping across North America
- Technical support
Threading Insert Brands & Compatibility
We supply carbide threading inserts from trusted manufacturers including Carboline and Techmet, along with compatible equivalents for discontinued tooling systems from Kennametal, Sandvik, Iscar, Valenite, and other legacy OEMs.
Request a Quote or Cross-Reference
Looking for a specific GNEX, LDS, TNMA, or TNMC insert?
Email your part number, photo, or print. We’ll check stock or provide a compatible equivalent.