Cincinnati’s Trusted Internal Keyway Milling Specialists
Southwest Ohio’s manufacturers and rebuilders—especially across Cincinnati—depend on our precision keyseating services to keep critical equipment operating flawlessly. At National Machine Tool Co., we deliver tailored internal keyway milling—from prototypes to production runs—without the delays and expense of broaching.
Why Cincinnati Businesses Choose Us
Local Expertise & Fast Turnaround: With our Cincinnati facility at E Galbraith Rd, you get quick lead times and guidance from a 4th-generation family-owned team.
On-site Accessibility: Serving clients in Sharonville, Blue Ash, Evendale, Forest Park, Hamilton County, and beyond.
Cutting-Edge Capability: Our precision keyseater handles blind and through bores, hardened steels, exotic alloys—without relief holes.
Flexible Volume Support: Whether you need one-off prototypes or repeat small runs, we’ve got you covered.
Service Capabilities & Specs
| Capability | Specification |
|---|---|
| Keyway Width | 1/8″ to 1.5″ |
| Max Bore Diameter | Up to 24″ OD |
| Material Types | Hardened steel (4140, 17-4, D2), Inconel, etc. |
| Part Weight | Up to 1,500 lbs |
| Blind Bore Compatibility | |
| Rush Turnaround | Available on Request |
Our Process
You upload your print or part specs
We engineer tooling and quote per-job – supporting manual/CNC setups for bores from under ½″ to over 6″ and keyway widths up to 2½″.
Precision machining at our Cincinnati shop
Receive finished parts or cutters with fast shipping or pickup
Industries We Serve in Cincinnati
Cincinnati’s thriving industrial sector demands precision tooling. Our keyseater tools support a variety of applications, including:
Aerospace
High-precision keyseating for aerospace parts and components.
Automotive
Machines capable of creating custom keyways for automotive transmission and engine parts.
Construction
Heavy-duty keyseating equipment suitable for demanding environments.
Energy & Utility
Machines for keyway cutting in power generation and utility equipment.
Ready for precision in Cincinnati?
Upload your drawing or part data for a flat-rate quote—fast, local, reliable.