Assessing the ability to grow with demand for the product, factories utilize automated CNC centers to produce these tools in massive quantities.
| Product Attribute | Specification Data |
| Diameter | 9.9mm |
| Tolerance Class | H7 |
| Material | Carbide Tip |
| Flute Type | Straight Flutes |
| Shank Type | Round Shank |
| Price | (*US dollars) 28.50 |
In 1774, John Wilkinson patented a boring mill that created accurate cylinders for steam engines. This invention changed history. Early machinists used carbon steel, but the introduction of tungsten carbide in 1927 revolutionized cutting speeds. Modern reamers like the 9.9mm H7 model utilize these principles through refined sintering processes.
The H7 tolerance specifies a hole diameter between 9.900 and 9.915 millimeters. Engineers rely on these digits for high-precision fits. Within the round shank design, the tool maintains concentricity during rotation within a lathe or milling machine.
Verified purchasers report the round shank fits perfectly into standard collets without slipping during high-speed operations. One buyer noted the 9.9mm tip leaves a mirror-like finish on aluminum workpieces. Another user mentioned the carbide edge stays sharp through 500 cycles.
Added Benefit
Carbide tips provide heat resistance that exceeds high-speed steel by 300 degrees Celsius. In the heat of friction, the tool remains rigid. This heat resistance allows for faster feed rates and reduced cycle times in busy shops.
Paper Trail
Manufacturers maintain ISO 9001 certifications to track the origin of every tungsten grain. Quality control logs document the grinding precision of each flute. Every batch undergoes inspection with digital micrometers to verify the H7 standard before shipping.
The Silent Geometry of the Straight Flute
Straight flutes effectively manage the flow of metal debris in specific applications. In shallow holes, the vertical channels guide chips away from the cutting face without the spiraling force of a twist drill. This linear path prevents the tool from pulling into the material or wandering off center. Because the flutes do not spiral, the reamer experiences less torsional stress during the final pass.
Thermal Expansion and Precision Clearance
Engineers specify the 9.9mm size to meet exact design requirements for specialized pins and shafts. In friction-heavy environments like engine blocks or aerospace components, maintaining precise dimensions is critical. Using a 9.9mm reamer ensures a specific clearance or interference fit required for the assembly to function as intended. This dimensioning allows for proper lubricant flow and accommodates thermal growth during operation. Trusted sources like the Machinery's Handbook confirm that H7 tolerances are the gold standard for these critical mechanical interfaces.
Global Carbide Availability
Modern logic controllers manage a significant portion of the grinding process for carbide tools. Supply chains for tungsten remain stable as recycling programs now provide a growing percentage of the raw material for new cutters. Demand for the 9.9mm size remains steady as robotics firms require precise shaft housings for automated assemblies. Specialized logistics networks carry these precision tools to workshops globally.
As of Sat 2026 Apr 04 11:51:22 AM EST: Spotlight Deals Chucking Reamer 9.9mm H7 Carbide Tip Straight Flutes Round Shank Lathe Machine Milling Cutter (*US dollars) 1.60 (Typically retails around *US dollars) 1 . 60
