6-Flute 2-Step PCD Reamer with Shank – High-Precision Multi-Diameter Reaming

The 6-Flute 2-Step PCD Reamer with Shank is engineered for finishing dual-diameter (stepped) bores in a single controlled operation. In mass-production CNC environments, stepped hole accuracy depends on concentricity between diameters, stable cutting forces, and predictable tool wear. By combining a 2-step profile with six PCD cutting edges and an integrated shank, this tool delivers high rigidity, reduced vibration, and repeatable bore geometry—especially in aluminum, magnesium alloys, and composite materials where PCD provides major wear and finish advantages.

Aoshiji® Custom Tool supplies custom 2-step PCD reamers made to drawing, including step diameters, step distance, entry geometry, flute design, shank interface, and coolant strategy.

Overview

Stepped bores are common in engine blocks, cylinder heads, transmission housings, valve bodies, and precision structural components. Traditional production methods often require multiple reamers or a reamer + boring sequence, increasing tool changes and introducing alignment variation between diameters.

The 6-Flute 2-Step PCD Reamer with Shank solves this by integrating both finishing diameters into one rigid tool axis. The integrated shank design improves assembly stiffness and runout control compared to modular setups, supporting consistent hole size, roundness, and step relationship across long production runs.

PCD cutting edges provide excellent wear resistance and stable surface quality in non-ferrous machining. With proper setup and pre-hole control, the tool can deliver tight tolerance performance and mirror-like finishes in high-volume production.

Typical Use Cases

This tool is widely applied in:

Dual-diameter bore finishing in automotive engine blocks and cylinder heads
Transmission housings, gear cases, and die-cast aluminum components
Aerospace structural parts requiring stepped reaming with tight tolerances
Hydraulic valves, fluid transmission housings, and pneumatic components
EV motor housings and precision non-ferrous assemblies requiring coaxial step control

It is especially suitable where step-to-step alignment, surface finish, and production repeatability directly affect assembly quality.

Key Features

6-flute geometry for stable engagement, smooth cutting action, and improved bore roundness
2-step profile finishes dual diameters in one pass to reduce cycle time and tool changes
Integrated shank construction for maximum rigidity and reliable runout accuracy
PCD cutting edges for superior wear resistance in aluminum, magnesium, and composites
High concentricity control supporting stepped bore accuracy and repeatable geometry
Optional through-coolant for chip evacuation and thermal stability
Custom entry and lead geometry for controlled tool entry and reduced burr formation
Made-to-drawing customization for step distance, tolerance class, and surface finish targets

Benefits in Production

A 2-step PCD reamer with integrated shank provides measurable advantages:

Replaces multiple tools by combining two finishing operations into one
Reduces tool change time and improves CNC line uptime
Improves step-to-step positional consistency (coaxial accuracy)
Achieves tight tolerance performance (commonly IT6-class targets depending on setup)
Delivers high-quality surface finish (Ra ≤ 0.2 µm in suitable non-ferrous conditions)
Reduces tool deflection and vibration, improving dimensional repeatability
Lowers cost per component through longer tool life and reduced downtime

For production engineers, the main benefit is process stability: once the bore process window is established, size control and surface quality remain consistent across batches.

Engineering Notes for Best Results

To maximize reaming performance, the tool should be matched to the real machining system:

Pre-hole allowance: ensure correct pre-drilled or pre-bored diameter and straightness
Runout management: integrated shank helps, but spindle/holder condition still matters
Chip evacuation: through-coolant is recommended for deep bores or high throughput
Entry design: lead-in and chamfer geometry should match bore entrance requirements
Material condition: die-cast aluminum porosity and inclusions may influence edge prep choice
Coolant strategy: dry/MQL or coolant depending on part and machine condition

Aoshiji® can support drawing review to define lead geometry, land design, and flute specification based on the customer’s bore requirements and machine constraints.

Technical Specifications

Parameter	Specification
Tool Type	PCD Step Reamer (Integrated Shank)
Cutting Edges	6
Step Count	2 (Dual-Diameter Reaming)
Cutting Material	PCD (Polycrystalline Diamond)
Diameter Range	Ø6 – Ø25 mm (Customizable)
Shank Type	Solid Carbide or Steel Shank
Application Focus	Multi-diameter bore finishing in non-ferrous alloys
Coolant Supply	Through-coolant optional
Tolerance	Bore concentricity ≤ 5 µm (custom tighter available)
Customization	Made to drawing / made to bore requirement

Options & Customization

Aoshiji® Custom Tool provides full customization for stepped bore requirements:

Flute configurations: 2, 3, 4, or 6-flute designs
Geometry options: single-step, dual-step, or multi-step reamers
Through-coolant or solid designs depending on chip evacuation needs
Custom shank dimensions for HSK, BT, Weldon, or machine-specific holders
Tailored tolerance class and surface finish targets per drawing
Entry chamfer, lead angle, and step transition optimization
Edge preparation selection for material and porosity conditions

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Contact

For detailed bore drawings, technical consultation, or quotations, please contact:
[email protected]
Aoshiji® Custom Tool – Precision PCD and Custom CNC Tooling Solutions