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The narrow tip enters a prepared straight pilot hole.
Reamers / Tapered reamers
Tapered Reamers
What Is a Tapered Reamer and How Does It Work?
A tapered reamer is a finishing tool for creating conical holes that match tapered pins, fittings, and other angled components. It removes stock progressively along the taper to produce the specified mating profile.
Angled Cutting
Conical cutting edges progressively remove material from the hole wall as the tool advances.
Chip Evacuation
Straight or spiral flute valleys carry chips away from the cutting edges.
Final Sizing
The reamer finishes the cavity to the taper rate or custom profile required by the mating component.
Key Features and Benefits of Tapered Reamers
Standard and Custom Tapers
Can be produced for standard taper-pin profiles or specified custom angles.
Robust Flutes
Provide cutting-edge support for material removal on angled bore walls.
Square-Shank Options
Allow manual operation with a tap wrench.
Ground Cutting Edges
Support close taper control and internal surface finishing.
Small Size Availability
Includes small designations such as a 2/0 taper reamer for delicate mechanisms.
Rigid Core
Limits deflection and bending in deeper conical holes.
Tapered Reamer Specifications
| Specification | Range / Details |
|---|---|
| Taper Rate | 1/4" per foot standard, or custom profiles |
| Size Designations | #7/0 to #14, metric, and fractional |
| Flute Geometry | Straight, left-hand spiral, or right-hand spiral |
| Shank Type | Straight, square end, or Morse taper |
| Tolerance | Precision ground to OEM requirements |
| Operation Type | Tapered through-holes and blind holes |
Materials and Coatings Available for Tapered Reamers
| Material / Coating | Best For | Key Advantage |
|---|---|---|
| HSS (High-Speed Steel) | General machining on mild steel and aluminum. | Tough, economical substrate for manual and machine use. |
| Cobalt Steel (HSS-Co) | Harder alloys and abrasive cast irons. | Heat resistance and edge retention support demanding applications. |
| TiAlN Coating | High-temperature, higher-volume production. | Reduces friction and protects the cutting edge against heat and wear. |
HSS suits general manual and machine work, HSS-Co adds heat and wear resistance, and TiAlN can protect cutting edges in compatible higher-temperature processes.
Which Machines Use Tapered Reamers?
T-Handle Tap Wrenches
Turn square-shank tools manually for controlled taper finishing.
CNC Milling Centers
Use rigid holders for automated conical-hole finishing.
Manual Drill Presses
Provide vertical stability and controlled feed for repeatable taper generation.
Applications and Industries for Tapered Reamers
Pin Fastening
Creates conical cavities for taper pins used to locate and lock machine components.
Suspension Maintenance
Finishes steering-knuckle and ball-joint tapers for matching chassis parts.
Custom Tooling
Produces specified conical hole profiles in specialized jigs and fixtures.
Pipe and Valve Fittings
Finishes angled holes for specialized fluid-control valves and tapered connections.
Frequently Asked Questions About Tapered Reamers
What is the standard taper per foot for taper pin reamers?
Many industrial imperial taper pin reamers use a taper of 1/4 inch per foot. Confirm the reamer profile against the specified pin or mating component.
Can I use a tapered reamer in a hand drill?
Unsupported hand-drill use is generally not recommended because the tool can bind, chatter, or break. Use a rigid machine or turn a square-shank version slowly with a tap wrench.
What is a 2/0 taper reamer used for?
A 2/0, or two-aught, taper reamer finishes small taper-pin holes in delicate mechanisms, instruments, and small components.
Should I choose straight or spiral flutes?
Straight flutes suit continuous holes. Spiral flutes can bridge keyways and interrupted cuts with less tendency to grab.
Are custom taper angles available?
Custom tapered reamers can be specified by angle, taper rate, diameter, and length according to the part drawing.
Shared engineering resource
Design and Engineering Support
Bauron provides design and engineering support for standard and custom taper profiles, flute geometry, shank styles, substrates, and coatings. Share the mating-part drawing and application requirements for review.
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