Carbide-Tipped Drill Bits for Metal Machining
Aoshiji is a custom manufacturer of carbide-tipped drill bits and brazed carbide drills made to customer drawings for large-diameter, stepped, formed, combination and other non-standard metal hole-making applications.
Each drill uses carbide cutting elements brazed to an engineered steel body and is designed from the finished hole geometry, workpiece material and hardness, machining allowance, dimensional tolerance, required surface finish, machine interface, cutting conditions, coolant method, chip-evacuation requirements and target tool life.
Typical projects include bearing cages, hydraulic components, castings, automotive parts and heavy-equipment components where standard drills cannot efficiently produce the required geometry or where a large or complex full-carbide tool would require excessive carbide material.
Custom Carbide-Tipped Drill Bits at a Glance
| Item | Capability |
|---|---|
| Tool Construction | Brazed carbide tips, blades or profiled carbide segments on an engineered steel body |
| Drill Types | Large-diameter, step, form, combination, radius/ball-end, long-reach and internal-coolant drills |
| Manufacturing Basis | Customer part drawing, tool drawing or approved custom design |
| Hole Features | Multiple diameters, radii, chamfers, tapers, counterbored sections and special bottom profiles |
| Typical Materials | Cast iron, ductile iron, carbon/alloy steel, aluminum, brass, bronze and copper alloys |
| Coolant | Internal or external coolant where tool structure permits |
| Manufacturing Support | Engineering review, controlled brazing, precision grinding and drawing-based inspection |
| RFQ Basis | Drawing, material, hole geometry, tolerance, machine, coolant, cutting data and quantity |
Table of Contents
01 Custom Brazed Carbide Drills Overview
02 Custom Brazed Carbide Drills: Terminology and Construction
03 When Carbide-Tipped Drill Construction Makes Sense
04 Types of Custom Brazed Carbide Drills and Carbide-Tipped Drill Bits
05 Supported Hole Features and Profile Geometry
06 When to Use Custom Carbide-Tipped Drills
07 Applications and Workpiece Materials for Custom Brazed Carbide Drills
08 Engineering Design Options
09 Drill-Point Geometry, Edge Preparation, Chip Evacuation and Coolant
10 Machining Problems, Tool Life and Performance Targets
11 Tool Life, Regrinding and Production Economics
12 Technical Information Required for a Custom Drill Quotation
13 Aoshiji® Engineering, Manufacturing and Inspection Capabilities
14 Frequently Asked Questions
15 Related Products and Case Studies
01 Custom Brazed Carbide Drills Overview
Carbide-tipped drill bits combine high wear resistance at the carbide cutting edges with the toughness and structural support of a steel drill body.
The carbide is positioned only at the cutting areas, while the steel body provides structural support, toughness and greater flexibility for large diameters, long reaches, multiple steps and special hole profiles.
Typical applications include:
- Large-diameter drilling
- Step-hole machining
- Formed-hole machining
- Combined drilling and chamfering
- Combined drilling and counterboring
- Radius-profile hole machining
- Tapered-hole preparation
- Long-reach drilling
- Casting machining
- Drawing-based special hole-making
Carbide-tipped construction can be practical when manufacturing the entire drill from solid carbide would require excessive carbide material or when a tough steel body is required.
However, the construction should not be selected according to diameter alone.
Important engineering inputs include:
- Finished hole geometry
- Workpiece material and hardness
- Hole depth
- Entry and exit conditions
- Continuous or interrupted cutting
- Machining allowance
- Required hole tolerance
- Required surface finish
- Machine rigidity
- Tool-holder interface
- Cutting speed and feed
- Coolant delivery
- Chip evacuation
- Target tool life
- Regrinding requirements
For a broader explanation of carbide-tipped and brazed carbide tool construction, see our main guide: Custom Carbide-Tipped Cutting Tools.When a standard drill cannot meet a non-standard diameter, stepped profile, flat-bottom feature, dimensional tolerance, surface-finish requirement or cycle-time target, a custom brazed carbide drill can be engineered around the part drawing and actual machining conditions.
02 Custom Brazed Carbide Drills: Terminology and Construction
Brazed Construction of Custom Brazed Carbide Drills
In industrial metal machining, the terms carbide-tipped drill bit and brazed carbide drill commonly describe the same basic construction: carbide cutting elements permanently brazed to a steel drill body.
Custom brazed carbide drills are manufactured using a controlled brazing process to create a stable bond between the carbide cutting elements and the engineered steel body.
Where the design requires additional edge support or regrinding allowance, brazed drills can use relatively thick carbide cutting elements while retaining a tough steel support structure.
The terms emphasize different aspects of the tool.
| Term | Meaning |
|---|---|
| Carbide-tipped drill bit | Emphasizes that the cutting edges or cutting elements are made from carbide |
| Carbide-tipped drill | Professional engineering description of the same drill construction |
| Brazed carbide drill bit | Emphasizes that brazing joins the carbide cutting elements to the steel body |
| Brazed carbide drill | Common industrial term for a steel-bodied drill with brazed carbide cutting edges |
| Custom carbide-tipped drill | Drawing-specific carbide-tipped or brazed-carbide construction developed for a non-standard hole geometry or machining condition |
| Custom form drill | A cutting drill whose edge profile generates a defined hole form |
On this page, these terms refer specifically to custom drills using carbide tips, blades, bars or profiled carbide segments brazed to steel bodies.
Typical applications include:
- Large-diameter holes
- Stepped holes
- Formed holes
- Radius transitions
- Chamfered entrances
- Combined drilling and counterboring
- Multiple connected hole features
- Special metal-machining applications
The terms do not indicate one universal carbide grade, drill-point geometry, steel-body material or brazing process. These must be selected according to the actual application.
Standard drilling tools are generally manufactured around established ISO, DIN, ANSI or manufacturer-standard dimensions, while custom brazed carbide drills are engineered around specific part drawings, hole geometries and machining requirements.
On this page, form drill means a cutting drill whose edges generate a defined hole profile. It does not refer to thermal friction drilling. On this page, custom drill refers specifically to carbide-tipped or brazed-carbide drill construction unless another tool structure is explicitly discussed for comparison.
03 When Carbide-Tipped Drill Construction Makes Sense
Carbide-tipped drill construction is especially practical for large-diameter, long-reach, stepped, formed and combination holes where a tough steel body provides structural support and carbide is required primarily at the cutting areas.
It is not automatically the best construction for every drilling operation. Smaller high-speed precision holes or standardized high-volume drilling may require a different tool structure. The final choice should be based on hole geometry, material, machine capability, production volume and total cost per finished hole.
Solid carbide drills may be preferable for smaller, standardized high-speed precision holes where full-carbide rigidity and cutting-edge geometry are more important than the structural flexibility of a steel-bodied brazed design.
For a detailed engineering comparison, see ：
Compare brazed carbide, solid carbide and indexable tools by rigidity, profile flexibility, tool life, cost and production volume.
Compared with solid carbide construction, a carbide-tipped drill uses carbide primarily at the cutting elements while the main tool body is made from lower-cost tool steel. For large-diameter or complex custom drills, this construction can reduce carbide material cost while retaining the toughness and structural support of a steel body.
04 Types of Custom Brazed Carbide Drills and Carbide-Tipped Drill Bits
Large-Diameter Carbide-Tipped Drills
Large-diameter carbide-tipped drills are designed for holes where solid-carbide construction would require a substantial amount of carbide material.
Typical applications include:
- Large cast components
- Bearing components
- Hydraulic components
- Gear housings
- Machinery parts
- Heavy-equipment components
- Large formed holes
The design must consider spindle power, torque, thrust force, machine rigidity, body strength, chip space and coolant delivery.
Carbide-Tipped Step Drills
Custom step drills machine two or more diameters in one operation.
By combining two or more diameters in one tool, custom carbide-tipped step drills can reduce drill changes and help shorten cycle time.
They may include:
- Two-step holes
- Multiple-step holes
- Pilot and main diameters
- Step-and-chamfer features
- Step-and-radius transitions
- Drilling and spotfacing features
Each cutting step should have sufficient chip space, cutting-edge support and clearance.
Carbide-Tipped Form Drills
Form drills generate a defined hole profile directly with the cutting-edge geometry.
Supported forms may include:
- Tapered sections
- Internal radii
- Entrance radii
- Ball-end profiles
- Concave transitions
- Convex transitions
- Angular profiles
- Multiple connected diameters
- Non-standard hole entrances
- Special bottom profiles
The cutting-edge profile may require compensation according to tool orientation, rake angle, clearance, cutting position and regrinding allowance.
Drill and Counterbore Combination Tools
Custom brazed carbide drills can combine drilling, counterboring, chamfering, stepped diameters or other connected hole features into one pass, reducing tool changes and cycle time.
Typical configurations include:
- Pilot drill and flat-bottom counterbore
- Drill and stepped counterbore
- Drill and form counterbore
- Drill, counterbore and chamfer
- Multiple-diameter combination tools
A counterbore performs a different cutting function from a conventional drill, but both features may be integrated into one custom tool.
Drill and Chamfer Combination Tools
These tools produce the hole and entrance chamfer in one operation.
They may help maintain the positional relationship between the hole and chamfer while reducing tool changes.When the geometry permits, custom brazed carbide drills can combine drilling, stepped diameters, counterboring and chamfering in one pass, helping reduce tool changes and cycle time.
Chamfer angle, cutting-edge overlap and burr control should be engineered according to the application.
Radius and Ball-End Form Drills
Radius-profile drills may be designed for:
- Spherical hole bottoms
- Ball-end features
- Rounded entrances
- Internal radius transitions
- Combined radius and chamfer features
Cutting forces and chip evacuation can vary across the curved cutting profile and must be evaluated carefully.
Long-Reach Carbide-Tipped Drills
Long-reach drills are used when the cutting section must reach a recessed or deep position.
Important considerations include:
- Tool overhang
- Body stiffness
- Runout
- Vibration tendency
- Chip evacuation
- Coolant access
- Machine and holder rigidity
A long-reach tool is not automatically a dedicated deep-hole drill. Deep-hole applications require separate review according to depth-to-diameter ratio and chip-removal method.
Internal-Coolant Carbide-Tipped Drills
Internal coolant passages may be incorporated when the tool-body diameter, wall thickness, carbide-seat design and holder interface permit a safe structure.
Coolant-hole position must not weaken the body or interfere with the brazed joint.
05 Supported Hole Features and Profile Geometry
Custom carbide-tipped drills can be designed around a wide range of hole and entrance features.
Typical features include:
- Straight holes
- Large-diameter holes
- Stepped holes
- Tapered sections
- Formed hole entrances
- Flat-bottom sections
- Radius transitions
- Internal chamfers
- External entrance chamfers
- Spherical bottoms
- Concave profiles
- Convex profiles
- Pilot diameters
- Counterbored sections
- Spotfaced sections
- Multiple connected diameters
- Combined drilling features
For complex form drilling, the drill cutting-edge profile may not be identical to the finished hole outline.
Profile compensation may be required according to:
- Drill orientation
- Rake angle
- Clearance angle
- Cutting direction
- Cutting diameter
- Workpiece entry geometry
- Regrinding allowance
- Required finished profile
The final cutting-edge geometry must remain manufacturable, grindable and inspectable.
Large profile widths or multiple cutting steps can generate high thrust and torque. The design should therefore be reviewed against:
- Machine rigidity
- Spindle power
- Holder strength
- Workpiece clamping
- Tool overhang
- Width of engagement
- Cutting allowance
- Required feed rate
06 When to Use Custom Carbide-Tipped Drills
Custom carbide-tipped drills are commonly considered when standard drills cannot meet the required geometry, hole stability, tool life or cost-per-hole target.
Typical conditions include:
- The hole diameter is outside the standard drill range
- Several diameters must be machined in one operation
- A standard drill cannot reproduce the required profile
- The hole requires a radius, taper, chamfer or special bottom form
- Multiple tools create witness marks between connected features
- Positional relationships between features are difficult to maintain
- Hole diameter is unstable
- Hole roundness is inconsistent
- Surface finish does not meet the requirement
- Chip packing occurs
- Cutting edges chip prematurely
- Tool life is inconsistent
- Tool changes increase cycle time
- A full-body carbide design would require excessive carbide material
- A long or heavy steel body is required
- The customer requires a made-to-drawing drilling tool
The final drill construction should be selected from the complete application—including hole geometry, material, machine capability, cutting conditions, production volume and cost-per-hole target—rather than from drill diameter alone.
Proven Carbide-Tipped Form Drill Application — Brass Bearing Cage
For a brass bearing cage application, Aoshiji developed a custom carbide-tipped form drill bit to machine a Ø60.8 mm spherical ball pocket with an R30.4 profile, a 2 mm × 45° entrance chamfer and an Ra 0.8–1.6 µm surface-finish requirement.
The drawing-specific drill used brazed carbide cutting elements on an engineered steel body and combined direct centering, spherical pocket generation and entrance chamfering in one tool. The production requirement also included light, easily removable burrs and a pocket wall without unacceptable scratches.
The final tool eliminated the separate spotting operation and separate chamfering tool while maintaining the required ball-pocket geometry and surface quality.
07 Applications and Workpiece Materials for Custom Brazed Carbide Drills
Carbide-tipped drills can be engineered for cast iron, ductile iron, hardened steel and non-ferrous materials by selecting the appropriate carbide grade, drill-point geometry, edge preparation, flute and chip-control geometry, coolant strategy and steel-body construction.Carbide tips provide high-temperature stability and strong wear resistance in abrasive materials, but the carbide grade, edge preparation and cutting geometry must be matched to the actual workpiece and machining conditions.
| ISO Group | Typical Materials | Typical Design Considerations |
|---|---|---|
| P | Carbon steel and alloy steel | Chip formation, cutting temperature, built-up edge and edge strength |
| M | Stainless steel | Work hardening, heat generation, positive geometry and coolant delivery |
| K | Gray cast iron and ductile iron | Abrasive wear, interrupted cutting, edge security and body support |
| N | Aluminum, brass, bronze and copper alloys | Sharp edges, polished rake surfaces, burr control and reduced adhesion |
| S | Heat-resistant alloys and titanium alloys | Heat resistance, cutting speed, edge security and tool suitability |
| H | Hardened steels and hardened materials | Hardness, cutting force, edge security and alternative cutting materials |
These ISO groups are application categories, not universal proprietary carbide-grade names.
Cast Iron and Ductile Iron
Typical applications include:
- Bearing cages and retainers
- Pump housings
- Valve bodies
- Gear housings
- Machine bases
- Large casting components
- QT400 ductile-iron components
- QT500 ductile-iron components
These applications may require:
- Tougher carbide direction
- Reinforced cutting edges
- Controlled edge rounding
- Strong carbide support
- Stable body construction
- Geometry suitable for abrasive or interrupted cutting
Carbon and Alloy Steel
Typical applications include:
- Shafts
- Flanges
- Machine components
- Automotive parts
- Welded structures
- General engineering parts
The drill design should consider:
- Chip formation
- Cutting temperature
- Cutting continuity
- Built-up edge
- Machining allowance
- Machine rigidity
- Coolant delivery
Stainless Steel
Stainless steel can produce high cutting temperatures, work hardening and difficult chip formation.
The drill may require:
- Positive cutting geometry
- Sufficient edge toughness
- Controlled edge preparation
- Effective coolant delivery
- Suitable flute and chip-control geometry
- Reduced tool overhang
Aluminum and Non-Ferrous Metals
Typical materials include:
- Aluminum alloys
- Brass
- Bronze
- Copper
- Copper alloys
- Other non-ferrous metals
These applications often benefit from:
- Sharp-ground cutting edges
- Polished rake surfaces
- Positive geometry
- Reduced edge rounding
- Burr-control geometry
- Reduced built-up edge and smearing
Heat-Resistant and Hardened Materials
Heat-resistant alloys, titanium alloys and hardened steels require application-specific review. Carbide-tipped drills can be engineered for heat-resistant alloys and other difficult-to-machine materials when the carbide grade, point geometry, edge preparation, coolant delivery and machine stability are matched to the actual cutting conditions.Whether carbide-tipped drill construction is appropriate depends on workpiece hardness, hole geometry, cutting load, machine rigidity, coolant delivery, required tool life and production volume.
08 Engineering Design Options
A custom carbide-tipped drill should be designed around the complete hole-making process rather than only the drill diameter.
Carbide Cutting-Element Configuration
The drill may use:
- Individual carbide tips
- Full-width carbide blades
- Long carbide bars
- Profiled carbide segments
- Multiple brazed cutting elements
- Continuous carbide cutting sections
The configuration depends on:
- Drill diameter
- Cutting load
- Point geometry
- Number of steps
- Available brazing area
- Cutting-force direction
- Required regrinding allowance
- Profile complexity
Carbide Grade Selection for Tool Life and Wear Resistance
Carbide-grade selection should balance:
- Wear resistance
- Fracture resistance
- Edge security
- Surface-finish requirements
- Cutting speed
- Feed rate
- Interrupted or continuous cutting
- Workpiece hardness
- Brazing compatibility
- Thermal behavior
The hardest carbide grade is not automatically the most suitable grade.
A harder grade may resist wear but chip under unstable or interrupted cutting. A tougher grade may provide better edge security but lower wear resistance.For abrasive or hard materials, custom drill geometry can be optimized by adjusting the carbide grade, rake angle, relief angle, point geometry and edge preparation to balance wear resistance, cutting force and edge security.
Drill Body and Core Design
The steel body should be selected according to:
- Drill diameter
- Overall length
- Cutting load
- Torque
- Thrust force
- Core thickness
- Tool overhang
- Holder interface
- Required strength
- Required toughness
- Heat-treatment requirements
- Brazing compatibility
- Dimensional stability
Typical body-material directions may include medium-carbon steel, 40Cr-type alloy steel, 42CrMo-type alloy steel, 4140-type alloy steel or other application-specific steels.
Carbide Seat and Brazed-Joint Design
The carbide seat must support the cutting element and provide a controlled brazing interface.
Important factors include:
- Contact-surface geometry
- Carbide support behind the cutting edge
- Cutting-force direction
- Joint clearance
- Brazing filler flow
- Thermal expansion difference
- Residual stress
- Cutting-load distribution
- Carbide thickness
- Regrinding allowance
A brazing gap that is too small may restrict filler flow. A gap that is too large may reduce joint stability.
The correct joint design depends on carbide size, steel-body material, tool geometry and brazing process.
Shank and Machine Interface
Custom carbide-tipped drills may use:
- Straight cylindrical shanks
- Weldon-flat shanks
- Morse taper shanks
- BT-related interfaces
- CAT-related interfaces
- HSK-related interfaces
- Flange-mounted bodies
- Threaded connections
- Integrated tool-holder structures
- Custom mounting systems
The interface must match the machine, torque requirement, drill diameter, tool length and required runout.
Dynamic Balancing
Large or high-speed rotating drills may require dynamic balancing.
The required balance level depends on:
- Tool diameter
- Tool mass
- Mass distribution
- Operating speed
- Holder interface
- Machine condition
Dynamic balancing should be specified only where required by the actual application.
09 Drill-Point Geometry, Edge Preparation, Chip Evacuation and Coolant
Drill-Point Geometry
Engineering review may include:
- Point angle
- Chisel-edge geometry
- Lip height
- Cutting-lip symmetry
- Web thickness
- Web thinning
- Pilot geometry
- Step overlap
- Rake angle
- Clearance angle
- Margin or guide section
- Body clearance
- Corner radius
- Chamfer geometry
The point geometry must balance penetration, thrust force, cutting-edge strength, centering and chip formation.
Cutting-Edge Preparation
Available cutting-edge conditions may include:
- Sharp-ground edge
- Small cutting-edge chamfer
- Micro-radius edge
- Edge honing
- Controlled edge rounding
- Reinforced edge preparation
- Polished rake surface
Stronger edge preparation may be suitable for:
- Cast iron
- Ductile iron
- Interrupted entry
- Heavy machining allowance
- Abrasive materials
- Unstable machine conditions
Sharper edges may be suitable for:
- Aluminum
- Brass
- Bronze
- Copper alloys
- Burr-sensitive components
- Applications requiring low cutting forces
Excessive edge rounding can increase thrust force and reduce profile accuracy. Edge preparation should therefore be controlled rather than universally applied.
Flute and Chip-Space Design
Flute geometry influences:
- Chip volume
- Chip direction
- Core strength
- Cutting-edge support
- Coolant access
- Drilling depth
- Feed capability
Insufficient chip space can cause chip packing, increased torque, thermal damage and cutting-edge failure.
Chip-Control Geometry
Chip-control features should be selected according to:
- Workpiece material
- Cutting allowance
- Feed rate
- Hole depth
- Chip thickness
- Number of cutting steps
- Cutting direction
- Coolant method
- Required surface finish
Chipbreaker width, depth, position and profile should control chip flow without unnecessarily weakening the cutting edge.
Coolant Delivery
Available coolant strategies may include:
- External coolant
- Internal coolant
- Air-assisted chip evacuation
- Oil-based coolant
- Water-soluble emulsion
Internal coolant can help deliver coolant to the cutting zone and support chip evacuation, particularly in long or stepped holes.
Coolant passages must not weaken the drill body or interfere with the brazed joints.
10 Machining Problems, Tool Life and Performance Targets
Custom drilling tools are particularly useful where tight tolerances, complex hole geometries, dimensional accuracy, surface finish or tool life cannot be maintained reliably with standard drills. Machine and toolholder stability are essential to control vibration and achieve consistent machining results.With the correct carbide grade, cutting geometry and machining parameters, carbide drills can maintain cutting-edge performance under elevated cutting temperatures while supporting stable surface finish and tool life in demanding production.
Custom carbide-tipped drills are generally developed to solve a specific production problem rather than only to meet a nominal diameter.
Common problems include:
- Standard drills cannot generate the required hole profile
- Several drills create witness marks between steps
- Hole diameter is unstable
- Hole roundness is inconsistent
- Step positions vary
- Radius or chamfer dimensions are inaccurate
- Surface finish does not meet the requirement
- Drill wandering affects positional accuracy
- Chatter or vibration marks occur
- Cutting edges chip prematurely
- Tool life is inconsistent
- Chip packing occurs
- Coolant does not reach the cutting zone
- Burr formation is difficult to control
- Multiple tools increase cycle time
- Solid-carbide construction is uneconomical
- Standard indexable inserts cannot reproduce the required geometry
The custom drill should be evaluated against measurable targets such as:
- Hole diameter tolerance
- Hole roundness
- Cylindricity
- Step-position tolerance
- Angle tolerance
- Radius accuracy
- Chamfer dimensions
- Hole depth
- Surface finish
- Cycle time
- Cutting-edge condition
- Chip evacuation
- Tool life
- Regrinding potential
- Cost per finished hole
A custom drill should not be evaluated only by its purchase price.
The complete comparison should include:
- Machining time
- Tool life
- Setup time
- Tool changes
- Inspection time
- Scrap risk
- Regrinding cost
- Cost per component
- Cost per finished hole
11 Tool Life, Regrinding and Production Economics
Production volume affects the economic justification for custom tooling. Tool selection should therefore consider cost per finished hole, cycle time, tool-change frequency, regrinding potential, reject rate and expected production quantity rather than purchase price alone.
Custom carbide-tipped drills can be manufactured for prototype and small-batch requirements as well as repeat production, with the tool design, carbide configuration and regrinding strategy matched to the expected production run.
Carbide-tipped construction can be economical when:
- The drill has a large diameter
- The tool body is long or heavy
- The hole profile is non-standard
- Only the cutting edges require carbide performance
- Several hole features can be combined into one tool
- A full-carbide body would require excessive carbide material
- Production volume does not justify a complex replaceable-edge holder
- A tough steel body is required
- The drill can be reground
- The steel body may be reused through retipping
Potential lifecycle options include:
- Cutting-edge regrinding
- Profile regrinding
- Step-diameter restoration
- Margin or guide-section correction
- Retipping when structurally feasible
- Reuse of the steel body
Regrinding and retipping feasibility must be evaluated according to:
- Remaining carbide thickness
- Profile tolerance
- Drill-point geometry
- Brazed-joint condition
- Body condition
- Runout
- Original design allowance
Carbide-tipped construction is not automatically less expensive in every case. The correct comparison is total cost per finished hole.
12 Technical Information Required for a Custom Drill Quotation
To evaluate and quote a custom carbide-tipped drill, please provide as much of the following information as possible:
Exact specifications should define the finished hole geometry, dimensional tolerances, surface-finish requirement and expected production run so that the drill can be engineered for both machining performance and lifecycle cost.
- Part drawing
- Existing drill drawing
- Workpiece material
- Workpiece hardness
- Hole diameter
- Hole depth
- Step diameters
- Step lengths
- Radius dimensions
- Chamfer dimensions
- Taper dimensions
- Bottom-hole geometry
- Dimensional tolerance
- Required surface finish
- Through-hole or blind-hole application
- Existing hole or solid-material drilling
- Machine-tool type
- Spindle or tool-holder interface
- Cutting direction
- Tool overhang
- Machining allowance
- Coolant method and pressure
- Existing cutting speed and feed
- Current tool life
- Current machining problem
- Required quantity
- Target cycle time
- Target tool life
- Regrinding or retipping requirements
For replacement-tool projects, customers may also provide:
- Existing tool photographs
- Worn tool samples
- Failure photographs
- Previous cutting data
- Inspection reports
- Workpiece photographs
- Photographs of chips
- Machine and holder information
A complete part drawing is especially important when the cutting-edge profile must be calculated from the finished hole geometry.
Send drawings and technical information to:
13 Aoshiji® Engineering, Manufacturing and Inspection Capabilities
Aoshiji® Custom Tool provides engineering review, manufacturing, controlled brazing, precision grinding and inspection for drawing-based custom drilling projects.
Learn more about our brazed carbide tool manufacturing process and inspection and quality control for drawing-specific cutting tools.
Technical Information and Engineering Review
Engineering review may include:
- Part and drill drawing review
- Workpiece-material analysis
- Hole-profile calculation
- Cutting-force direction
- Torque and thrust evaluation
- Drill-body strength
- Core-thickness evaluation
- Carbide support structure
- Drill-point geometry
- Flute and chip-space design
- Coolant requirements
- Holder and machine compatibility
- Regrinding allowance
- Inspection criteria
Manufacturing
Depending on the drill design, manufacturing may include:
- Steel-body machining
- Tool-body heat treatment
- Carbide cutting and preparation
- Carbide-seat fitting
- Controlled brazing
- Precision drill-point grinding
- Step and profile grinding
- Flute grinding
- Clearance grinding
- Chipbreaker grinding
- Cutting-edge honing
- Controlled edge rounding
- Cutting-edge chamfering
- Shank and locating-surface grinding
- Internal coolant-hole manufacturing where structurally feasible
- Dynamic balancing where required
- Surface treatment
- Tool marking
Inspection
Final inspection is defined according to the customer drawing and functional requirements of the drill.
Inspection may include:
- Overall dimensions
- Drill diameter
- Step diameters
- Step lengths
- Point angle
- Cutting-lip symmetry
- Lip height variation
- Radius dimensions
- Chamfer dimensions
- Taper dimensions
- Shank dimensions
- Locating surfaces
- Radial runout
- Axial runout where applicable
- Concentricity
- Cutting-edge condition
- Brazed-joint condition
- Coolant-hole condition
- Drawing compliance
The inspection method and acceptance criteria are determined according to the customer drawing, exact specifications, drill function and required finished-hole geometry.
14 Frequently Asked Questions
Are carbide-tipped drill bits and brazed carbide drills the same?
In many metal-machining applications, both terms describe a steel-bodied drill with carbide cutting elements permanently brazed to the cutting area. Carbide-tipped emphasizes the cutting material, while brazed carbide emphasizes the joining process.
Are carbide-tipped drills the same as solid-carbide drills?
No. A carbide-tipped drill uses carbide only at the cutting areas and has a steel body. A solid-carbide drill is manufactured mainly or entirely from carbide.
When should I use a carbide-tipped drill bit?
It may be suitable for large diameters, long bodies, stepped holes, formed holes, combined features and low-to-medium-volume custom applications where solid carbide would require excessive material cost.
Can a custom carbide-tipped drill machine several diameters, radii or chamfers in one operation?
Yes. Custom step drills can combine multiple diameters, chamfers, radii or counterbored features when the tool structure and chip space permit.
Can internal coolant be added?
Internal coolant may be incorporated when the body diameter, wall thickness, carbide-seat design and machine interface permit a safe structure.
Can carbide-tipped drills be reground or retipped?
Many carbide-tipped drill designs can be reground when sufficient carbide allowance remains. Some larger drills may also be retipped when the steel body and brazed-seat structure remain dimensionally sound. Feasibility depends on the cutting profile, remaining carbide thickness, tolerance, joint condition and original tool design.
Which materials are suitable for carbide-tipped drill bits?
Typical materials include cast iron, ductile iron, carbon steel, alloy steel, stainless steel, aluminum, brass, bronze and copper alloys. The carbide grade and geometry must be selected for the actual material and cutting conditions.
How do I specify a custom carbide-tipped drill?
Provide the part or drill drawing, workpiece material and hardness, hole geometry, dimensional tolerance, surface finish, machine and holder information, coolant method, existing cutting conditions, current machining problem, required quantity and target tool life.
15 Related Carbide-Tipped Tool Pages
Flat-bottom, stepped, guided and profile counterbores for precision recess machining.
Made-to-drawing form tools for profiles, radii, steps, tapers, grooves and combined features.
Step, taper, form and internal-coolant reamers designed for precision hole finishing.
Overview of custom carbide-tipped cutting tools for turning, drilling, reaming, milling, counterboring and profile machining.
16 Conclusion
Custom carbide-tipped drills are engineered hole-making tools with carbide cutting edges brazed onto steel tool bodies. They are also known as brazed carbide drills or custom brazed carbide drilling tools.
They are especially useful for large-diameter holes, step holes, formed holes, long-reach drilling, special hole-making profiles, and custom metal machining applications where standard drills cannot meet the required geometry, stability, tool life, or cost target.
For many large, long, or non-standard drilling applications, carbide-tipped construction provides a practical balance between carbide cutting performance, steel body toughness, tool cost, and production stability.
If you need a custom carbide-tipped drill based on your drawing, workpiece material, hole requirement, and machining condition, Aoshiji® Custom Tool can provide practical engineering support and custom tooling recommendations.
Submit Your Custom Drill Project
Send your part drawing, existing drill drawing, workpiece material and machining information to [email protected] for engineering review and quotation.
Aoshiji® will evaluate the drill construction, carbide configuration, point and profile geometry, steel-body design, brazed-joint requirements, chip evacuation, coolant delivery, holder compatibility and inspection criteria before preparing the quotation.
