Skip to content This AlCrN-coated 25 64 drill bit with coolant holes is designed for high-performance drilling in demanding machining environments. Manufactured from premium solid carbide and processed with advanced CNC grinding technology, the tool delivers excellent rigidity, precise diameter control, and superior wear resistance. The AlCrN coating provides outstanding heat resistance and oxidation stability, making this 25 64 drill bit ideal for high-speed and dry or semi-dry machining applications.
The internal coolant holes allow cutting fluid to reach the cutting edge directly, ensuring efficient chip evacuation, reduced cutting temperature, and extended tool life. This design significantly improves hole quality and dimensional consistency when drilling steel, stainless steel, alloy steel, cast iron, and other difficult-to-machine materials.
Available in standard 25 64 drill bit size, as well as 25 64 drill bit equivalent and 25 64 drill bit closest size options, this tool also supports 25 64 drill bit to mm and 25 64 drill bit conversion requirements. Custom flute length, overall length, and coating options are available upon request to match specific machining conditions.
3D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB310025 | 25/64 | 9.92 | 47 | 10 | 89 |
5D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB510025 | 25/64 | 9.92 | 61 | 10 | 103 |
Grade HN40 is made from submicron WC powder, some speclal additlves added to optimize theproperties with good combination of hardness and toughness.
Its suitable for making drills and miling tools for machining stainless steel, tool steel and heat-resistingalloys.
| Grade | Cobalt content % | Grain size | Density g/cm³ | Hardness HRA | Hardness HV30 | MPa Transverse rupture strength | MPa ·m1/2 Fracture toughness MPa ·m1/2 |
|---|---|---|---|---|---|---|---|
| HN40 | 10 | 0.8 | 14.45 | 91.8 | 1,580 | 3,600 | 11.8 |
| Scientific name | Composition | Physical properties | Features | Typical applications |
|---|---|---|---|---|
| ALCRN | Al: 18–32% Cr: 10–25% N: 45–57% | Hardness: 2800–3200 HV (≈30–32 GPa) Thickness: 1–5 μm (typically 3–4 μm in applications) Oxidation temperature: 1000–1100°C (short-term up to 1100°C) Deposition temperature: ＜500°C (suitable for HSS and carbide substrates) | Red hardness: maintains hardness even at 1100°C, better than TiAlN (whose hardness drops above about 900°C). Adhesion: critical load up to 40 N (with optimized process). Wear resistance: suitable for high-speed cutting and dry machining, especially effective on stainless steels and alloy steels. | Cutting tools: end mills, gear cutters, drills (e.g. Balinit Alcorna series). Moulds: aluminium die-casting moulds, stamping tools. Industrial parts: piston rings, high-temperature wear-resistant parts (combined with suitable interlayer design). |
Our 25 64 Drill Bit drawings clearly show key 25 64 Drill Bit dimensions such as diameter, radius, flute length and overall length. This helps you confirm the right 25 64 Drill Bit sizes for your CNC setup and machining depth before ordering.
A 25 64 drill bit size equals 25/64 inch, which is approximately 0.3906 inches in decimal form. It is a fractional inch drill size commonly used when standard sizes such as 3/8" or 13/32" do not meet dimensional requirements.
A 25 64 drill bit can be used for drilling:
Carbon steel
Stainless steel
Alloy steel
Cast iron
Aluminum
Copper and brass
Material suitability depends on whether the drill is HSS, cobalt, or carbide, and whether it has a coating.
Use correct speed and feed
Apply proper coolant or lubrication
Avoid excessive runout
Use rigid tool holders
Inspect cutting edges regularly
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
The AlCrN-coated 25 64 drill bit without coolant holes is designed for general-purpose and high-speed drilling where external coolant or air cooling is used. It delivers stable cutting performance, smooth chip evacuation, and reliable hole accuracy across a wide range of materials. The AlCrN coating forms a hard, heat-resistant surface layer that protects the cutting edges from premature wear, allowing this 25 64 drill bit to maintain sharpness even in continuous production.
Without internal coolant channels, the tool body remains more compact and rigid, making it suitable for applications that require higher strength and reduced risk of breakage. This design is commonly used in drilling steel, stainless steel, alloy steel, cast iron, aluminum, and other non-ferrous metals.
For users looking for a 25 64 drill bit equivalent, 25 64 drill bit alternative, or 25 64 drill bit closest size, inch and metric options including 25 64 drill bit to mm conversions are available. Multiple length types, cutting geometries, and coating variations can be selected to adapt to different machines and cutting conditions.
3D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB301025 | 25/64 | 9.92 | 47 | 10 | 89 |
5D
EDP No. | Fractional | Metric (D1, mm) | Flute Length L1 (mm) | Shank Diameter D2 (mm) | Overall Length L2 (mm) |
DB501025 | 25/64 | 9.92 | 61 | 10 | 103 |
Grade HN40 is made from submicron WC powder, some speclal additlves added to optimize theproperties with good combination of hardness and toughness.
Its suitable for making drills and miling tools for machining stainless steel, tool steel and heat-resistingalloys.
| Grade | Cobalt content % | Grain size | Density g/cm³ | Hardness HRA | Hardness HV30 | MPa Transverse rupture strength | MPa ·m1/2 Fracture toughness MPa ·m1/2 |
|---|---|---|---|---|---|---|---|
| HN40 | 10 | 0.8 | 14.45 | 91.8 | 1,580 | 3,600 | 11.8 |
| Scientific name | Composition | Physical properties | Features | Typical applications |
|---|---|---|---|---|
| ALCRN | Al: 18–32% Cr: 10–25% N: 45–57% | Hardness: 2800–3200 HV (≈30–32 GPa) Thickness: 1–5 μm (typically 3–4 μm in applications) Oxidation temperature: 1000–1100°C (short-term up to 1100°C) Deposition temperature: ＜500°C (suitable for HSS and carbide substrates) | Red hardness: maintains hardness even at 1100°C, better than TiAlN (whose hardness drops above about 900°C). Adhesion: critical load up to 40 N (with optimized process). Wear resistance: suitable for high-speed cutting and dry machining, especially effective on stainless steels and alloy steels. | Cutting tools: end mills, gear cutters, drills (e.g. Balinit Alcorna series). Moulds: aluminium die-casting moulds, stamping tools. Industrial parts: piston rings, high-temperature wear-resistant parts (combined with suitable interlayer design). |
Our 25 64 Drill Bit drawings clearly show key 25 64 Drill Bit dimensions such as diameter, radius, flute length and overall length. This helps you confirm the right 25 64 Drill Bit sizes for your CNC setup and machining depth before ordering.
A 25 64 drill bit size equals 25/64 inch, which is approximately 0.3906 inches in decimal form. It is a fractional inch drill size commonly used when standard sizes such as 3/8" or 13/32" do not meet dimensional requirements.
A 25 64 drill bit can be used for drilling:
Carbon steel
Stainless steel
Alloy steel
Cast iron
Aluminum
Copper and brass
Material suitability depends on whether the drill is HSS, cobalt, or carbide, and whether it has a coating.
Use correct speed and feed
Apply proper coolant or lubrication
Avoid excessive runout
Use rigid tool holders
Inspect cutting edges regularly
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
The 25 64 drill bit is widely used for precision drilling in automotive parts, machinery manufacturing, mold making, and general metalworking industries. It is suitable for producing accurate through-holes and blind holes in steel, stainless steel, aluminum, cast iron, and alloy materials.
For customers who need a 25 64 drill bit equivalent, 25 64 drill bit alternative, or are searching for the 25 64 drill bit closest size, we offer multiple inch and metric options to match different standards. Our drilling solutions support a variety of cutting conditions, helping users achieve stable performance and consistent hole quality across different machines and production environments.
Each 25 64 drill bit leads to reliable dimensional accuracy and repeatable performance through optimized flute geometry and precise CNC grinding. The cutting edges are designed to reduce cutting resistance and improve chip evacuation, resulting in smoother drilling and improved surface finish.
We also provide options for 25 64 drill bit size control, 25 64 drill bit to mm, and 25 64 drill bit conversion, ensuring compatibility with both imperial and metric systems. With selectable coatings, lengths, and geometries, our drills are engineered to deliver long tool life, stable performance, and cost-effective machining results.
We Are Commited To Providing High-Quality, Customized solutions At An Affordable price While Also Prioritizing sustainability And ExcellentCustomer Service, These Qualities Make Us A Great choice For Your 25 64 Drill Bit Needs
We Only Use unground tungsten carbide rods with HlP sintering and 100% virgin material. Our grade includes lsO K05 to K40, frommachining carbon steel to aluminium, non-ferrous metals andtitanium or we develop grade for your applications.
As a HNCarbide customer, you can enjoy five-axis high-precisiongrinding machines from Australia’s ANCA or Germany’s Walter. Themodern workshop with constant temperature and humidity ensuresthe accuracy of each 25 64 Drill Bit.
Each of your tungsten 25 64 Drill Bit will be sandblasted to effectively remove burrs and improve the finish.
All HNCarbide’s 25 64 Drill Bit will be monitored on WALTER HELICHEEK and ZOLLER GENlUS 3 to ensure that every dimension is qualified. We arecommitted to controlling the tolerance within 3 UM.
At HNCarbide, every shipment is meticulously packaged to ensure your tools arrive intact.
Each HNCarbide’s 25 64 Drill Bit is individually placed in a shock-resistant protective case, labeled with complete specifications, and sealed in moisture-proof packaging material before being boxed.
Large-volume orders are reinforced with double-wall cardboard boxes or wooden crates to maximize safety during international shipping.
We collaborate with reliable logistics partners to ensure goods are delivered quickly and securely to their destination via air freight, sea freight, or express courier.
A 25 64 drill bit size equals 25/64 inch, which is approximately 0.3906 inches in decimal form. It is a fractional inch drill size commonly used when standard sizes such as 3/8" or 13/32" do not meet dimensional requirements.
A 25 64 drill bit can be used for drilling:
Carbon steel
Stainless steel
Alloy steel
Cast iron
Aluminum
Copper and brass
Material suitability depends on whether the drill is HSS, cobalt, or carbide, and whether it has a coating.
Use correct speed and feed
Apply proper coolant or lubrication
Avoid excessive runout
Use rigid tool holders
Inspect cutting edges regularly
Yes. We can produce non-standard tools according to your drawings, samples or machining requirements (material, coating, size, tolerance and application). Our engineers will evaluate and provide a quotation and lead time.
For serious buyers and distributors, we can offer free standard samples if in stock. Usually you only need to cover the freight cost. For customized tools, a sample fee may apply, which can be refunded or deducted in bulk orders.
Yes.
Regional or customer protection based on sales targets, avoiding price wars among our partners.
Catalogs, brochures, product photos, technical data sheets, online materials.
For key partners, joint promotion, exhibitions and digital marketing support.
Safety stock for fast-moving items and forecast-based production.
Priority production and regular shipments to reduce stock-out risk.
Clear quality warranty policy, quick response to claims.
Replacement, credit or other solutions after confirmation of issues.
Tool selection and cutting parameter advice.
Problem analysis for different materials and machines.
Online training, documents, and when possible, on-site support for key accounts.
The 25 64 drill bit is a commonly used fractional inch drill size in precision machining, metalworking, and industrial manufacturing. Although it may not be as widely recognized as standard sizes like 1/4" or 3/8", this drill bit plays an important role when tighter dimensional accuracy is required. Understanding the 25 64 drill bit size, its metric conversion, closest alternatives, and suitable applications can help machinists select the right tool and achieve consistent drilling results.
In this guide, we will explain what a 25 64 drill bit is, how it compares to other sizes, and how to choose the best option for your machining needs.
A 25 64 drill bit refers to a fractional inch drill with a diameter of 25/64 inch. Fractional sizes are commonly used in North America and many industrial applications that still rely on inch-based tooling systems.
The decimal equivalent of a 25/64 drill bit is:
25 ÷ 64 = 0.3906 inches
This makes it slightly larger than 3/8 inch (0.375") and smaller than 13/32 inch (0.40625").
Because of this intermediate size, the 25 64 drill bit is often selected when standard sizes are either too small or too large for a specific tolerance requirement.
Many machinists work in mixed inch and metric environments, making conversion an important factor.
To convert inches to millimeters:
0.3906 inches × 25.4 = 9.92 mm (approx.)
So, the 25 64 drill bit to mm conversion is approximately 9.9 mm.
There is no exact metric equivalent, but 9.9 mm and 10 mm are the most commonly used metric references. When strict tolerances are required, selecting a 9.9 mm drill or using a reamer after drilling may be necessary.
Understanding how this size fits among neighboring drill sizes helps when choosing substitutes.
| Drill Size | Decimal (in) | Metric (mm) |
|---|---|---|
| 3/8" | 0.3750 | 9.53 |
| 25/64" | 0.3906 | 9.92 |
| 13/32" | 0.4063 | 10.32 |
| 9.9 mm | 0.3898 | 9.90 |
| 10 mm | 0.3937 | 10.00 |
This comparison shows why users often search for:
25 64 drill bit closest size
25 64 drill bit equivalent
25 64 drill bit alternative
No. Although they are close, a 25 64 drill bit is not the same as 3/8.
3/8" = 0.3750"
25/64" = 0.3906"
The difference of 0.0156 inches (0.4 mm) can be significant in precision applications. If hole size accuracy matters, these two sizes should not be used interchangeably.
A 25 64 drill bit is commonly used in:
Precision through-holes and blind holes
Pre-drilling before tapping
Clearance holes for specific fasteners
Automotive and machinery components
Mold and die manufacturing
General CNC machining
This size is especially useful when standard fractional or metric sizes cannot meet tolerance requirements.
Not all drill bits perform the same. Selecting the correct type depends on material, cutting conditions, and production volume.
Cost-effective
Suitable for mild steel, aluminum, plastics
Lower wear resistance
Better heat resistance than standard HSS
Suitable for stainless steel and harder alloys
High hardness and wear resistance
Ideal for CNC machining
Excellent for stainless steel, alloy steel, cast iron
Reduced friction
Improved tool life
Higher cutting speed capability
For demanding applications, a carbide 25 64 drill bit with coating offers the best performance and stability.
Some 25 64 drill bits are available with internal coolant holes, while others are solid.
With Coolant Holes
Direct coolant to cutting edge
Better chip evacuation
Lower cutting temperature
Ideal for deep holes and high-speed machining
Without Coolant Holes
Higher rigidity
Simpler structure
Suitable for external coolant or air blast
Your choice depends on hole depth, material, and machine capability.
When an exact 25/64 size is unavailable, conversion strategies include:
Use a 9.9 mm drill as a 25 64 drill bit equivalent
Drill slightly undersize, then ream to final dimension
Use a 25 64 drill bit closest size and adjust tolerances
For critical fits, always verify with test drilling and measurement.
What is equivalent to 25 64 drill bit?
Approximately 9.9 mm.
What is the next size up from 25 64 drill bit?
13/32" or 10 mm.
What is the next size down?
3/8" or 9.5 mm.
Is 25 64 drill bit available in metric sets?
Usually found in inch sets, but metric equivalents may be offered.
Many users search for:
25 64 drill bit Home Depot
25 64 drill bit Lowes
These retailers may carry limited selections. For industrial-grade carbide drills, better options include specialized tooling suppliers, manufacturers, and B2B distributors who can offer coatings, tolerances, and customization.
Use correct spindle speed and feed rate
Apply appropriate coolant or lubrication
Use rigid tool holders
Avoid excessive runout
Inspect cutting edges regularly
Proper setup significantly extends the life of your 25 64 drill bit and improves hole quality.
The 25 64 drill bit is an important fractional size for precision drilling where standard sizes are not sufficient. Understanding its exact size, metric conversion, closest alternatives, and tool material options allows machinists to make better tooling decisions.
Whether you need a standard HSS version or a high-performance carbide solution, selecting the right 25 64 drill bit size and configuration will help ensure accuracy, efficiency, and consistent machining performance.
Before you go, please note that we offer the most up-to-date industry research reports and the most comprehensive product catalogs, so please contact us if you are interested!
Before you go, please note that we offer the most up-to-date industry research reports and the most comprehensive product catalogs, so please contact us if you are interested!
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