Hole-Making Tools
HRC55 Golden Coated Solid Carbide Center Spot Drill
2-Flute 90° Spotting Drill for Steel and Cast Iron
PENGFU HRC55 solid carbide center spot drills are designed for accurate hole positioning, spot drilling and chamfering in steel, alloy steel, mold steel and cast iron.
The rigid two-flute geometry and precision-ground 90° point help prevent drill wandering and produce an accurate starting position for subsequent drilling operations. A golden wear-resistant coating improves heat resistance, reduces friction and helps extend tool life during high-speed machining.
Product Features
90° Precision Point
The accurately ground 90° point provides reliable positioning and is suitable for spot drilling, countersinking and 45° edge chamfering.
Two-Flute Cutting Geometry
The two-flute design provides balanced cutting forces, stable chip evacuation and good tool rigidity.
Accurate Hole Positioning
The short, rigid cutting section minimizes tool deflection and helps prevent the following drill from wandering.
Golden Wear-Resistant Coating
The golden coating improves resistance to heat, oxidation and abrasive wear when machining steel and cast iron.
Fine-Grain Solid Carbide
Manufactured from fine-grain solid carbide for high hardness, dimensional stability and consistent cutting-edge performance.
Precision-Ground Cutting Edges
Precision grinding helps maintain point accuracy, diameter consistency and reliable machining results.
Suitable for Workpieces up to HRC55
Recommended for general and semi-hardened steel, mold steel and cast iron with workpiece hardness up to approximately HRC55.
Product Information
| Item | Description |
|---|---|
| Product Name | HRC55 Golden Coated Solid Carbide Center Spot Drill |
| Tool Material | Fine-Grain Solid Carbide |
| Number of Flutes | 2 Flutes |
| Point Angle | 90° |
| Coating | Golden Wear-Resistant Coating |
| Cutting Direction | Right-Hand Cutting |
| Shank Type | Straight Shank |
| Manufacturing Method | Precision Ground |
| Recommended Hardness | Workpiece hardness up to approximately HRC55 |
| Main Applications | Spot Drilling, Positioning and Chamfering |
Recommended Workpiece Materials
- Carbon steel
- Alloy steel
- Tool steel
- Mold steel
- Pre-hardened steel
- Stainless steel under stable cutting conditions
- Gray cast iron
- Ductile cast iron
Reference Specifications
Unit: mm
| Cutter Dia. D | Point Angle | Shank Dia. D2 | Overall Length L2 |
|---|---|---|---|
| 1.0 | 90° | 4 | 50 |
| 2.5 | 90° | 4 | 50 |
| 3.0 | 90° | 3 | 50 |
| 3.0 | 90° | 4 | 50 |
| 4.0 | 90° | 4 | 50 |
| 5.0 | 90° | 5 | 50 |
| 6.0 | 90° | 6 | 50 |
| 8.0 | 90° | 8 | 60 |
| 10.0 | 90° | 10 | 75 |
| 12.0 | 90° | 12 | 75 |
| 4.0 | 90° | 4 | 100 |
| 6.0 | 90° | 6 | 100 |
| 8.0 | 90° | 8 | 100 |
| 10.0 | 90° | 10 | 100 |
| 12.0 | 90° | 12 | 100 |
| 16.0 | 90° | 16 | 100 |
The specifications above are provided for selection reference only. Actual stock dimensions, coating type and dimensional tolerances should be confirmed before ordering.
Dimension Description
- D: Cutter diameter
- D2: Shank diameter
- L2: Overall length
- A: Point angle—90°
- Z: Number of flutes—2 flutes
Reference Dimensional Tolerance
| Cutter Diameter | Diameter Tolerance |
|---|---|
| D ≤ 12 mm | 0 / −0.015 mm |
| D > 12 mm | 0 / −0.020 mm |
Special tolerances can be supplied according to customer drawings and machining requirements.
Reference Cutting Conditions
| Workpiece Material | Material Condition | Recommended Vc |
|---|---|---|
| Carbon steel | Below HRC30 | 40–70 m/min |
| Alloy steel | HRC30–40 | 35–60 m/min |
| Tool or mold steel | HRC40–50 | 25–45 m/min |
| Hardened mold steel | HRC50–55 | 15–30 m/min |
| Gray cast iron | Below HRC32 | 60–120 m/min |
| High-alloy cast iron | HRC35–45 | 40–80 m/min |
Actual cutting conditions should be adjusted according to machine rigidity, tool diameter, tool overhang, workpiece hardness, coolant conditions and required hole accuracy.
Reference Machining Parameters
The following values are starting recommendations for spot drilling carbon steel below approximately HRC30.
| Cutter Dia. | Spindle Speed | Feed Rate |
|---|---|---|
| 3 mm | 4,000–7,000 rpm | 80–180 mm/min |
| 4 mm | 3,000–5,500 rpm | 100–220 mm/min |
| 6 mm | 2,000–3,700 rpm | 120–260 mm/min |
| 8 mm | 1,500–2,800 rpm | 130–300 mm/min |
| 10 mm | 1,200–2,200 rpm | 140–320 mm/min |
| 12 mm | 1,000–1,900 rpm | 140–320 mm/min |
| 16 mm | 750–1,400 rpm | 120–280 mm/min |
Use the parameters above only as initial settings. Conduct a machining test before batch production.
Recommended Machining Method
- Keep tool overhang as short as possible.
- Use a rigid tool holder with low runout.
- Align the tool accurately with the spindle centerline.
- Apply air blast or coolant to remove chips.
- Avoid excessive spotting depth.
- For a following twist drill, make the spotting diameter slightly larger than the drill’s web thickness.
- Reduce cutting speed and feed when machining harder materials or using extended-length tools.
Recommended Applications
- Accurate hole positioning
- Spot drilling
- Starting holes for twist drills
- Countersinking
- 45° edge chamfering
- Removing sharp edges
- CNC machining centers
- Mold and die components
- Automotive components
- Precision mechanical parts
Machining Advantages
Reduced Drill Wandering
The rigid 90° point establishes a precise starting location for the following drill.
Stable Cutting Performance
Balanced two-flute geometry reduces vibration and supports consistent machining.
Improved Hole Position Accuracy
The short cutting section minimizes deflection and improves repeatability.
Multiple Machining Functions
One cutter can perform spot drilling, positioning, countersinking and chamfering.
Extended Tool Life
The combination of solid carbide and a wear-resistant coating helps maintain cutting-edge performance during steel machining.
Available Customization
- Cutter diameter
- Point angle
- Cutting-edge length
- Shank diameter
- Overall length
- Long-reach design
- Carbide grade
- Golden coating
- Black or blue nano coating
- Internal coolant design
- Dimensional tolerance
- OEM laser marking
- Private-label packaging
- Customized tools according to drawings
Ordering Information
Please provide the following information when requesting a quotation:
- Cutter diameter
- Point angle
- Shank diameter
- Overall length
- Workpiece material and hardness
- Machining operation
- Required coating
- Internal coolant requirement
- Dimensional tolerance
- Order quantity
Our technical team can recommend suitable tool dimensions and initial cutting parameters according to your application.
PENGFU TOOLS
Changzhou Pengfu Tools Co., Ltd.
Solid Carbide Cutting Tools and Custom CNC Tool Solutions
Get a Quote for Your Spot Drills
Contact PENGFU TOOLS for product selection, cutting parameters, customized dimensions and a competitive quotation.
