8615370360250
sales@gmindustry.cn
enEnglish
Category
Your Professional Step Drill Bit Supplier

 

Danyang GM Tools Co., Ltd., located in Danyang City, Jiangsu Province, China, is a professional manufacturer of precision cutting tools. Our modern 8,000 m² factory is equipped with advanced CNC machines, precision grinders, and heat-treatment equipment. Our experienced team of engineers, production staff, and quality inspectors ensures high-quality manufacturing and strict quality control. We specialize in standard and customized twist drills, power tools, saws, and hand tools for industrial applications such as metalworking, machinery, automotive, and mold making. With an overseas plant in Malaysia, we support global customers by reducing import costs and ensuring timely delivery. We are committed to reliable, long-term partnerships.

 

 
 
Why Choose Us

Sales Market

Our products are exported to numerous regions—including the Americas, Europe, the Middle East, and Asia—where they have garnered widespread acclaim.

Our Certificate

ISO 9001, CE, and RoHS certified, with 100% quality guarantee and strict quality control processes.

OEM/ODM Capability

Customized solutions provided quickly by our dedicated engineering team according to client specifications.

Quality Assurance

We provide a 100% quality guarantee to our customers. Any quality issues are fully our responsibility, ensuring reliable and worry-free products.

 

3PCS HSS Black and White Finish Step Drill Bit Set

3PCS HSS Black and White Finish Step Drill Bit Set is a versatile collection of multi-diameter drill bits designed to create clean, precise holes in various materials—especially metals. These tools feature a conical design with multiple stepped diameters, allowing users to drill different-sized holes without changing bits. Ideal for metalworking, automotive repair, HVAC, and DIY projects, step drills save time, reduce tool clutter, and improve efficiency.

 

Name

3PCS HSS black and white finish step drill bit set

Material

HSS 4241, HSS 4341, HSS M2(6542) and M35 for choose.

Flute

Double straight flute.

Tip degree

135 degree with split point

Surface treatment

Black and white finish

3PCS HSS black and white finish step drill bit set size

Metric size from 4 to 30mm by increment 2mm; from 4 to 20mm by increment 2mm; from 4 to 12mm by increment 2mm;

Mark

Mark size on flute by lasering. And mark LOGO or brand on shank.

Shank

Round/straight shank with Tri-flats.

Package

3PCS packed in a grey plastic rose box; we also have other box and package for you choose;

Brand

GMTOOL, We also accept custom customers' brand (OEM).

 

3PCS HSS Black And White Finish Step Drill Bit Set

 

Advantages of 3PCS HSS Black and White Finish Step Drill Bit Set

Multisize Capability: The conical, stepped design allows the bit to drill multiple hole diameters without changing tools—simply go deeper into the next step for a larger hole.

 

Clean, Burr-Free Holes: The cutting geometry shears material cleanly, reducing jagged edges (burring) around the hole. This is especially important in metalwork and finishing projects where smooth edges are required.

 

Reduced Heat Buildup: The gradual cutting action spreads heat across multiple flutes, helping prevent overheating compared to standard bits that cut all at once.

 

Versatility Across Materials: Effective on sheet metal, aluminum, copper, plastic, acrylic, and even fiberglass—making them ideal for mixed-material projects.

 

Deburring Function: Some users lightly reverse the bit to smooth out the hole edge, effectively using it as a deburring tool.

 

Types of 3PCS HSS Black and White Finish Step Drill Bit Set
 

Metal Step Drill Bits

Engineered specifically for drilling through metals like aluminum, brass, mild steel, and copper. These bits are typically made from hardened high-carbon steel or alloyed tool steel to withstand the high friction and heat generated during metal drilling.

Cobalt Step Drill Bits

Made from a high-speed steel (HSS) alloy containing 5–8% cobalt (M35 or M42 grade), these bits offer superior heat resistance and hardness. The cobalt enhances the bit’s ability to maintain sharpness at elevated temperatures, making it ideal for aggressive drilling in tough materials.

Titanium-Coated Step Drill Bits

These bits are typically made from HSS and coated with a thin layer of titanium nitride (TiN), giving them a distinctive gold finish. The coating reduces friction, increases surface hardness, and improves heat dissipation, significantly extending tool life.

Spiral Flute Step Drill Bits

Featuring a helical or spiral flute design, these bits are optimized for efficient chip removal and smooth cutting action. The spiral geometry pulls debris upward and out of the hole, preventing clogging and ensuring consistent performance, especially in deep or continuous drilling.

 

 
Uses of 3PCS HSS Black and White Finish Step Drill Bit Set
 
01/

Drilling Holes in Sheet Metal
Step drill bits are exceptionally effective for creating clean, accurate holes in thin sheet metal. Unlike traditional twist bits that can grab or tear the material, step bits cut smoothly with minimal force, reducing the risk of deformation.

02/

Punching Through Aluminum
Aluminum is prone to work hardening and galling, which can dull standard bits quickly. Step drill bits excel in aluminum due to their gradual cutting edges and reduced friction.

03/

Creating Openings in Plastics
Drilling plastics like acrylic, polycarbonate, or ABS requires precision to avoid cracking or melting. Step drill bits provide controlled material removal, ensuring smooth, polished edges.

04/

Making Holes in Wood
While not the primary tool for woodworking, step drill bits perform well in thin plywood, MDF, and laminated boards where clean entry and exit holes are required.

05/

Enlarging Existing Holes
One of the standout features of step drill bits is their ability to gradually enlarge pre-drilled holes without damaging surrounding material.

06/

Multi-Material Versatility
Step drill bits are engineered for use across a wide range of materials, making them a go-to tool for technicians and fabricators who work with mixed media.

 

Material Composition of 3PCS HSS Black and White Finish Step Drill Bit Set

 

1

High-Speed Steel (HSS)

Ideal for soft materials like wood, plastic, and thin aluminum. Affordable and widely available, but less durable under high heat or prolonged use.

2

Cobalt-Alloyed Steel (HSS-Co)

Contains 5–8% cobalt, offering superior heat resistance and hardness. Perfect for drilling stainless steel, cast iron, and other tough metals. Resists dulling even during extended use.

3

Titanium-Nitride Coated (TiN)

Features a gold-colored coating that reduces friction, increases hardness, and improves chip ejection. Extends bit life and maintains sharpness longer than standard HSS.

4

Black Oxide Coated

Provides mild corrosion resistance and improved heat absorption. Suitable for general-purpose metal drilling.

 

Cutting Edge and Flute Design of 3PCS HSS Black and White Finish Step Drill Bit Set
 
 

Sharp Cutting Edges

Each step should have a precisely ground cutting lip to ensure clean hole entry and exit. Dull edges cause burring and require more force.

 
 

Centering Point or Pilot Tip

Many step bits feature a small pilot point on the smallest step to prevent walking or slipping when starting a hole.

 
 

Helical Flutes

Efficiently remove metal chips (swarf) from the hole, preventing clogging and overheating. Deeper, wider flutes are better for aggressive metal drilling.

 
 

Chip Breakers

Some advanced bits include notches or grooves that break long metal shavings into smaller pieces for easier ejection.

 

 

Usage Tips of 3PCS HSS Black and White Finish Step Drill Bit Set

 

Hole Enlargement

Begin with the smallest step that fits into the existing hole, then gradually move to larger steps until the desired diameter is achieved. This ensures smooth, concentric enlargement without tearing the material.

01

New Hole Drilling

Start with pilot holes if needed, especially in thicker or harder materials. The tapered tip naturally centers itself, reducing the need for precise marking.

02

Material Versatility

Ideal for drilling copper, aluminum, brass, mild steel, stainless steel (with cobalt bits), plastic, and composite panels.

03

Speed and Feed

Use lower RPMs (800–1,500) for hard metals and higher speeds (2,000–3,000) for softer materials. Apply steady, moderate pressure—let the bit do the cutting.

04

Cooling

Use cutting fluid or lubricant when drilling metal to reduce heat buildup, prevent work hardening, and extend bit life.

05

 

Maintenance Tips

 

Use Cutting Fluid: Especially when drilling metal, apply cutting oil or coolant to reduce heat buildup and extend bit life.

1

>>

Avoid Overheating: Pause periodically during long drilling sessions to let the bit cool down and prevent temper loss in coated bits.

2

>>

Clean After Use: Remove metal shavings and residue with a brush to maintain flute efficiency and prevent corrosion.

3

>>

Store Properly: Keep bits in a dry, organized case to avoid damage to cutting edges and coating.

4

>>

Replace When Dull: Don’t continue using a bit that produces rough holes or requires excessive pressure—dull bits increase the risk of breakage and poor results.

5

 

 

FAQ

 

Q: Is OEM available?

A: Yes,OEM and customization are availble. Also, we can provide label printing service.

Q: Are samples available?

A: Yes, you can ask some samples for testing after confirming our prices, but please pay the freight fee,the fee will be returned to you after you making official order.

Q: What is your payment terms?

A: T/T,L/C,Paypal for different circumstances.

Q: What's your deliver way?

A: Express delivery, air shipping, sea shipping are available for your request.

Q: What's your delivery time?

A: Usual delivery time is 20-30 days after receiving the advance payment.
For the customized product, the delivery time is 35-45 days after receiving the advance payment.

We're well-known as one of the leading step drill bit manufacturers and suppliers in China, also support customized service. Please feel free to buy high quality step drill bit made in China here from our factory. Contact us for free sample.

1 2 step bit, step bits for metal, 1 step drill bit
Popular Products
Send Inquiry