US Dollars
This category includes fractional drill bits ranging from 1/8" up to 7/8" diameter, covering the most commonly used sizes for automotive service and repair work. You'll find both jobber length bits for standard applications and reduced shank designs that allow larger diameter bits to fit standard 1/2" drill chucks.
Understanding Drill Bit Types in This Range
Jobber Length Bits: Standard-length bits typically used for general-purpose drilling in metal, wood, and plastic. These are ideal for most automotive repair tasks including drilling out broken bolts, creating mounting holes, and general fabrication work.
Reduced Shank Bits: Larger diameter bits (generally 9/16" and above) with a 1/2" shank allow you to drill bigger holes without requiring a larger drill chuck. These are essential for body shop work, metal fabrication, and creating larger bolt holes. The three-flatted shank design provides superior grip and prevents slippage in keyless chucks.
Material Construction & Applications
Drill bits in this category are typically constructed from high-speed steel (HSS) in various grades, each suited to different applications:
- M-2 High Speed Steel: Offers an excellent balance of strength, heat resistance, and wear resistance for general-purpose drilling in automotive materials
- M-7 High Speed Steel: Features higher vanadium content for increased abrasion resistance during heavy-duty drilling applications common in metal fabrication and collision repair
- Cobalt Steel (M-42): Contains approximately 5% cobalt for superior heat and abrasion resistance when drilling hard metals, stainless steel, and high-tensile strength materials
Point Geometry and Performance Features
The point angle significantly affects drilling performance. Most bits in this range feature either 118° or 135° point angles:
- 118° Standard Point: Versatile angle suitable for wood, metal, and plastic applications commonly encountered in automotive work
- 135° Split Point: Self-centering design that begins drilling immediately with minimal "walking," reducing the need for center punching and producing more accurate hole placement
Split point designs generally offer faster penetration and reduce user fatigue during extended drilling operations, making them preferred for production environments and heavy-duty applications.
Common Automotive Service Applications
- Drilling out broken exhaust studs, bolts, and fasteners
- Creating mounting holes for accessories and aftermarket components
- Body panel repair and custom fabrication work
- Frame repair and modification
- Enlarging existing holes for upgraded hardware
- Maintenance, repair, and operations (MRO) tasks in service bays
- Heavy-duty metal drilling for collision repair
Selecting the Right Bit for Your Application
When choosing a drill bit from this range, consider the material you'll be drilling, the frequency of use, and the precision required. For occasional general repair work, standard M-2 high-speed steel bits typically provide adequate performance. For shops that regularly drill hard metals or work with stainless steel components, cobalt bits offer extended tool life and superior performance despite their higher initial cost.
Reduced shank bits are essential when your application requires holes larger than 1/2" but you're working with standard portable drills or drill presses with 1/2" chucks. The three-flatted shank design ensures secure grip and prevents the dangerous spinning that can occur with round shanks under heavy torque loads.
Safety and Best Practices
Important Safety Reminders:
- Always wear safety glasses when operating drill equipment
- Secure workpieces properly before drilling to prevent spinning or movement
- Use appropriate cutting speeds for the material and bit size
- Ensure bits are properly seated and tightened in the chuck before operation
- Allow bits to cool between heavy-duty drilling operations
- Inspect bits regularly for wear, damage, or dull cutting edges
Using cutting fluid or lubricant appropriate for your material can significantly extend bit life and improve hole quality, particularly when drilling metal. For automotive applications, this is especially important when working with hardened steel or stainless components.
Specifications vary by model. Always check individual product listings and manufacturer documentation for exact details regarding dimensions, materials, and recommended applications.