Drill Bits 101: Choosing the Right Bit for the Job

Drill Bits 101: Choosing the Right Bit for the Job

Your comprehensive guide to drill bit selection for professional results

When it comes to fastening and fabrication, the quality of your drill bits can make or break the job—literally. Whether you’re drilling through wood, metal, plastic, or other industrial materials, selecting the correct drill bit in terms of size, coating, and hardness is crucial for performance and longevity. At SC Fastening Systems, we proudly stock Consolidated Toledo Drill products, a trusted name in American-made drill bit manufacturing known for consistency, durability, and precision.

Understanding Drill Bit Sizes

Drill bits come in a wide range of sizes to accommodate the diverse needs of industrial and commercial professionals. Standard sizes include:

  • Fractional Sizes: Common in the U.S., ranging from 1/64″ to 1-1/2″
  • Wire Gauge Sizes: Identified by numbers (#80 to #1 and then #1 to #60), used in precise applications
  • Letter Sizes: Ranging from A to Z, often used in aerospace and specialty industries
  • Metric Sizes: Ranging from 0.2 mm up to over 25 mm, preferred in international standards

Knowing which sizing system your job requires helps ensure tight tolerances and secure fastening.

Coatings: More Than Just Color

Coatings significantly enhance the life and functionality of a drill bit. Common coatings include:

  • Black Oxide: Ideal for general-purpose drilling in wood or soft metals, offering corrosion resistance and extended life
  • Titanium Nitride (TiN): Great for high-speed drilling in hardened materials; provides excellent wear resistance
  • Cobalt: Not a coating, but a material often blended into high-speed steel (HSS) to improve heat resistance—excellent for drilling stainless steel and other tough alloys
  • Carbide Tipped: Perfect for hard materials like masonry, tile, or even hardened steel
  • Uncoated (Bright Finish): Best for non-ferrous metals and plastics where coating isn’t needed

At SC Fastening Systems, our Consolidated Toledo Drill line includes TiN-coated, cobalt, and black oxide drill bits to meet a wide range of industrial needs.

Hardness and Material Composition

Different applications require drill bits of different hardness levels:

  • High-Speed Steel (HSS): Durable and affordable, HSS bits are great for wood, plastic, and softer metals
  • Cobalt (M35 or M42): Provides added hardness and temperature resistance—ideal for stainless steel and cast iron
  • Solid Carbide: Extremely hard and brittle; excellent for precision applications in extremely hard materials
  • Carbide-Tipped: Offers the best of both worlds—hardness for cutting and flexibility in the shank

Consolidated Toledo Drill offers premium HSS and cobalt options, ensuring users have access to the right bit for every material.

Applications by Industry

The versatility of drill bits spans multiple industries:

  • Manufacturing & Fabrication: For CNC and manual drilling operations in metals
  • Construction: Wood frame drilling, metal studs, and concrete anchoring
  • HVAC & Electrical: Precision drilling for ducting, conduit, and panel work
  • Aerospace & Automotive: Demanding applications that require tight tolerances and specialized coatings

Choosing the Right Drill Bit Style

  • Jobber Length Bits: Most common, offering a balance between strength and reach
  • Stub/Screw Machine Length: Shorter bits used in applications where rigidity is important
  • Mechanics Length: Intermediate length, great for use in hand drills
  • Extended/Extra Length: For deep hole drilling or hard-to-reach spots

The Consolidated Toledo Drill Advantage

Established in the U.S., Consolidated Toledo Drill has built a reputation for delivering precision-crafted drill bits made from high-quality materials. Whether you’re looking for a standard HSS bit f