Looking for the perfect drill bit size for your next project? The 29/64 drill bit offers the ideal balance between strength and precision, making it a must-have in any toolbox. This shopping guide breaks down what makes the 29/64 drill bit essential for both DIYers and professionals, helping you choose the right option for efficient, accurate drilling every time.
Comparing Types and Variations of 29/64 Drill Bits
| Type | Material | Surface Coating | Point Style | Applications | Typical Price Range | Durability |
|---|---|---|---|---|---|---|
| High-Speed Steel (HSS) – Uncoated | HSS | Uncoated | Standard/Split | General metals, woods, plastics | $9.70 – $10.80 | Good |
| High-Speed Steel (HSS) – Black Oxide | HSS | Black Oxide | Split | Steel, iron, stainless steel | $12.30 – $14.80 | Very Good |
| HSS – Titanium Nitride (TiN) Coated | HSS | Titanium Nitride | Split | Hardened steel, non-ferrous metals | $18.35 – $26.07 | Excellent |
| HSS – Titanium Aluminum Nitride (TiAlN) Coated | HSS | TiAlN | Split | Tool steel, titanium, fiberglass | $37.33 | Superior |
| Solid Carbide | Carbide | Uncoated/Various Coatings | Split/Other | Hard materials, precision work | $35+ | Exceptional |
| Cobalt Alloy | Cobalt–HSS Blend | Uncoated/Various Coatings | Split | Stainless, tough alloys | $18+ | Very High |
| Jobber Length | Any | Any | Any | All-purpose use | Varies | Varies |
| Stub/Short Length | Any | Any | Any | Precision, rigid drilling | Varies | Varies |
| Extended Length | Any | Any | Any | Deep/reach applications | $23+ | Varies |
Everyday Usage of the 29/64 Drill Bit
What is a 29/64 Drill Bit Used For?
A 29/64 drill bit is a fractional-size bit—0.4531 inches in diameter—commonly used in metalworking, woodworking, construction, automotive, and fabrication. It is especially important for:
- Creating clearance holes for bolts and fasteners.
- Pre-drilling for tapping 1/2″-13 threads (typical in mechanical and building trades).
- Making precision holes for bushings, fittings, and frame assemblies.
- Enlarging existing holes without compromising material integrity.
Where Will You Encounter This Size?
You’ll commonly encounter the 29/64 drill bit when:
- Assembling heavy-duty machinery or structural frameworks.
- Installing or replacing industrial hardware.
- Working with thick steel, aluminum, or hardwoods requiring sturdy, precise holes.
Benefits of Owning a 29/64 Drill Bit
Versatility and Convenience
- One-stop size for many industrial and mechanical needs: It matches closely with standard bolt and thread requirements, such as clearance holes for 1/2″ bolts.
- Reduces the need for oversized reaming: Its accuracy minimizes the risk of loose fittings.
- Wide compatibility: Available in multiple shank types and lengths for hand and drill press usage.
Material and Coating Options
- Adaptable to different tasks: You can select the material and coating to best suit your project—whether drilling mild steel, tough alloys, or composite materials.
- Long-lasting performance: High-quality coatings like TiN and TiAlN deliver longer tool life and better finishes.
Time and Effort Savings
- Minimize work interruptions: The right bit prevents unnecessary tool changes or extra steps.
- Fewer broken bits: Premium bits (like cobalt and solid carbide) withstand more heat and wear.
How to Choose the Right 29/64 Drill Bit for Your Job
1. Match the Bit Material to Your Workpiece
- High-Speed Steel (HSS): Ideal for everyday use in non-hardened metals, wood, and plastic.
- Cobalt Alloy: Best for stainless steel, cast iron, and other tough metals.
- Solid Carbide: Recommended for hard metals, high-speed and high-precision CNC work.
- Carbide-Tipped: Offers enhanced durability with cost-efficiency for masonry and composites.
2. Select the Suitable Coating
- Uncoated: Budget-friendly and works well on wood and soft metals.
- Black Oxide: Provides rust resistance and lower friction; resists heat better than bare HSS.
- Titanium Nitride (TiN): Greatly improves wear resistance and drill speed.
- Titanium Aluminum Nitride (TiAlN): Best for extended life, high-temperature, and hard-material drilling.
3. Consider Drill Bit Length
- Jobber Length: Standard for most general purposes—good reach and rigidity.
- Stub/Screw Machine Length: Shorter, less flexing—ideal for precision/automated applications.
- Extended/Aircraft Length: For deep or hard-to-reach holes.
4. Point Style Makes a Difference
- Standard Point: For most general drilling.
- Split Point: Self-centering—a great choice when you need a precise start or are drilling harder materials.
- Pilot Point: Reduced walking, cleaner entry, used in premium wood and metal bits.
5. Shank Style
- Round Shank: Universal, fits most chucks.
- Reduced Shank: Allows you to use large bits in smaller-capacity drills.
- Hex Shank: Quick change capability for impact drivers.
6. Evaluate Your Budget and Project Frequency
- If you drill often or in demanding materials, invest in premium bits. For occasional/prototyping use, standard HSS may suffice.
Tips, Advice, and Best Practices
Selection Tips
- Know your material: Harder materials need harder bits and better cooling. Match accordingly.
- Choose the right point: Split points help prevent the bit from wandering, reducing the need for a pilot hole.
- Don’t overspend unnecessarily: For wood or plastic, you can opt for HSS or even uncoated bits.
Usage Best Practices
- Use the right drill speed: Slower speeds for hard metals; faster for soft materials.
- Secure your workpiece: Use clamps or a vise to prevent spinning and injury.
- Apply lubrication: Use cutting oil for metals to prolong bit life and improve cut quality.
- Avoid excessive pressure: Let the bit do the work to prevent breakage.
- Back the bit out regularly: Especially with deep holes, to clear chips and prevent jamming/overheating.
- Inspect your bit before use: Look for dull edges, chips, or damage.
- Sharpen when needed: Dull bits are unsafe and imprecise. Invest in a sharpener or replacement.
- Store properly: Keep drill bits dry and in cases/pouches to prevent rust or accidental damage.
- Change bits appropriately: Use quick-change shanks for fast-paced jobs to save time.
- Always use the correct chuck or adapter: To ensure safe and accurate operation.
Technical Feature Comparison Table
| Feature | HSS Uncoated | HSS Black Oxide | HSS TiN-Coated | HSS TiAlN-Coated | Cobalt Alloy | Solid Carbide |
|---|---|---|---|---|---|---|
| Size | 29/64″ (0.4531″) | 29/64″ (0.4531″) | 29/64″ (0.4531″) | 29/64″ (0.4531″) | 29/64″ (0.4531″) | 29/64″ (0.4531″) |
| Decimal Equivalent | 0.4531″ | 0.4531″ | 0.4531″ | 0.4531″ | 0.4531″ | 0.4531″ |
| Standard Length | 5 5/8″ | 5 5/8″ | 5 5/8″ | 5 5/8″ | 5 5/8″ | Varies |
| Short Length (Stub) | 3 5/8″ | 3 5/8″ | 3 5/8″ | — | 3 5/8″ | — |
| Extended Length | 7 – 12″ | 7 – 12″ | — | — | — | — |
| Max Drilling Depth | 3.5″ (jobber) | 3.5″ (jobber) | 3.5″ (jobber) | 3.5″ (jobber) | 3.5″ (jobber) | Varies |
| Shank Type | Round | Round | Round | Round | Round/Reduced | Round |
| Point Style | Standard | Split | Split | Split | Split | Split |
| Usage Materials | Mild steel, plastics | Steel, iron, stainless | Hardened steel, plastics | Tool steel, titanium, fiber | Tough alloys | Hardest metals |
| Wear Resistance | Standard | Improved | High | Highest | Very High | Top |
| Heat Resistance | Standard | Good | Excellent | Highest | Excellent | Exceptional |
| Price (est.) | $9.70 – $10.80 | $12.30 – $14.80 | $18.35 – $26.07 | $37.33 | $18+ | $35+ |
Related Video
Conclusion
A 29/64 drill bit is a key player in any toolkit—whether you’re tackling heavy machine assembly, fabricating sturdy structures, or simply aiming for precise, clean holes in tough materials. With numerous versions available in various materials, coatings, lengths, and point styles, choosing the right 29/64 drill bit hinges on knowing your workpiece, budget, and project needs.
Investing in the right type ensures greater productivity, safety, and professional results. By understanding the strengths of each bit type and following proven user strategies, you’re sure to get the best performance and value out of your 29/64 drill bit.
FAQ
-
What is the exact diameter of a 29/64 drill bit?
A 29/64 drill bit measures exactly 0.4531 inches (11.510 mm) across its widest point. -
Can I use a 29/64 drill bit for both metal and wood?
Yes, most 29/64 drill bits are designed for versatility. For frequent metal use, choose bits coated with black oxide, TiN, or made of cobalt; for wood, any HSS or coated bit will suffice. -
What size tap should be used after drilling with a 29/64 bit?
A 29/64 bit is ideal for tapping a 1/2″-13 UNC thread, making it a standard pre-tap size in fabrication. -
What is the difference between jobber, stub, and extended-length 29/64 bits?
- Jobber length: Standard, good for most uses.
- Stub length: Short, for precise or shallow drilling.
-
Extended/aircraft length: Long, for deep or hard-to-access holes.
-
What coating should I choose for drilling stainless steel?
Use a cobalt alloy bit or a high-speed steel bit coated with TiN or TiAlN for best results in stainless steel due to their enhanced wear and heat resistance. -
Do I need to use cutting oil with a 29/64 bit?
Cutting oil is recommended when drilling metals to reduce heat, prevent premature dulling, and produce cleaner holes. It’s usually not needed for wood or plastics. -
How do I prevent a 29/64 bit from walking (slipping on start)?
Choose a split point or pilot point bit for self-centering performance. For standard points, create a dimple with a center punch before drilling. -
Can I use a 29/64 bit in a handheld drill?
Yes, but due to its size, ensure your drill is powerful enough and has a securely tightened chuck. Drilling at lower speeds and using the right bit for the material is essential. -
How do I sharpen a dull 29/64 drill bit?
You can use a bench grinder, dedicated drill bit sharpener, or have it professionally sharpened. Maintaining the original angle and point style is important for safe and effective performance. -
How do I store my 29/64 drill bits to prevent rust and damage?
Store them in a dry, organized case or drill index. Clean after each use and lightly oil if storing for extended periods to prevent corrosion.
This comprehensive guide is designed to help you confidently navigate the range of 29/64 drill bits, matching the right tool to the job for results that impress.