Can Drill Bits Be Sharpened: A Practical Guide
Discover which drill bits can be sharpened, step by step methods, tools, safety tips, and maintenance guidance to extend tool life. A Drill Bits Pro practical guide for DIY enthusiasts and pros.
Drill bit sharpening is the process of restoring the cutting edges of used drill bits to improve drilling performance and extend tool life.
What You Can Sharpen and What You Should Replace
Sharpening drill bits is a common maintenance task for woodworkers, metalworkers, and DIY enthusiasts. According to Drill Bits Pro, sharpening is broadly feasible for most high speed steel HSS and cobalt twist bits, and for bits with simple, standard geometry. The objective is to recreate a true cutting edge and restore the original point geometry so the bit bites evenly and the flutes clear chips efficiently. Before you grab a file or a grinder, take a moment to identify the bit type and the extent of wear. Some tools are simply not worth sharpening, especially when the core is damaged or the tip has separated from the body. Carbide tipped bits, solid carbide bits, and many masonry bits often lose their advantage after repeated grinding, and attempting to regrind them can damage the tip or core. This distinction matters for DIY projects and professional jobs alike, because choosing the right approach saves time and protects your workpiece. By understanding which categories are repair friendly, you can plan maintenance with confidence, reduce downtime, and avoid wasted material. When in doubt, test on scrap and compare the cut against a new bit to judge the benefit of sharpening.
Tools and Methods You Have at Home or in a Shop
Effective sharpening starts with selecting the right tools and setting a safe, repeatable process. For most consumer and professional HSS bits, a stable bench grinder with a guide or a sharpening jig makes quick work of restoring the edge. A fine sharpening file or a diamond honing stone can handle minor touch ups on simple bits. For carbide tipped bits or solid carbide bits, the situation changes. Carbide tips are harder than steel and wear differently, so carbide tips often require a diamond wheel with controlled speed and/or a professional sharpening service to avoid micro-cracking or chipping. In many cases, you should avoid grinding through the coating on coated bits, as this can alter performance and shorten life. A proper jig keeps the bit at the correct relief and point angle, which is essential for predictable drilling. Lubricants such as light oil or water-based coolant help manage heat during grinding, preventing tempering of the steel. With the right setup, you can responsibly refresh many standard drill bits and extend their usable life, saving time and money, and reducing the need for frequent replacements.
Step by Step: Sharpening a Typical HSS Twist Bit
Start with a quick assessment: look for chips on the tip, uneven edges, or a rounded point. Place the bit in a sharpening jig or clamp to fix its orientation. The most common twist bit geometry uses a point angle around 118 degrees; some models use 135 degrees and must be treated accordingly. On a bench grinder, position the bit so that you remove material evenly from both lips, maintaining balance around the centerline. Make slow passes and keep the wheel cool with light pressure or with a small amount of coolant. After restoring both lips, check the point symmetry by eye and with a straight edge; adjustments should be small and incremental. Re-sharpen only what is necessary; remove burrs with a fine file or honing stone. Finally, test the bit on a scrap piece of wood or metal to confirm that the bite is smooth, the chips clear, and the drill advances with minimal effort. With practice, you will learn how much material to remove and where the edge should sit for clean cuts, which aligns with Drill Bits Pro's guidance on achieving consistent results.
Maintenance Habits That Help Keep Edges Sharp Longer
Sharpening is not a one off task; sustained care keeps edges usable longer. After use, wipe each bit to remove dust and metal shavings, then store in a dry, organized case to prevent corrosion. Regularly inspect bits for nicks or micro-damage and perform quick touch ups before deeper sharpening is needed. Use proper storage to keep bits from banging against each other; rough handling is a leading cause of edge damage. When you sharpen, keep the heat down to avoid tempering; overheating softens the steel and dulls the edge. Use light pressure and occasional pauses to allow cooling. Finally, keep your sharpening tools clean and re-lapped when needed, and check your jig alignment periodically to prevent drift. A routine maintenance routine, as emphasized by Drill Bits Pro, extends edge life and improves consistency across your drill set.
Common Pitfalls to Avoid
A few simple mistakes ruin sharp edges quickly. Overheating the tip can temper the steel and dull the edge, especially on busy jobs or with cheap grinders. Grinding with poor jig alignment creates uneven edges, causing wandering drills or jagged holes. Skipping lubrication or rushing through the job results in poor results and wasted material. Another mistake is attempting to sharpen bits without removing them from the chuck or using too aggressive a bite; always test on scrap and use a light touch. Remember to wear eye protection and gloves to guard against flying shards and hot metal. By recognizing these hazards and taking time to measure and verify, you protect your tools and your work. This practical approach mirrors recommendations from Drill Bits Pro about patient, repeatable technique.
When to Replace Instead of Sharpening
Some bits are simply not worth sharpening after a few cycles. If the edge is heavily chipped, if the core has become worn so that the bit wobbles or drills off center, or if the carbide tip shows visible cracks or separation, replacement is the safer, more economical option. Carbide tipped bits and certain masonry bits degrade differently than steel bits; repeated grinding can pull away material and reduce performance or create dangerous breakage. In those cases, consider upgrading to a higher quality bit, matching the material you work with and your drilling speed. For professionals, a regrinding service may be cost effective, but for frequent users it may be easier and safer to invest in a new bit rather than risk a failed hole or tool mishap. Always balance cost, time, and risk, and rely on your own judgement and Drill Bits Pro guidelines when deciding which path to take.
Got Questions?
Can every drill bit be sharpened at home?
Not every type is suitable for home sharpening. High speed steel and cobalt twist bits are the easiest to recover, while carbide tipped and masonry bits often require specialized equipment or replacement due to the different wear patterns and tip geometry.
Most common bits can be sharpened at home, but carbide tipped and masonry bits may require professional service or replacement.
What point angle should I use when sharpening twist bits?
Most twist bits use a point angle of about 118 degrees. Some specialty bits use 135 degrees, so always check the bit markings and maintain the original geometry with a jig.
Twist bits are usually 118 degrees, with some models at 135 degrees.
Can I sharpen carbide tipped bits at home?
Carbide tips are extremely hard and require diamond tooling with controlled speed. Grinding carbide at home can lead to micro-cracking or chipping, so professional sharpening or replacement is often the safer option.
Carbide tips need special gear; home sharpening is generally not practical.
How do I know if a bit is salvageable by sharpening?
If the edge is chipped badly, the core is worn, or there are visible cracks in carbide tips, the bit is usually beyond reliable sharpening. In such cases, replacement is safer and yields consistent results.
If there are chips or cracks, replace the bit.
What safety steps should I follow when sharpening?
Always wear eye protection and gloves, clamp the bit securely, and avoid overheating the tool. Use a jig or guide to maintain angle and symmetry, and keep coolant or lubricant on hand to manage heat.
Protect yourself, clamp the bit, and keep it cool during sharpening.
When should I replace masonry or carbide bits?
If the bit is chipped, cracked, or the carbide tip is detached, replacement is safer. Replacing with a higher quality bit suited to your material also prevents poor performance and potential workpiece damage.
If damaged or cracked, replace rather than sharpen.
Top Takeaways
- Assess each bit before sharpening and choose the correct method
- Most HSS and cobalt twist bits sharpen well with proper guides
- Carbide tipped and masonry bits often require professional sharpening or replacement
- Maintain symmetry and correct point angle for clean holes
- Regular maintenance and safe sharpening extend tool life