If you're a machinist, metalworker, or even a hands-on DIYer, you’ve probably faced the frustration of a dull High-Speed Steel (HSS) drill bit. Replacing bits frequently isn’t just costly—it’s wasteful. The good news? You can sharpen your HSS drill bits at home, even without specialized industrial tools.
This article will guide you through practical, safe, and proven methods for restoring cutting performance to your HSS drill bits using commonly available equipment.
HSS drill bits—especially cobalt or M42 variants—aren’t disposable items. They’re designed to be resharpened multiple times. According to Sandvik Coromant’s cutting tools guide, proper regrinding can restore up to 90% of a tool’s original performance, assuming the core structure hasn’t overheated or fractured.
Extend tool life
Save money on replacements
Achieve cleaner, more accurate drilling
Maintain productivity with fewer delays
To sharpen HSS drill bits at home, the following tools are commonly used:
Bench grinder (ideally with a fine grit wheel—60 to 100 grit aluminum oxide)
Eye protection and gloves
Coolant or water for quenching
Drill bit gauge or protractor (to check angles)
Tip from Practical Machinist forums: Use a dressing stone on your bench grinder to keep the surface clean and reduce vibration for more accurate grinding.
The standard point angle for most HSS drill bits is 118°. For tougher materials like stainless steel, it may go up to 135°. Maintaining a symmetric tip is critical for proper cutting and hole accuracy.
Wear eye protection.
Make sure the grinder is bolted down and stable.
Keep a cup of water nearby for quenching.
Hold the bit at roughly a 60° angle to the grinding wheel surface.
Maintain a firm grip but don’t force the bit into the wheel.
Start with the cutting lip. Each side must be sharpened evenly to avoid drilling off-center.
Gently touch the lip to the wheel.
Rotate slightly while grinding to preserve the curvature.
Frequently quench the bit in water to avoid overheating. Overheating can ruin the bit’s hardness—especially if it turns blue or purple.
Use a drill gauge or visual inspection to ensure both cutting lips are:
The same length
The same angle
Symmetrical about the centerline
Asymmetry causes uneven cutting and shortens tool life.
After grinding:
Try drilling into a scrap material (e.g., mild steel).
If it cuts cleanly without wobble or squeal, your sharpening is successful.
If the bit walks, squeals, or overheats quickly—go back and recheck symmetry and angles.
For more consistent results, especially for beginners, you can use a sharpening jig or drill doctor. These tools guide the bit into position, controlling both angle and symmetry.
Popular models include:
Drill Doctor 750X
Tormek DBS-22 (for high-end users)
According to user reviews from FineWoodworking.com, sharpening jigs reduce the learning curve significantly and offer factory-like results with minimal skill required.
Once your drill bit is sharp again:
Store it in a dry, organized case
Label sharpened bits if using different angles
Always use cutting fluid or coolant when drilling metals to prolong sharpness
Avoid excessive speed to reduce heat buildup
Sharpening HSS drill bits at home doesn’t require a machinist’s shop—just a bit of knowledge, practice, and patience. By learning to regrind your tools correctly, you can:
Save money
Reduce downtime
Get cleaner, faster results in all your drilling tasks
Whether you’re maintaining tools for your workshop or small business, mastering this skill is a game-changer.
Contact our experts today for a free quote or technical consultation.