What is the best tool to sharpen lathe tools?

Having sharp lathe tools is critical for woodturning. Dull tools make the process more difficult and can result in tear-out, catches, and poor finishes. There are a variety of methods and tools available for sharpening lathe chisels and gouges. Choosing the right sharpening system depends on your needs, skills, budget and workshop setup.

Why Sharp Lathe Tools Are Important

Sharp tools are essential in woodturning for several reasons:

• Sharp edges cut cleanly through wood fibers instead of tearing them out, resulting in a smoother finish.
• Sharp tools require less force to push through the wood. This puts less strain on the turner and reduces fatigue.
• Sharp edges stay cleaner by cutting shavings instead of crushing and burnishing the wood.
• A sharp edge is safer and less likely to catch or dig into the wood unexpectedly.
• Properly sharpened bevels support the edge correctly, improving cutting action and control.

In contrast, dull tools:

• Tear out wood fibers instead of slicing them cleanly, leaving a furry, rough surface.
• Require significantly more downward pressure, tiring the turner’s muscles.
• Create heat and friction that can discolor the wood surface.
• Are more prone to catches, posing a safety hazard.
• Have rounded bevel edges that make it hard to control the cut.

Even small amounts of dullness can degrade the performance of turning tools and the quality of work. Most expert turners sharpen their tools frequently, sometimes before every project or even between cuts as needed.

Types of Lathe Tool Sharpening Systems

There are several options for sharpening lathe tools, each with their own pros and cons:

Bench Grinders

Bench grinders use a rotating abrasive wheel to grind away metal. Most have a coarse wheel for aggressive material removal and a finer wheel for honing an edge. Bench grinders are fast and effective for major reshaping of edges. However, controlling the angle precisely by hand can be difficult. A sharpening jig is often used to guide the tool.

Slow-Speed Grinders

Slow-speed grinders operate at under 500 RPM, much slower than regular bench grinders. The slower wheels allow cooler grinding to avoid overheating and losing temper on tool edges. Slow-speed grinders are easier to use freehand than fast grinders. Adding a sharpening jig improves angle consistency.

Belt Sanders

Belt sanders use a continuous abrasive belt to abrade metal. Models made specifically for tool sharpening often have variable speeds, adjustable tool rests, and a flat platen for honing. As with grinders, a jig helps maintain proper angles. Belt sanders remove material efficiently but require a delicate touch to avoid excess metal loss.

Whetstones

Whetstones, also called water stones, are blocks of abrasive material used to manually sharpen tools. Coarse-grit stones rapidly shape edges, while finer stones refine them to a polish. Whetstones are inexpensive and have a gentle sharpening action. However, they require developing consistent sharpening technique through practice.

Diamond Plates

Diamond plates use a diamond abrasive matrix bonded to a metal substrate to sharpen. Diamond plates cut fast, stay flat, and last a long time. They are more expensive than whetstones but easier to use. Diamond plates make quick work of reshaping damaged edges.

Tormek Systems

Tormek machines use a rotating water-cooled stone to sharpen, paired with jigs for gouges and other specialty turning tools. The water keeps the edge cool while sharpening. Tormek systems sharpen with precision but have a higher cost than other options.

Key Factors in Choosing a Lathe Tool Sharpener

Consider the following criteria when selecting a sharpening method for lathe tools:

Speed

How quickly must the edges be sharpened? Grinders and diamond plates work fastest for major reshaping. Whetstones take more time but can create a fine polished edge.

Accuracy

Is it critical to maintain exact bevel angles every time? A Tormek or well-jigged grinder offers the most angle precision. Freehand methods take practice to master consistent results.

Coolness

Does the edge need to stay cool to preserve temper? Slow-speed grinders and water-cooled stones such as Tormek limit heat buildup. Friction from high-speed grinders can burn edges if caution is not used.

Aggressiveness

Is the goal to remove material quickly or refine the edge gently? Grinders aggressively shape. Whetstones have a delicate touch better for finish sharpening.

Cost

What is the budget? Whetstones, diamond plates and slow-speed grinders are economical. Tormek systems and high-end grinders have more upfront cost.

Learning Curve

Are quick, easy results needed, or is there time to develop skill? User-friendly jigs and guides speed the learning curve. Freehand whetstone sharpening requires practice.

Portability

Does the sharpener need to move locations? Small whetstones offer portability. Bench grinders and Tormek systems are permanent shop fixtures.

Recommended Sharpening Systems for Lathe Tools

Given the variety of options, here are some recommended systems based on budget and needs:

System	Cost	Best For
Whetstone	$-$$	Inexpensive introduction to sharpening
Diamond Plate	$$	Faster sharpening with less learning curve
Slow-Speed Grinder	$$	Cool grinding for edge preservation
Bench Grinder with Jig	$$-$$$	Quick reshaping of damaged edges
Tormek System	$$$$	Precision sharpening for perfect bevel angles

For occasional turners, a basic whetstone or diamond plate sharpener can maintain edges at low cost. Those wanting to easily reshape edges after hits choose a bench grinder. Turners doing precision work who need perfect angles invest in a Tormek system. There is no universally “best” system – choose based on individual turning requirements.

Using a Bench Grinder to Sharpen Lathe Tools

A bench grinder with a sharpening jig is a common and effective sharpening solution. Here are tips for getting the best results:

Choose the Right Wheels

A 36-46 grit aluminum oxide wheel cuts metal quickly when shaping an edge. A 120-180 grit wheel refines the edge. White aluminum oxide wheels stay sharp longer than grey wheels.

Adjust Tool Rests

Set tool rests close to wheels so just the edge contacts the abrasive. Rests that are too low overheat edges and round over bevels.

Use a Sharpening Jig

A jig with angles matched to turning tool profiles ensures correct bevels every time. Popular options are the Wolverine or Varigrind jigs.

Grind Evenly

Use smooth, consistent motions. Grinding too aggressively in one spot creates an uneven edge. Let the wheel do the work.

Cool Between Grinding

Dip edges in water to cool metal and avoid losing temper. Quenching also washes away debris.

Finish on a Honing Wheel

Refine the edge on a 180-220 grit wheel to remove any burrs or distortions from coarse grinding.

Repeat Angles Precisely

Locking jigs in place ensures every tool has the exact same bevel angle and shape.

Maintaining Proper Angles is Key

The two most important angles on a turning tool are the bevel angle and the edge angle:

• The bevel is the angled surface right behind the cutting edge.
• The edge angle forms the sharp cutting edge where the bevels meet.

Typical bevel angles range from 20-40 degrees based on the tool. Edge angles are often in the 30 degree range. Consult recommended angles for specific gouges and chisels. Sharpening jigs are preset to hold these angles accurately.

If the bevel angle is too narrow, the edge will be weak and fold over. Too wide of a bevel increases wedging action. Uneven edge angles cause the tool to cut deeper on one side. Maintaining proper angles every time ensures tools cut cleanly and smoothly.

Sharpening is a Learned Skill

Whatever system is used, sharpening turning tools takes practice. Be patient, as it takes time to develop muscle memory and sharpening intuition. Use a permanent marker to blacken edges, making it easier to see where metal is being removed. Study the edge to ensure grinding is even across the bevel.

Initially expect to spend 10-20 minutes per gouge; with experience this time decreases dramatically. The more tools are sharpened, the better the feel for angles and pressure becomes. In time, quality sharp edges can be produced quickly and consistently.

When to Sharpen Lathe Tools

As a general rule, turners should sharpen tools:

• Before each use – fresh edges work best
• Whenever edges seem even slightly dull
• After any catches, hits, or banging of edges
• When tools require increased pressure to cut
• When surfaces show tearing, ripples or other irregularities

Many expert turners advocate frequent sharpening, sometimes every 15-30 minutes of turning. This prevents any degradation of edges and maintains them in optimum condition. Plan on sharpening as a regular part of the woodturning process.

Signs That Lathe Tools Need Sharpening

Watch for these signs that it’s time to sharpen a lathe tool:

• The tool requires extra downward pressure to make it cut.
• Shavings become powdery dust instead of long ribbons.
• The wood surface appears fuzzy, rough or burned.
• Cuts seem to skid and slide across the wood.
• The edge visibly looks rounded over when viewed up close.
• Catching or vibration occurs during cutting.

Even a great turner struggles to produce good results with dull tools. Don’t try to force a dull edge to cut. Stop and sharpen for productivity and safety.

Quick Field Sharpening Options

For quick touch ups, turners have additional sharpening options besides a full grinding station:

Diamond Pocket Hones

Small credit card diamond plates can hone an edge in a few strokes. These fit in a pocket for portability.

Leather Strops

Stropping an edge on leather charged with polishing compound can refine sharpness. A strop restores the “wire edge” that gets folded over from grinding.

Sandpaper

Wrapping sandpaper around a block makes an impromptu sharpening tool. Start with 220 grit to shape, then refine with 400+ grit.

Slipstones

These thin rectangular stones sharpen with just a few passes. Some designs have multiple grits for shaping and polishing.

A full grinding system most effectively sharpens damaged edges. But for a quick touch up, these field methods extend sharpness between major sharpenings.

Get the Most From Your Lathe Tool Sharpening System

Follow these tips to maximize the effectiveness of any sharpening setup:

• Study and follow recommended bevel angles for each tool.
• Sharpen gently – don’t force edges against abrasives.
• Always grind the inside bevel of gouges first.
• Cool tools in water to avoid overheating edges.
• Hone to remove any burrs left by coarse grinding.
• Keep jigs locked tightly in place each use for consistency.
• Check for even grinding marks along the bevel.
• Make sure the wheel or stone is clean and unglazed.

With good technique, even basic sharpening systems can produce the sharp, smooth edges needed for clean cuts and professional results.

Conclusion

Having razor-sharp lathe tools is a fundamental key to successful woodturning. Dull tools make any turner struggle. There are many effective sharpening options, from basic whetstones to jigged bench grinders and precision Tormek machines. Choose a system that fits individual needs and budget.

Mastering woodturning sharpening takes practice, but is a highly useful skill. Establish a habit of frequently honing edges. Well-maintained sharp tools reduce fatigue, create smoother surfaces, and make woodturning more efficient, safe and enjoyable.