You’ve spent good money on many lathe tools, but they’re no longer as sharp. Bluntness will not only affect your work’s quality but can also lead to serious work injuries.
If you want to maintain your tools, our experts will show you the most convenient way on how to sharpen lathe tools.
How to Sharpen Lathe Tools
A lathe tool is rotated about an axis to perform several operations on a lathe. Some of these operations include cutting, knurling, chiseling, sanding, drilling, and turning.
Nothing dulls a tool faster than a piece of woodturning at a very high speed, which makes sharpening a critical process. The lathe tool’s design allows it to do most of the work, not just the bit.
Nevertheless, the tool bits need to be sharpened often to ensure they don’t round out and lose their edge. It is a straightforward woodturning process once you get the hang of it.
Reason Behind Your Lathe Tool's Decline in Sharpness
One major challenge of woodturning is tool wear and tear, which in turn makes sharpening very essential. Carbon steel is prone to rust, and your tools can lose their edge to rust.
Dents and scratches can also reduce tool sharpness. Storing your turning tools in the wrong conditions and places like a moist environment or cluster in a box can dull its sharpened tip.
With time, the spindle and bowl gouges with your skew chisel will get blunt. One reason for this is the type of wood being turned. Hardwood will have an impact on your implement faster than softwood. Another reason your lathe tool isn’t sharp is it continuously drops out of your hand, causing the cutting edge to chip away. Misusing your lathe tools and for purposes other than what it is made for is going to cause a decline in sharpness.
Steps in Sharpening Lathe Tools
You are more likely to taper your lathe tool if you know what step to take and what accessory to have handy. Our experts will show you how to sharpen lathe tools for wood, metal, or glass lathe.
1. Prepare Tools And Protective Equipment
Before you start the process of sharpening, you need to get your equipment ready. You do not want to make several trips back to the grinder. Some implements you will need include:
- Grinding wheel: Grinding wheels are very essential in the tool sharpening process. To taper your tools, you can opt for a 6 or 8 inch antique stone grinder or the modern bench grinder. A grinder is also handy for shaping your tool. People often confuse shaping with sharpening. Shaping a tool such as a bowl gouge or any gouge refers to changing or creating a new bevel, while sharpening is the act of restoring the cutting edge of a chisel or spindle so that it can cut the way it is supposed to.
- Grinding jig: A jig is a guide tailor-made for your tool bits. It holds them in position at the exact bevel angle to the grinding wheel. Accurate measurements are required to set up a jig. However, a set-up jig is a one-time thing that provides you with a ready and waiting guide for quick sharpening.
- Eye protection: You would need either eye goggles or a face shield to keep fillings or sparks from getting into your eyes.
- Rubber gloves: These are necessary when sharpening lathe chisels, spindles, etc. and in woodturning, as they would protect your hands from little or big grazing. They also help absorb the vibration of the machine.
- Wheel dresser: A grinding wheel needs dressing from time to time, and the multi-diamond T-bar works perfectly for most.
- Ear protection
- Loose clothing
- Lathe tool to be sharpened
- A dry cloth and a bowl of water
2. Test Sharpness
There are numerous ways to find out if your turning tool needs sharpening.
- Thumb test: We recommend you run your thumb across the edge and feel for a bur. Do not run your finger along the edge of a sharpened tool, as this may injure you.
- End grain test: To test for the sharpness of your skew and gouge, take a piece of softwood such as cedar and clamp it down on your workbench. Run the gouge down a corner of the end grain; if it cuts out shavings, this indicates a sharpness. No shavings show the tool is blunt.
- Light test: Hold your chisels and gouges under a bright light. If they reflect light, they are dull; if not, they are sharp.
- Paper test: This test is used chiefly for skews than bowl gouges. Hold a piece of paper to the edge. If a clean, straight cut is made, the tool isn’t dull. However, if the cut on the paper is rough, the tool needs sharpening.
3. Prepare Grinding Wheel
Tons of metal fillings and wood chippings collect in the bench grinder over time. This debris makes prepping the bench grinder a significant procedure before you start sharpening. It is best to use a diamond sharpening tool to prepare the grinder. Rub the outer ends to remove any particles and even them out. Also, make sure the bench grinder is bolted securely.
4. Grinding Angles
Different lathe tools cut at different angles. Therefore, you need to sharpen them at different angles. This detail is especially true with spindle gouges and bowl gouges, the worker’s skill, and type of turning.
The size of chips and shavings are dependent on these angles. The angles can range from 5 degrees to 30 degrees.
The following are lathe tools with their grinding angles:
- Roughing gouge: Grind to 45 degrees, but a 35-degree angle also works when handling softwood. It is best to work with a V-pocket but be careful. The tip of your tool is in contact directly above the centerline of the wheel.
- Bowl gouge: The angle variants for this are so many. Start with a 50-degree angle and 60-degree angle; progress to a 45 and 40-degree angle as your skill improves.
- Spindle gouge: This is used to make little hollow openings and bowl turnings on a spindle stock. It is also used in turning coves and beads on a spindle stock. Grind to 45 degrees or 35 degrees (with better tool control).
- Parting tool: Sometimes called a flat, this is used in parting the spindle stock. An excellent grinding angle for the parting tool is 45 degrees, while the perimeter should be maintained at 90. Make sure the tool is held square to the wheel.
- Diamond parting tool: Our experts found 45 degrees is fine for this.
5. Pushing The Tool in The Grinder
You are now familiar with the angles for sharpening your lathe tool, so you need to make the right contact to yield the perfect results. It is recommended that you place the tool in the tool rest before you proceed. Make sure the blade isn’t pressing against the wheel of the grinder. Anything off will cause a lot of vibrations that would cause you to lose control.
Once your bench grinder is set, hold the tool against the wheel of the bench grinder, making sure contact doesn’t exceed 10 seconds. Our team found that a few sparks are to be expected if the angles and contact are exact. Anything longer than 10 seconds would cause overheating.
Repeat a few more times and once the bit is sharp enough, cool it in a bowl of water. Dry the bit before turning over to the other side. Be sure not to grind one side more than the other.
You can also do this process manually. For this, a sanding stone of 1000 grit will be required. Hold the stone with one hand at 45 degrees, and with a little pressure, move your tool back and forth on the stone.
Using a Belt Sander
Seeing as slow-speed bench grinders are very expensive, you can opt for a belt sander. They are less expensive and also perfect if you need to sharpen and shape turning tools. If you are going with a belt sander, it requires a two-inch belt as a one-inch belt cannot grind evenly.
The grit options for it are numerous. These options ensure that chisels are honed to perfection. If you don’t intend to turn a lot of wood or metal, this is a great alternative. A huge plus is its versatility outside work with turning tools.
How often should you sharpen lathe tools?
You should sharpen your lathe tools as soon as they are dull. You could do this before you commence your work or just during routine maintenance. Ensure you are adequately covered up and have the right gear . When in doubt, touch it up.
What angle do you sharpen lathe tools?
You can sharpen your lathe tools at various angles but the most ideal would be 45 degrees. The slant depends on your level of control and the particular item being worked on. We recommend you hold the turning equipment lightly at an exact angle.
You can make your jig and handle your equipment’s maintenance at a price relatively lower than you would be sending it into a maintenance shop. This allows you the opportunity to improve your skill level and get very hands-on.
Our experts have shown you how to sharpen lathe tools. It is not as frustrating a task as one might initially think, but it requires some practice and guidance to perfect and get things done.