One fact would always remain once you’ve decided to enter woodworking – you must learn how to sharpen your woodworking tools. Sharpening is a skill essential for woodworking, which you can only obtain successfully by practice and repetition. So, here’s a dedicated article for understanding the basic principles in sharpening a tool.
There are many ways of sharpening woodworking tools. It can be through the use of high grit sandpapers, a whetstone, or through the use of a grinding wheel. Regardless of the method, always maintain the shape and angle of the sharp edge of your tool. The main point in sharpening is to use abrasives in removing a part of the dull metal until you come up with a keen and sharp cutting edge.
Regardless of the kind of woodworking tools that you’re sharpening, the process should be comfortable in achieving the desired result. So, if you want to learn the basics of sharpening woodworking tools, you’ve come to the right place.
Understanding the Edge and the Abrasive
These are the two main components that play an essential role in sharpening woodworking tools. The edge refers to the area where two surfaces meet once you remove metal from one or both sides of the instrument. It is crucial to understand the various stages of the edge on its journey towards sharpness, and identifying once you’ve gotten enough.
Let’s give it an example for better understanding. Imagine sharpening a pencil. You have to check the tip of it when grinding to make sure that it is sharp, but remains durable. Otherwise, the graphite may fall off the body of the pencil when it loses too much skin.
On the other hand, an abrasive is any material that removes the metal. Usually, it has a rough surface called grit to be more productive. Some examples of abrasives include a stone, sandpaper, grinding wheel, or any honing compound.
How to Sharpen Woodworking Tools in 7 Steps?
Whatever or whichever abrasive you prefer to use, it should give you the desired result in sharpening your tools. Between sandpapers, a whetstone, and a grinding wheel – the most significant difference is the speed in delivering results. More about them in a while. In the meantime, here’s a simple step in sharpening woodworking tools.
- STEP 1: Evaluate Your Tool. Search and evaluate your woodworking tool. Understand the previous history of sharpening indicated by the horizontal strata running parallel to the edge. Then, identify the best abrasion to use at the correct angle. Once you’ve learned these concepts, it becomes easier to shape your tools.
- STEP 2: Square the Edge. Take note that this action is only significant if you have a damaged edge, wherein it needs to be ground away to expose the steel. To do it, use a square to mark a line using a felt tip marker across the back of the tool. It will serve as the base and indication where you should remove the metal. So, make sure that the line is below all damaged material. If it’s not a broken edge and you only need some resharpening, then jump to step 6.
- STEP 3: Remove any Scratches. The goal here is to polish the edge and make it look like its new. It requires a more excellent abrasive to remove all scratches, and it also involves direct downward pressure.
- STEP 4: Flatten the Back. This step is easy as there’s only one straight angle at the back of most woodworking tools. See and check if there are any scratches or other residues from the previous steps. Start with laying the end of your device on your abrasive material, maintain downward pressure, and make contact by moving it back and forth. You can use water or oil to make the process smoother. Stop until you see the back shines evenly across.
- STEP 5: Establish Bevel Angle. Flip to the other side of your tool and work on its bevel angle. This step requires your full attention because it involves rough shaping, which calls for fast metal removal. Remember that consistency is more important in this step. Don’t worry if you have an ugly angle. It is not your final. You only had to reduce the edge into a thin line to be consistent in thickness across the width.
- STEP 6: Refine the Edge. It is the transition between rough and smooth work. This step differentiates sharpening from honing. From the first step until sixth is fundamentally about maintaining the sharpness of the edge. It is step 6 for those who have a broken tip, but level 1 for a non-damaged tool with an available bevel angle. It is where you apply the finishing touches to your final edge, and the back face using a higher quality abrasive.
- STEP 7: Strop. It is the final stage in polishing the edge of a blade. Use a stropping compound made from chromium-oxide to give your tool its last finishing look. Attach a piece of leather to a flat piece of wood, and apply the stropping mixture. Then, hold the angle against the leather and pull back for 40 to 50 passes. Flip the tool over and do the same on its back.
Sharpening a Tool Using Sandpaper
Using sandpaper in sharpening woodworking tools may let you raise your eyebrows. You might ask, ‘how can it produce a decent edge on your tool?‘ It may not be as accurate and the best option, but it is feasible. Also, using sandpaper to sharpen a tool is the cheapest. If done correctly, this is a method that you can consider along with oil stones and diamond stones. Sandpapers are easy to use and can produce the sharpest cutting edges.
- Characteristics. Sandpapers are from various materials consisting of different features. Some components are suitable for wood finishes but may not be the best option for creating a smooth finish on metal. Not all sandpapers are ideal for sharpening woodworking tools. They also tend to work and wear uniquely. Some can wear out quickly, while others can last for multiple jobs before losing their bite.
- Grit System. Sandpapers have a grit system rated for coarseness or fineness by their grit number. The higher number means finer grit, which equals to rougher sandpaper. Coarse sandpaper is for removing material faster, but it may leave deep scratches. On the other hand, fine sandpaper eliminates less material but produces a smoother surface. The rates of its grit system vary from 24 for heavy material removal to 2000 and beyond for the gentlest sandpapers.
|12, 16, 20||Super coarse|
|220, 240, 280, 320||Extra fine|
|400, 500, 600||Super fine|
|800, 1200 and finer||Extra fine|
- Types. As mentioned, sandpapers use different materials that give them their unique characteristics.
|Aluminum Oxide Sandpaper||It is synthetic sandpaper that usually comes in sheets. Aluminum Oxide is an excellent choice for sanding bare wood and metal for painted surfaces. It provides outstanding results when used on a power sander. However, it may require a higher grit rate for sharpening metal.|
|Ceramic Sandpaper||It also comes from synthetic material, which is usually reddish-brown. Ceramic Sandpapers are incredibly durable and hard, which makes it ideal to use with power sanders. They are more expensive compared to the first type, but it can last up to four to six times longer.|
|Garnet Sandpaper||It is natural sandpaper that offers a more elegant finish, but garnet wears quickly after a couple of uses. It features a reddish or golden brown color, and commonly comes in sheet form. They are inexpensive and perfect for lighter hand-sanding works. Also, Garnet Sandpaper has a hard abrasive with sharp edges that fracture during sanding. It helps in creating a robust cutting edge.|
|Silicon Carbide Sandpaper||It comes in blue-gray or black, which is also suitable for both wet and dry surfaces of metal, plastic, and fiberglass. The most significant feature of this type is that it has a waterproof backing. Wet-sanding helps in reducing clogs and extends the life of the sandpaper.|
- How to Use? Using sandpaper should be as easy as using other abrasives. You can use some oil, put the tool on the sandpaper, and start moving back and forth. As a rule of thumb, it’s always best to start with the most coarse paper. Then, move your way up to higher and finer grits. So for example, you can start with 80 to 100 grit, step-up to 150-grit, then 220.
- How Many Do You Need? It depends on how often do you sharpen your woodworking tools. Usually, most woodworkers suggest having at least three sandpapers with different grit ratings. The grit depends on the finish that you want to achieve.
- Advantages and Disadvantages of Sandpaper.
|Using sandpaper for sharpening tools is cheaper.||Using sandpaper is the slowest method of sharpening woodworking tools.|
|The use of sandpapers is convenient, simple, and very easy.||The sandpaper may be subject to wear quickly.|
|It may be expensive in the long run because you have to buy repetitively.|
Sharpening a Tool Using a Sharpening Stone / Whetstone
The term “whet” refers to “sharpen the blade.” Sharpening stones, whetstones, or water stones are for sharpening the edges of most tools made from steel. Whetstones have both natural quarried and human-made materials.
- Characteristics. They come in different sizes, materials, shapes, and compositions. Some are flat for working flat edges or shaped tools like wood carving or woodturning tools.
- Grit System. Whetstones are available in different grades, which refers to the grit rate of the abrasive particles in the stone. Numbers represent them wherein higher digits indicates a higher density, therefore, smaller particles. It leads to a more exceptional finish on the surface of the polished object. The grit size relates not only to the degree of smoothness it can offer. It also represents the shape of the abrasive particles, the hardness of the abrasive particles, and the chemical composition of the abrasive particles.
|GRIT SIZE||TYPICAL USE|
|#200||For removing chips from a damaged blade|
|#500||For sharpening a blunt edge|
|#1000||To smooth a rough to medium edge|
|#4000||To smooth a medium to a sharp edge|
|#8000||For further smoothing a sharp edge. Usually for the meat of fish cutting purposes.|
|#30000||Used for polishing an edge to a mirror-smooth finish|
- Types. There are various classifications of whetstones according to the material used during their production, and the country of origin. To give you an idea, here are some types and their characteristics. To know the right lubricant, determine whether the whetstone is oil stone, water stone, or diamond stone.
|Arkansas Whetstone||It requires the use of oil as a lubricant. You should avoid using it with water as it may lose its effectivity. Arkansas Whetstones are classic natural sharpening stones graded according to their hardness.|
|India Stones||It is from human-made abrasive aluminum oxide. The name “India” refers to the trade name for Norton’s Aluminum Oxide sharpening stones. They feature orange, tan, or brown texture that makes them stand-out from other kinds of whetstones.|
|Diamond Plate||It is a steel plate mounted on a plastic or a resin base, coated with diamond grit. It is an abrasive that can grind metal with greater accuracy. Diamond Plates can be for sharpening steel tools or for maintaining the flatness of human-made Waterstones. It comes in various plate sizes and grit grades. A coarser grit is for removing a more substantial amount of metal rapidly, while finer grit is for eliminating scratches finer grit to refining an edge.|
|Japanese Water Stone||It is traditionally for natural sharpening stones that use water as a lubricant. Take note that using oil on any water stone may reduce its effectiveness.|
|Man-Made Whetstone||This type has been widely popular due to the widespread use of high-quality, consistent particle size artificial stones. They have the same quality as natural stones with superior sharpening performance due to its properties.|
- How to Use? Using a whetstone is essential and almost the same as using sandpaper. The difference is that you have to make sure whether it’s an oil stone, water stone, or diamond stone. If it is an oil stone, you should avoid using water to maintain its efficiency in sharpening. On the other hand, water stone should use water as a lubricant most of the time. Finally, diamond stones are the best type that can deliver speedy and accurate results. You can use either water or oil as a lubricant, but they are the most expensive kind.
- How Many Do You Need? Whetstones, regardless of their kind, are more expensive than sandpapers. However, they are only costly with your initial purchase. You need at least three sharpening stones – grinding stone, a sharpening stone, and a honing stone to be sure. 120 to 600 Grinding grit stones are a course at for repairing a dull or chipped blade. Sharpening stones are 1000 to 3000 grit for initial sharpening. A honing stone is 4000 to 25000 grit for final touches, polishing, and refinement.
- Advantages and Disadvantages of Whetstones
|Whetstones last longer than sandpapers.||The price of whetstones is high, especially those that have high-quality.|
|Using whetstones are faster and more accurate.||With their various types and different manufacturers that sell at premium prices, it’s hard to distinguish those that are authentic to the fake ones.|
|Whetstones are durable and easy to use.||It requires time to master the proper use of whetstone.|
|They are incredibly adaptable and can sharpen almost any kind of blades.||You have to hold the blade at the correct angle to ensure accurate results.|
|Whetstones feature a coarse and fine side that determines the amount of sharpening at each pass.||Whetstones are so effective that you have to make sure that you’re every move is correct. Otherwise, you may have wasted the blade.|
Sharpening a Tool Using a Grinding Wheel
A grinding wheel features an abrasive compound used for various grinding or rough cutting. Grinding wheels have multiple profiles and cross-sections depending on the purpose. The process of making grinding wheels is intricate because the manufacturers have to ensure the spinning disc while making sure that the uniformity of the composition.
- Characteristics. Grinding wheels has a motor that powers the procedure, which is from the pressed coarse-particle aggregate. These particles are bound together by cementing matric to form a circular wheel shape. They can be from a solid steel or aluminum disc with particles bonded to the surface.
- Wheel Grade. Grinding wheels have two grading systems to consider. It determines how tightly the bond holds the abrasive, which represents by letter A to Z. Letter A being the softest and Z is the hardest. Wheel grades affect other considerations in grinding like the speed, coolant flow, feed rate, and grinding depth.
|A to H||Especially for softer structures|
|I to P||Intended for moderately hard structure|
|Q to Z||Used for hard structures.|
- Grit Size. Same as the other abrasives, grinding wheels also have grit sizes on its rough part. It has less grit size than whetstones, but higher than sandpapers. Grit size determines the average physical size of the abrasive grains in the wheel. Larger grain size cuts more freely and faster but leaves poor surface finish. On the other hand, ultra-fine grain sizes are ideal for precision finish work.
|10 to 24||Coarse|
|30 to 60||Medium-coarse|
|80 to 200||Fine|
|220 to 600||Very Fine|
- Types of Grinders
|Cylindrical Grinders||These are primarily for grinding cylindrical surfaces. It uses regular grinding wheels with the grinding face for greater accuracy. The grinding speed is the Diameter of the grinding wheel multiplied by Revolutions of the motor per minute.|
|Centerless Grinders||They feature a design that supports and feeds the work using two wheels and a work rest. The two wheels feature a large one for grinding, while the smaller kind is for regulating both wheels. The speed is controllable from 50 to 200 feet per minute. On the other hand, the work rest supports the material that you want to grind.|
|Tool and Cutter Grinders||It is for grinding machines with the help of a bench or a pedestal to operate the grinder. The device moves across the face of the wheel continually to avoid any excessive grinding in one spot.|
- Types of Grinding Wheels. Grinding wheels differ mostly on their appearance, the material used as an abrasive, and the kind of motor that it features.
|Cup Wheel||It is ideal for Tool and Cutter Grinders. It features a slim profile that has the advantage of producing flat surfaces on most tools.|
|Straight Wheel||It is the most common type of wheel, which are often for bench or pedestal kind of grinders. They are only for peripherals, which can produce a slightly concave surface.|
|Cylinder Wheel||It provides a long and wide surface without any center mounting support. They vary in size of up to 12 inches in width. Cylinder wheels are specially for vertical or horizontal spindle grinders.|
|Tapered Wheel||It is a straight wheel that tapers outward towards the center of the bike. This setup is stronger than consecutive wheels, plus it can accept higher lateral loads.|
|Straight Cup||This kind is an alternative to tool and cutter grinders, which features an additional radial grinding surface.|
|Dish Cup||It features a very shallow cup-style grinding wheel, which allows grinding in slots.|
|Saucer Wheel||It is a unique grinding wheel that is primarily for grinding milling cutters and twist drills. Also, it is beneficial in maintaining sawblades.|
|Diamond Wheel||It is a grinding wheel with industrial diamonds bonded to the periphery for grinding sturdy materials.|
- How to Use? Most new Grinding wheels use electricity to power up the machine. On the other hand, there are those kinds that rely on pedestals to rotate the wheel. Regardless, using grinding wheels requires 100% focus to eliminate all risks in using them. Following the procedure in sharpening woodworking tools, you have to always look out for your fingers to avoid any injury.
- How Many Do You Need? One good quality grinding wheel is efficient in getting you through sharpening any woodworking tools. However, take note that it may not be convenient and flexible as the first two kinds of abrasives.
- Advantages and Disadvantages of Grinding Wheel
|Grinding wheels can produce a high surface finish with greater accuracy.||Grinding machines are high in cost. Probably, the most expensive kind of abrasive.|
|Grinding wheels can work efficiently even on the hardest materials.||It requires better understanding, knowledge, and skills in sharpening to use it correctly.|
|Grinding machines require less applied pressure while obtaining highly accurate dimensions.||Some types of grinding machines are only capable of removing a small amount of material alone.|
|Grinding machines can work at high temperatures as well.||Using grinding machines may take more time depending on the required amount of work.|
|When it comes to abrasive particles, grinding machines have self-sharpened action.||Using grinding machines require intricate and careful work because one wrong contact may lead to damages.|
|Grinding machines last the longest between a whetstone and sandpapers.|
|Most of the time, a smooth surface is achievable using grinding machines.|
FREQUENTLY ASKED QUESTIONS
What Is the Best Angle to Sharpen a Wood Chisel?
The best angle to sharpen a wood chisel depends on how your tool looks. Usually, both standard bench and butt chisels should have at least a 25-degree perspective in sharpening. This angle may also be applicable for most work. On the other hand, the edge may last longer if you can add a 5-degree micro-bevel to make a 30° cutting angle.
What Is the Correct Grinding Angle for Sharpening a Plane Blade?
More often, the correct grinding angle for sharpening a plane blade is approximately 30 degrees. Just like for chisels, it is already sufficient for an excellent overall bevel angle for a plane blade. Lower edge means the sharper edge will be.
How Do I Know If My Planer Blade Is Dull?
First of all, you will know that you a dull plane blade if it is not sufficient enough to go through your material. Instead of removing a part of the wood, it just slides through or can’t finish a cut. Another way to tell if the cutting edge is in poor condition is by the noise it produces. A wood planer is much louder if it has dull blades.
There are various woodworking tools, but the sharpening process almost remains the same always. It’s about giving a dull blade a new cutting edge to be usable again. Sharpening may look simple, but it requires a better understanding and knowledge to do it effectively. It is a skill that you can successfully achieve through continuous practices and learning from your failures.
More importantly, learning how to read the line on the edge is crucial to understand the right angle. As you get more knowledge, you will be able to establish your sharpening system that will suit your needs. What you need to do is to remove metal quickly and polish it accurately.