I once sharpened a couple of narrow chisels, they seemed sharp, they cut well, but the chamfer, which in theory should be flat, always turned out to be semicircular. These are, of course, all little things and don’t affect the quality of the work, especially if you don’t do wood carving and use chisels only occasionally, when you need to cut out grooves or recesses for hinges and locks. It’s easy to get rid of this joint with an electric sharpener, but with manual sharpening it’s somewhat tedious.
And when it came to a 4 cm wide chisel, I realized that I needed to make some kind of holder (corner). I didn’t want to bother too much with its design, since we use chisels once every five years and won’t have to sharpen them very often. At first I tried to make it on a hinge so that I could adjust the sharpening angle, but I quickly abandoned this idea, the design turned out to be shaky, and when you set the angle to less than 40°, the design begins to take up a lot of space.
In general, I assembled a monolithic corner from three pieces of chipboard, a couple of corners and several screws. The length of the main piece was determined using a chisel (so that the handle did not rest against the counter).
This piece (platform) is needed so that the handle of the chisel does not get in the way when tightening it with the plate.
We drill, countersink and screw the platform.
I screwed a plate from a window shutter as a clamp.
I placed the stand and marked the holes on it
Before screwing it into place, I sawed off the corners to make it easier to hold the corner when sharpening
Reinforced with two long self-tapping screws.
Tests showed a slight play when pressing hard on the corner, so metal corners It’s better to install it with a stiffening rib or cut out triangles from the same chipboard instead of iron corners. Better yet, just cut out a ready-made monolithic corner in the shape of the letter L from chipboard or plywood, thus getting rid of any joints in the corner, but this will be a completely different design. The dimensions were not particularly calculated, everything was assembled from pieces of chipboard, but just in case I drew the dimensions.
In this place (photo below), from the corner on which the corner stands, I cut off a couple of millimeters of the PVC edge, since during sharpening such a long contact area slowed down the corner very well, I left only three centimeters at the edges as legs, the best option it would be possible to screw the rollers around the edges, but this would complicate the already complex design. :-)
This is a very old homemade chisel on which I will check the corner, a little broken of course, but the piece of iron itself is good :-)
Everything is assembled and ready for sharpening.
I sharpened it on regular sandpaper in three passes, the lightest and the paste is for showing off, but more on that below :-)
Here I made a mistake that increased the working time several times; before sharpening, I slightly aligned the cutting edge with the Dremel so that it was smooth and not a semicircle, but as it turned out, the chisel had slight wear on the opposite side at the corners. This means that to get a straight edge I would have to chamfer 5-6 mm. I know that it’s supposed to be smooth, but I decided to make an exception for myself. :-)
This photo shows how easy it is to set the desired sharpening angle; I didn’t get too carried away with geometry, I simply placed two pieces of chipboard under the chamfer and thereby obtained the angle that this chisel had before sharpening.
The chamfer is brought to the plane.
The formation of a burr begins, the rounding of the corners of the edge is already visible due to the wear on top of the corners. I didn't dwell on it.
After the burr has appeared along the entire edge, we switch to paper with a finer grain, and then to the finest grain; the more steps, the less paper consumption.
I used this paper as a scratch paper, (it’s the same one at the top) and removed the remaining burr on it.
After zeroing you can already see the reflection almost like in a mirror :-)
And it cuts paper quite well, although with a little effort, and at the same time it must be moved from side to side, the movements are similar to how bread is usually cut.
In principle, this kind of sharpening is enough for me, but I still decided to try to bring it to planing hair. To show off, I used what was at hand, namely, paper with even finer crumbs and goyim paste.
I didn’t find a belt or a piece of leather, I just applied the paste to a sheet of paper and polished the chamfer on it.
The result was a mirror, the paper began to be cut a little easier, sometimes it is even unnecessary to move it from side to side, but simply feed it onto the blade. It doesn't cut hair well, it only cut off a few hairs, so you can say it doesn't cut hair at all. Most likely I'm sharpening incorrectly, but that doesn't matter, the thread is about a corner for sharpening flat pieces of iron, and everyone sharpens in their own way. :-)
Video fragment. Well, somehow, somehow, she cuts my paper. :-)
In general, I am satisfied with the corner, the geometry in the reflection does not break much, which means the corner does its job.
Every craftsman who works with wood has carpentry chisels in his arsenal. A wood chisel is very useful in work that involves processing wooden blanks. Perfectly sharpened blade various shapes used for carving of any complexity. IN construction stores can be bought as ready-made kits devices and chisels individually.
Chisels for carving. Classification
The chisel represents professional tool carpenter or joiner, used to prepare wooden blanks for further processing. It will help to chamfer and apply carving patterns by removing excess layers of wood. The design of the chisel is very simple - it has a plastic or wooden handle and a sharpened blade of various shapes.
The following types of chisels exist:
- a straight chisel is needed for processing wooden blanks and cutting simple recesses
- an oblique chisel has a blade that is beveled at an angle of 450. It is used for cutting longitudinal grooves, as well as work related to the primary processing of the workpiece
- an angular chisel is similar to the English letter V, 2 closed planes of the blade are at different angles. It is necessary to create V-shaped notches. The sharper and shallower the angle of the cutter, the deeper the cutter will get
- A semicircular chisel for wood is perhaps the most important type of this tool. With this semicircular tool, the product is prepared, and ornaments of varying complexity are cut out and serifs are applied. The semicircular chisel can be round, medium or sloping
- cranberry is very similar to a semicircular chisel. The main difference is that its working surface is rounded not only along the end of the blade, but also along the shaft. This shape guarantees a clearer movement of the tool on wood. Cranberries are different. Their cutting part can be rounded, angular or straight
- Caesars can also be called a type of semicircular chisel, but they have a narrower working part, only 3 mm in width. Their main purpose is to cut thin grooves and work out the most small parts ornament
- The gravers have a mushroom-shaped handle and an oblique cutter. They are mainly used for cutting grooves. With increasing pressure from the master, the carving becomes clearer and deeper
- A rivet is a mini wood chisel that has a thin sharpening of a narrow blade, similar to a sharp leaf. This tool is used when ordinary chisels cannot create a drawing of the required accuracy.
- The marigold is also a type of mini chisel. It is designed for cutting thin fragments, however, more rounded than rivets
- the reverse chisel, like the cranberry, has a recess convex outward to create a protruding pattern above the plane of the main canvas.
Almost all of the listed chisels can have various modifications. A flat chisel can be wide or narrow, an angular chisel can have a wide angle or a narrow one, round bend can be flattened or radial.
Choosing a chisel
Before choosing a chisel, you need to decide what kind of wood carving you will be doing. If you rarely use them, you can buy an inexpensive set that contains the basic models of the device. Most often, such kits are purchased, for example, for window repairs or other simple tasks.
However, if you are engaged in wood carving and plan to develop in this direction, then you should not save. You need to purchase the best quality tools. According to the manufacturing method, there are three types of models:
- forged. These chisels have the thickest blade, as a result of which they can easily interact with hardwood
- die-cut These devices are convenient for precise and accurate work with soft and medium grades of wood.
- stamped. When working with them, it is necessary to install a thrust washer so that the device does not deform when struck by the mallet.
Craftsmen consider the most convenient chisel length to be 10-15 cm. A longer tool can withstand less load. The handle can be made of wood or plastic. According to reviews, the plastic handle is more durable and better withstands impacts.
The quality of the chisel directly determines its period of operation, as well as the quality of the resulting product. The quality of the device depends on the quality of the hardening of the metal part. The best metals for chisels are tool metals that are characterized by high strength and a longer service life. Tool steel is designated by the following markings:
- drop forged
- inscription "chrome vanadium"
It is worth paying attention that the manufacturer is marked on the label. If this information is not available, and the price of the set is quite low, then you have it in your hands Chinese fake.
If the type of steel is not marked, you can check its actual quality on a sharpening stone. On properly hardened steel, when sharpened, burrs form, which are easy to remove. If no burrs form, it means the steel has been overheated and the tool is dangerous. If burrs form, but cannot be removed, it means that the steel is too soft and will not withstand sharpening, and the sharpened edge will be subject to deformation even with little force.
Main wood carving techniques
Different carving techniques require different positions of the device in relation to the wooden plane. There are three main ways to work on wood with a chisel:
- pruning This work is carried out on the growth of fibers; The tool is positioned with the unsharpened side of the blade facing up, while you need to hold the handle with one hand and the blade with the other so that thumb was aimed at the handle. If you hold the chisel in this position, the master can easily set precise forces to obtain the most even and smooth surface possible
- side cutting or selecting grooves. Flat chisels are used to obtain rectangular grooves. The sharp edge can be beveled or straight. Most often, such a chisel is sharpened only on one side. Options with a semicircular sharp edge (in the form of a quarter or semicircle) of the canvas are used to create grooves in a circular manner
- perpendicular cutting. In this type of work, the chisel must be held by the handle with one hand, and the blade should be held with the thumb and forefinger of the other hand. In this way, you can thinly cut wood chips once. Note that this method is the most labor-intensive.
Wood carving chisels are not designed to cut large amounts of wood at one time. Their task is to remove excess wood gradually, adhering to pre-defined lines.
You can use a mallet or hammer during the cutting process. These additional tools will be needed if you need to quickly make a recess or hole. At the same time, complex patterns require a lot of work and are cut out slowly.
Universal chisel
Just a few years ago, work with wood was carried out using hand tools, however, today there are devices, for example, an electric chisel, which make it possible to significantly facilitate the work of the master, as well as increase the speed of work while maintaining high quality.
An electric chisel is called universal because it allows you to carry out a wide range of work. High power chisel models can handle removing old parquet board or carry out rough processing of large wooden blank, remove knots and other hard inclusions. It is impossible to cope with such work using only hand tools.
This tool is considered universal because it has many attachments. different forms and sizes. For example, small semicircular and straight 4 mm bits will help you make patterned carvings or engrave the master’s initials, while more massive tools, up to 5 cm wide, are designed for removing wide chips and roughing.
As is known, sharp blade safer than stupid. This statement is also true for a chisel. An important point is to clean the sharp edge of the chisel once or twice a year, depending on how often you use the tool.
Even brand new chisels may not be sharp enough to carry out complex woodworking, for this reason it is worth sharpening them before the first use.
If old chisels have uneven or damaged bevels, they can be corrected using grinding wheel. It is necessary to hold damaged chisel bevels against the grinding wheel to remove serious burrs, dirt and rust.
The stone should have three levels - beginner, medium and fine. It is this stone that will allow you to achieve the most acute condition. Sharpening stones are sold at gardening and hardware stores. The stone is sold with lubricant; if it is not included, the seller will recommend purchasing it separately. The most effective types of stones are:
- water stones. For such stones as lubricant use ordinary water. They need to be soaked in water for a few minutes before using. This type of stone is very popular in Japan
- Oil stones should be lubricated with petroleum-based oil before use.
Sharpening the chisel should begin with the flat side. The flat edge has a mirror image after proper sharpening. You need to move the chisel back and forth along the stone chips. Hold it with both hands, make smooth and progressive movements, without jerking. If scratches appear on the flat surface of the stone, work must be continued on a medium-grain stone, and then on a fine one. The flat side of the chisel will be fully sharpened when it has a mirror image.
Sharpening a bevel using a stone is quite difficult. Better to use special device. It is necessary to place the chisel in the sharpening device and tighten the screws to secure it tightly. Depending on the type of chisel, it is necessary to set the device to form an angle from approximately 20 to 35 degrees:
- cleaning chisel - 20 degree angle
- an ordinary chisel - an angle of 25 degrees.
Place the bevel against a coarse-grained stone. Hold it with both hands. Move the chisel back and forth across the thin stone, as if taut. If scratches appear on the bevel, continue working on a medium-grain stone, and then on a fine one. When changing stones, you should wipe the blade.
Proper sharpening of the chisel ensures precise cutting and ease of control of the tool. However, not only the sharpness of its blade is important, but also the sharpening angles, which depend on the type of tool and the characteristics of the work performed. If sharpened correctly cutting surface and maintain the appropriate chamfer angle, the carpenter will make much less effort when removing chips and can easily maintain its thickness. And this directly affects not only the cutting accuracy, but also labor productivity.
You can sharpen and finish the cutting part of the chisel using both manual and powered abrasive tools. Typically these are various sharpening stones wrapped sandpaper bars, sheet abrasives, polishing bases made of fabric and felt, as well as vertical and horizontal sharpening machines. In order to sharpen a chisel, you first need to fix it at the desired angle to the abrasive plane. Many people do this manually, which, with certain skills, provides more or less acceptable quality. However, most craftsmen sharpen chisels using special devices, fixing their blades strictly at a given angle.
The chisel is manual carpentry tool, consisting of a handle and a blade, which in everyday life is also called a blade (see figure below). Its metal part is made of tool steel, and the handle is made of hardwood: oak, beech, hornbeam, birch, acacia. Recently, modern materials have also been used as a material for handles. polymer materials. Wood is cut using a chamfer cutting edge, the sharpening angle of which depends on the type and purpose of the chisel.
Sharpening a chisel yourself is not difficult if you follow certain rules. Regardless of what and how you assemble it (manually or using an electric sharpener), its blade must be rigidly fixed at a given angle, not only in the longitudinal direction, but also in the transverse direction. Inclinations of the chamfer to the right or to the left are unacceptable, as this causes the tool to drift and uneven chip removal.
The chamfer can be sharpened using a grinding stone with a grain size of 300÷400 microns. The main thing is to achieve its linearity and equality of angles of inclination on both sides of the canvas. Finishing and sharpening cutting edge produced on a grinding stone with a grain size of 50÷80 microns.
The inclination of the chisel blade chamfer depends on the type of work for which it is intended. Typically its value lies in the range of 25±5º. This value is standardized by GOST 1184-80, but in practice it may differ slightly in one direction or another. Typically, the angle at which a chisel blade needs to be sharpened is directly related to its thickness: thicker blades tend to have a steeper bevel.
To perform slotting work using a mallet, the chamfer must be sharpened at an angle of 27÷30º. The steeper angle prevents damage to the cutting edge when significant impact forces are applied to the chisel. If you have the only chisel at home, it is better to sharpen it with a bevel of about 25º - this is suitable for most carpentry work. But for accurate trimming and removal of thin chips, the tool will have to be sharpened to 20÷22º. The bevel of the cutting edge relative to the chamfer plane is usually about 5º.
Sharpening accessories
A standard chisel sharpening kit includes three main components: an abrasive for initial processing, abrasives for finishing, and a sharpening mandrel for fixing the angle at which the blade needs to be sharpened. The latter is divided into two types: equipment, with which the cutting edge can be sharpened on an abrasive wheel of an electric sharpener, and manual mandrels for grinding on bars and sheet abrasives.
Manual devices have many options: from homemade wooden devices, in which the angle is set using wedges, to factory-made metal products with angular adjustment. All of them are designed approximately the same and consist of two main functional components: a carriage for moving along the abrasive surface and an inclined platform with a clamp, which is set at the required angle before sharpening the blade. In order to sharpen a chamfer, use both hand tools, and a power tool, but the finishing of the cutting edge is done only by hand.
Using a wheel and sandpaper
When forming a chisel chamfer, various sharpening stones are used: both round ones on an electric sharpener, and flat ones in the form of sharpening and grinding stones, as well as sheet sanding material on fabric and paper based. To sharpen the bevel of a chisel on, you need to make sure that its speed and the one installed on it grinding wheel will not cause overheating and release of the metal chisel. The rotation speed of the spindle of the electric sharpener should not be higher than 1800÷2000 rpm, but a viscous, medium-soft one with a grinding filler (for example, aluminum oxide) should be used.
In order to sharpen and polish a chisel blade efficiently, it is necessary to use abrasive products that combine both grinding and polishing qualities. Sharpening water stones are best suited for this role. Before starting work, they must be soaked in water, which rises to the surface during sharpening, mixes with abrasive dust and creates a viscous grinding suspension. Fine-grained sheet abrasive material is also well suited for such work. During the sharpening process, it must be wetted, so it is advisable to use waterproof sandpaper. You can sharpen the chamfer and edge of a chisel using this material by fixing it on a flat surface or wrapping it around a wooden block.
Imprisoned under the right angle chamfer, you can proceed to the finishing operation, during which the cutting edge will be brought to extreme sharpness, with work surface all micro-irregularities and scratches will be removed, and the surface itself will be polished to mirror shine. IN in this case grinding is a consequence of finishing, since the main goal at this stage is the linear accuracy of the working surfaces.
Finishing and grinding are inherently different operations. The first provides geometric accuracy the plane of the chamfer, and the second is the class of its roughness. Perfect mirror surface may be tilted to the left or right or have a significant convexity, which will lead it to the side when moving the chisel.
There are two ways to sharpen the cutting edge at the finishing stage. Either simply bring the working end of the chamfer to the required sharpness, or form a slight bevel several millimeters wide with an inclination to the chamfer of approximately 5º. To do this, first the main plane is adjusted, then the sharpening mandrel is set at an angle of 30º, after which grinding continues until the specified bevel width is achieved.
The process of sharpening a chisel with your own hands
To sharpen the cutting edge of a chisel with your own hands, you need a strong grip, attentiveness and patience, as well as a minimum set of sharpening and grinding materials. If you need to significantly change the sharpening angle, it is better to first use sharpening machine. If there is no such need, then you can sharpen your chisel in the following order:
- Grind the chamfer using an abrasive stone until there are no visible holes or damage. It is necessary to strictly maintain its inclination not only in the longitudinal, but also in the transverse direction. This can be done either manually or using a homemade clamping device from several wooden blocks.
- Check the line of the cutting edge, which should be strictly perpendicular to the chisel blade. If not, straighten it with a sharpening stone and then re-sharpen it to a sharp point.
- Wrap wooden block fine-grained sanding paper, secure it with nails or staples, moisten it with water, and then, carefully pressing the chamfer to the abrasive surface, sand it to a shine and an extremely sharp edge. If desired, the blade can then be polished on a felt wheel using polishing paste.
- If you need to sharpen a chisel with a bevel on the edge, then grinding is best done with a stop, lifting the blade up by about 5º.
- After finishing work, carefully wipe the chisel dry.
To properly sharpen a chisel, you need to remember one important thing: technical rule performing grinding and sharpening work: all movements should be performed in one direction only.
In Russian-language articles, authors almost never focus on sharpening the bevel of the cutting edge. In practice, many people actually do without this option and use straight edge chisels. What do you think about this? What's the best way to sharpen a chisel? Please share your thoughts and experiences in the comments to this article.
It is impossible to imagine a modern carpenter without a set of chisels. And, although this woodworking tool is of German origin, our compatriots made a huge contribution to improving the standard sizes of chisels for wood carving.
Why do you need a chisel?
This tool can do a lot. IN in experienced hands Using a chisel you can:
- select an unnecessary amount of wood, and in hard to reach places;
- align the edges wooden furniture;
- obtain roundings with any radii;
- create a whole composition from a shapeless piece of wood (here, however, you will need a certain set of chisels).
There is a common belief that chisels are exclusively woodworking tools, but this is not true. Certainly sharpened chisels can work on soft metal (aluminum and even mild steel), leather and plastic.
The functions of a chisel are similar to the work performed with a chisel, the difference is only in the volume of wood removed: with a chisel they are smaller, since the cutting edge itself is narrower than that of a chisel. The angle of the cutting edge is also different.
Chisels are used in the manufacture of wooden objects (carpentry chisels), for artistic carving for wood (artistic cutting chisels), for processing wood on lathe(machine chisels).
Such a wide variety of carpentry operations is given to the wood carving chisel by the shape of the working part of the tool. She may be:
- Straight - to obtain smooth edges along the entire length of the workpiece.
- Oblique - for making narrow grooves and obtaining corner edges.
- Semicircular and round - for shaping radius curves or spherical fragments. Sometimes such chisels are called chisels.
- Angular, which is used to design blind holes of non-round cross section.
- Curved, designed for working with undercuts and spherical surfaces (such chisels are called cranberries).
The opposite, attachment part of the chisel - the shank - is a forged conical rod that is driven into a wooden handle, after which it is fixed in it using a special ring - it is necessary so that when struck, the tool blade does not come out of the handle.
Chisel blade for carving good quality made from tool steels type 8ХФ or 13Х. The peculiarity of the metal is the presence of a fairly high percentage of carbon (at least 0.7...0.8%), as well as the obligatory presence of chromium, and sometimes tungsten. The hardness of the chisel should not be lower than HRC 59...60: otherwise, you are looking at an ordinary Chinese fake made of 45X type structural steel, which will have to be sharpened every time.
For ease of work, it is worth purchasing a set of chisels. Sets from brands Sandwik, Narex, Bahco (among the domestic ones, chisels from Enkor are listed, but under one condition - if they are made in Russia and not in China).
Technique for working with a chisel
In addition to a chisel, for wood carving you need a mallet - wooden hammer, with blows on the back of the handle, shaping occurs. You can use chisels on soft wood without a mallet.
Basic operations of thread shaping, which are performed using chisels:
- Trimming edges. It is carried out only along the fibers, and consists of forcefully moving a straight chisel with the unsharpened part of the blade upward.
- Side cutting and groove cutting. Here, oblique, angular or semicircular chisels are used - the type of blade is determined by the configuration of the edge. Blade sharpening is predominantly one-sided, and the quality of processing depends on the angle of sharpening: a flatter blade processes wood better, although the removal of chips in this case is less.
- Cutting fibers in the transverse direction. It is done with a chisel of any type, but with a freshly sharpened blade, otherwise tearouts of the material and the formation of burrs are possible. The most labor-intensive technology, since the effort required is the greatest, and the waste removal per pass is the least.
- Carving near knots. Curly chisels are used here, mostly round and semicircular. A tool of this type ensures a more gradual penetration of the blade into the workpiece, which reduces the possibility of defects during operation. The same chisels are also used for cutting grooves.
- Cleaning the semi-finished product from wood residues. If such work is to be performed in deep, semi-closed cavities, then cranberry should be used. The curved working part of such a chisel provides access to the most difficult parts treated surface.
- Removing material on the machine. When carving, this technology is used less frequently, mainly for pre-processing. For hard wood (oak, pear, walnut), the spindle speed is reduced, and the chisel used should have a flatter blade.
It should be noted that for the success of the operation, not only the type of chisel is important, but also the width of its working blade. When carving wood, it is recommended to use a narrower tool, which provides increased precision.
Choosing chisels for carving
We have already talked about the metal of the blade. The steel grade is indicated electrographically on the chisel itself. For imported products, the labeling must contain symbols elements – W, Cr, Cr+W, W+Cr+V. Some manufacturers will indicate the product and the grade of steel itself, for example, 62SiMnCr4, 80CrV2 or 86CrMoV7. Labels like “hardened steel” should not be taken seriously.
Important has a technology for obtaining a shank. It must be forged, with corresponding metal flow lines. Forging gives the steel a fine-grained structure and contributes to a more uniform distribution of hardness along the length of the chisel. Otherwise, at the transition point from the blade to the shank, a zone of stress concentration is formed, which, given the impact nature of the load applied, will eventually manifest itself in the form of surface cracks. In addition, in forged shanks, the metal fibers are not cut, which gives the nozzle part increased elasticity. Instructions about forging on foreign-made chisels are provided in the form of an explanatory inscription “drop forged”. If such an inscription is missing, the shank was most likely milled, and its durability will be significantly less.
The quality of heat treatment of a wood carving chisel can be easily determined by the nature of the burrs formed when sharpening the tool on a whetstone. If the burrs are easily removed because they stick to the surface only due to magnetization forces, then the chisel is hardened correctly.
The next choice is the blade length. It should not be less than 130...150 mm, but it is also undesirable to purchase chisels with an increased length - their longitudinal resistance is reduced, and a long tool is not always practical for delicate woodwork.
Wood is more suitable for the handle material: it is “warmer” and better withstands shock loads, absorbing the bulk of vibrations. On the other hand, plastic is durable, so the final choice will be determined by the complexity and frequency of the operations performed.
