In carpentry, a wide range of tools for various purposes is used. If professional carvers mainly use electric saws, knives and jigsaws, then household appliances are more likely to demand hand-held devices, which include a chisel. It is affordable and easy to use, but requires regular maintenance. Convenience and accuracy of wood processing will depend on the quality of sharpening the chisels. There are various ways to restore the sharpness of the incisor, the most effective of which will be discussed below.
Tools and consumables for sharpening
The simplest tool for dressing hand carvers is a grindstone. It can be used without special equipment, holding in hands and making reciprocating movements for mechanical impact on the target surface. In order not to injure your hands, you can wrap one side of the whetstone with a dense rag or make a sheath to hold it. The stone itself can have different characteristics. The main parameter of choice is granularity, i.e. the depth of the stitch.
A special tool for sharpening chisels in the form of a grinding device will help increase the productivity of the working operation. In a sense, this is a machine, but without an electric drive. Its design is designed to perform two tasks: gripping an abrasive bar (stone or file) and committing mechanical reciprocating movements on the bed. The work is performed by the user himself, but due to the guides and rigid fixation of the workpiece, the efficiency of processing the surface of the cutter is increased.
Sharpening Technique
Start work on the flat side of the knife. The correct grinding of this surface will be indicated by the presence of specular reflection on it. Regardless of the tool used, during editing the chisel should move back and forth along the abrasive. If the knife is fixed, then the stone or file will also be guided in a reciprocating manner. It is important to hold the working element with both hands and make movements smoothly along one trajectory without deviations. As for the force of pressure, it depends on how blunt the chisel is. Sharpening in carpentry workshops is usually carried out in several stages with abrasives of different fractions - they gradually move from coarse to fine grains up to the final refinement. After the operation is completed, dust, metal chips and other waste should be removed with a vacuum cleaner.
Editing at an angle and creating a chamfer
Exposure to a suitable angle when sharpening is one of the main conditions for obtaining a high-quality sharp cutter. The correct bevel geometry can only be determined on a grinder with a bed, which has already been mentioned above. On modern models, a scale is provided by which the angle of sharpening of a chisel on a tree is set - an average of 20 to 35 degrees. So, for an ordinary chisel, an angle of 25 degrees is suitable, and for a cleanser - 20.
The chamfer is located directly opposite the abrasive. Again, they often start with coarse-grained stones, but if the cutter is in a tolerant state and requires only light dressing, then you can initially use an abrasive of medium fraction. When making minor adjustments or cutting the top of the cutter, it is important to keep in mind that the surface of the stone itself can be deformed to a state of unsuitability for further work. This occurs when a small portion of the abrasive surface is used, which leads to the formation of a so-called grinding cavity. To eliminate the risk of the formation of such a defect, the technique of uniform work of the bar along the entire length of its surface will help.
Finish polishing
After the main correction of the chamfer, a responsible grinding step follows. It differs in that the blade acquires an optimal state in the part of the cutting edge. To solve this problem, use polishing devices like leather and felt abrasive wheels and belts. It is advisable to use an electric grinding machine as a power unit or carrier tool. There are compact household models that are equipped with grinding discs. In this format, the sharpening of the chisel is done with rubbing abrasive paste. In the course of work, the operator applies the mass several times to the blade and the working surface of the tape or circle. As an alternative to special grinding oils, experienced joiners suggest using soap solutions. However, the soap itself should not be made on an organic basis, otherwise the surface of the cutter and abrasive will become greasy.
Features of sharpening chisel knives?
In the equipment of planers, outwardly similar knives to a chisel blade are used. Moreover, in some models they can be almost identical in terms of cutter characteristics. But most often the planer is provided with thinner rounded knives, thanks to which, by the way, the carpenter can make a complex selection of wood pulp. Accordingly, an abrasive not so rough as a grindstone will be required - for example, many use emery of different fractions, as well as polishing devices. If we talk about the differences in the sharpening techniques of chisels and planers, then in the second case less effort is applied when the abrasive pressure is applied to the working surface. The operation itself is rather reminiscent of the process of finishing or finishing metal.
Conclusion
The nature of the implementation and overall organization of the procedures for servicing the chisel may vary depending on the nuances of its operation. It is one thing if the tool is rarely used and restoration of the blade is only required as a surface finish, and another is regular work with wood in the household. In the first case, the sharpening of the chisels can be done manually with grinding stones, and in the second case, more productive special units will be required. Before the homemaster, the question may arise of choosing the right equipment. According to experts, the optimal result is provided by a household grinding machine. The possibilities of equipping it with grinding wheels of varying degrees of grit and adjusting the speed of rotation allows you to cope with the sharpening of knives of chisels, planers and other cutting tools.