Wood chiselling involves cutting a thinner or thicker layer of wood with chisels, which, generally speaking, could be called wood knives. Long and narrow flat bar, from which the chisel was made, It is made of suitably hardened tool steel. The chisel blade must be very carefully formed and always kept in perfect condition. Therefore, under no circumstances should the chisel be used as a screwdriver, putty knife or chisel, because it is only suitable for wood processing, even a knotty one, however, it cannot withstand any other type of load, during which it chops or even breaks away completely. The chisel blade must be sharpened very carefully. First we sharpen them (only on the bevelled side) on a sandstone whetstone. Then the blade is polished on a marble moistened with water, to shine like a mirror. On the marble, we also gently polish the opposite one, the flat side of the chisel.
Due to the need to protect the chisel blades from damage, these tools should not be stored in a box with others. They should be hung on special holders in the tool cabinet.
When cutting thin layers of wood with a chisel, press the tool with both hands: hold the chisel in the right position with the left hand, with the right hand, we exert gentle pressure on the wooden handle. When cutting thicker layers of wood or when cutting it across the grain, hold the chisel with your left hand, and beat them with the right hand using a wooden hammer. The way of setting the chisel blade in relation to the processed surface is shown in the figure.
And here too, just like planing wood, the direction of the wood grain must be taken into account, to prevent uncontrolled splitting of the workpieces by a poorly guided chisel blade.
The figure shows how to make a rectangular hole in a wooden block. In the contour of the hole marked with a dashed line, first two holes of this diameter were made, so that their edges are as close as possible to the edge of the cut hole. Of course, in practice we will rarely deal with such a fortunate coincidence, that the contour of the hole to be cut contains exactly the full number of holes. It will mostly be like this, that there will be a smaller or larger gap between the holes. When making holes, put a chisel and cut the material a few millimeters deep along the line running across the grain. (1). And after that, gently and without hitting the chisel with a hammer, we start cutting the wood along the grain. Let's think about it, what would happen, if to take the reverse order? In most cases, such a change in the order in which the wood is cut would result in a crack (splitting) a whole piece of wood. If, after drilling, one of them was the so-called. blind, not cruising, we have to remove unnecessary wood located in the marked outline.
Finally, two practical tips. First, for correct and effortless chiselling, the tool must be razor sharp, a po drugie, easy and effective use of a chisel is possible only after acquiring appropriate practice and preparing the appropriate material for the construction, which should be dry, knotless and rather straight-grained. Naturally, this does not apply to wood-based materials.
One more note: we work with a chisel always "from ourselves". Working in the opposite direction, i.e.. "to each other", can cause dangerous injury.