The interaction of a circular knife with wood is a simple but interesting topic. The article will analyze the interaction of a knife with wood. A program is described that allows determining the preliminary deformation force for various disk shapes: rings, prisms, spheres, according to a given penetration area. Two periods of pressing are considered, both continuous and hollow, with sharply different pressure changes. Talk about the process of deformation of wood during compression along the fibers. Conclusions are drawn to reduce the cutting force. To establish the relationship between the degree of pressing and the axial stress (division force), a series of experiments were carried out on a testing machine using standard samples of pine and poplar wood. An experimental curve is constructed in a system of rectangular coordinates. With the help of a mechanical dynamometer, the total force of the division of softwood was determined. Theoretical substantiation of the obtained force of cutting with a disk knife is carried out. It has been established that the total effort of cutting soft wood is on average less than when sawing with round saws by 20-30%. It was also found that the smallest contact spot of the cutting disc with wood up to a contact angle with wood of 90 ° changes insignificantly and the total cutting force decreases with a decrease in the contact angle.

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The article pays special attention to the technological process of woodworking. The work examines all stages of wood processing, emphasizes the features of each stage. In this article, we try to say that all processing steps are important in production and represent a complex system of interactions.

The paper discusses the classification, structure and properties of natural phenolic compounds found in conifers wood species of Russia. The reasons for the variety of detected phenolic compounds (more than 2000) are considered, including the type and conditions of plant growth, environmental factors, as well as methods for extraction of substances. Coniferous extractives include monomeric, dimeric and polymeric phenolic compounds in bound and free form, and their content differs significantly for various species and parts of a woody plant. Depending on the polarity of the solvent used (water, petroleum ether, dimethyl ether, ethyl acetate, acetone, etc.), the yield, chemical composition and structure of the extracted phenolic compound change. It was shown that bark extracts of Larch and Fir contain the most phenolic acids and extractive substances than Pine, Cedar and Spruce, while the content of polar substances is higher in needles, and non- polar substances in plant shoots. Phenolic compounds are secondary plant metabolites, exhibiting fungicidal, virucidal and strong antioxidant effects, that make them a valuable basis for the creation of drugs.