Applying of Pressing Technology to Forming Finger-Joint Profile for Wood Splicing

Vyatka State University, Department of Machinery and Wood Technology, Moskovskaya st., 36, Kirov, 610000, Russian Federation

^* Corresponding author: olga_ru@vyatsu.ru

Abstract

Splicing of wood lengthwise is widely used in the manufacture of various products. The basic method of forming the finger joint profile is milling. This method has a number of disadvantages: high cost of the milling tool, necessity of its periodic sharpening; high energy consumption of the milling process, design constraints on the geometric parameters and strength of fingers (tenons). An alternative to milling is a new way of forming such joints elements as mortise and tenons by pressing along the grain. This method allows obtaining mortises in the form of fairly accurate rectangular imprints on the ends of the blanks. The use of a punching tool instead of a cutting one avoids chips and reduces the cost of the aspiration system. Previously, rectangular tenons were used only for L-type box joints. The aim of the study is to prove the possibility of using the cold end pressing technology to form the mortises and tenons profile for end joining that meet regulatory requirements. A series of experiments on pressing the elements of joints profile in the form of multiple tenons has shown that the achieved accuracy and roughness meet the requirements for the manufacture of joints intended for lengthwise splicing. Assessment of the strength of the joints showed their compliance with the regulatory requirements. The conducted research confirms confirms the possibility of using the pressing technology to form the profile of the finger joint for wood splicing.