The basic constructional parts creating skeletal elements are beam elements, rod elements and sporadically board elements. The connections of beam elements belong to the angular corner, semi-cross and flat cross group, while the connections of boards are mostly parallel joints. Among these constructions, there is also a certain regularity. The tables are designed as constructions for assembly and disassembly, while chairs in the vast majority constitute closed systems.
4.9.1 Constructions of Tables
The main components of tables are the worktop and frame, which consists of rails and table legs. A typical connection of the legs of a table with the rails is a single covered L-type mortise and tenon joint (Fig. 4.73).
It ensures high durability of the furniture piece; however, it restricts the freedom of transport, and in the event of large dimensional furniture, it forces the designers to seek alternative solutions. This kind of connection can be used in constructions of small sizes and a complex build, requiring special equipment or tools during assembly. Rails and legs of a table can also be connected using screws and special connectors. With such a solution, a furniture piece is suitable for packing into a cardboard box, increasing the use of transport means and reducing the risk of damages during transportation. Examples of inseparable and separable connection of rails with the legs using the connections are shown in Fig. 4.74.
Worktops of tables are made of carpentry boards, chipboards, MDF boards, as well as glued wooden boards. Wide external surfaces are finished with veneers, and narrow surfaces with veneers, edges or laminated boards made of wood and plastic. Worktop can be mounted to the frame using wooden dowels set in holes of the rails and board (Fig. 4.75). However, this is the least popular way and most sensitive to the accuracy of the machining. Other connection methods involve the use of additional strips fixed to the top board of the table and bolted to the rails with screws or bolts (Fig. 4.75b-d).
Fig. 4.74 Examples of connecting rails with legs using the following joints: a straight single mortise and tenon joints, b straight single mortise and tenon joints with a connector, c straight single mortise and tenon joints used for a rod element, d straight single mortise and tenon joints with a screw connector and e straight single mortise and tenon joints with a bolt connector