Analysis of the most suitable fitting type for the assembly of knockdown panel furniture E. Burdurlu H.H. Ciritciog ˘lu K. Bakir M. Özdemir Abstract In this study, we analyzed the assembly process of the following fitting systems from the aspect of cost: eccentric, inserted bolt lock, T, screw-mounting, screw-in type, and bracket and strip fittings. These are the most preferred fittings in the assembly of knockdown (KD) panel furniture. The fitting system with the least cost was sought. The direct labor, direct material, and direct energy costs, which are called the visible cost elements, were studied in the comparison. The stopwatch work measurement method was used to determine the periods of time needed for assembly. From this, the amounts of the cost elements were calculated. At the end of the analysis, the best fitting systems were determined as follows: 1) the eccentric fitting system was best for labor costs; 2) the screw-in type fitting system was best for material costs; 3) the inserted bolt lock and T fitting systems were best for the energy used during the assembly process; and 4) the screw-in type fitting system was best for the total visible costs. It would be appropriate to use the screw-in type fitting system for cabinets with doors, if the least cost is important, and provided that the consumer in the target market considers it to be suitable. It would be appropriate to use the eccentric fitting system if aesthetics are important, protruding parts are not wanted on the cabinet surfaces, and if a higher capacity is desired in the unit time period for the assembly of the panel furniture. Furniture can be separated into two assembly types: 1) fixed; and 2) knockdown (KD), which means it can be dis- mantled and assembled. Glue or other permanent fastening systems are applied to the system elements at the connecting places of the furniture in the assembly of fixed furniture. It is impossible to separate the parts without damaging the furni- ture, because of the hardening of the glue and the permanent attachment of the elements. The furniture must be moved as a whole piece for all transports. In KD furniture, sometimes called “ready-to-assemble” furniture, the connections of the elements are made to each other by special fittings prepared for this purpose without using glue or other permanent fasten- ing systems. KD furniture can be dismantled and assembled and generally it is assembled where it will be used. The ele- ments can be separated and the furniture can be reassembled at a later time in case it has to be moved for any reason. This characteristic of KD furniture has the following advantages and disadvantages: 1. KD furniture needs a smaller size interim storage space because the furniture parts are packaged as a system and these packages can be stored one on top of the other. 2. KD furniture decreases the unit transport costs, since more furniture can be transported in the same volume for the rea- sons given above. 3. The risk of damage from hitting and dropping during trans- port is greater in fixed furniture systems, since they are trans- ported in large masses. This risk is a lot lower in KD furniture. 4. The KD system is more suitable for ease of transport for mov- ing furniture, especially for renters who may move frequently. 5. The KD system is more suitable for the “build it yourself” marketing logic. 6. Unlike fixed system furniture, the KD furniture system does not need special assembly lines and can be assembled on location with simpler tools. This simplifies the production line and is a factor in the reduction of costs. 7. Consumers can move the KD furniture more easily from the furniture store to their homes. What is more important, the The authors are, respectively, Associate Professor of Wood Prod- ucts Industrial Engineering and Wood Products Industrial Engi- neers, Hacettepe Univ., School of Vocational Technology, Dept. of Wood Products Industrial Engineering, Beytepe, Ankara, Turkey (burdurlu@hacettepe.edu.tr; ciritci@hacettepe.edu.tr; kvncb@ yahoo.com; mustafa_ozdmr@yahoo.com). This paper was received for publication in July 2004. Article No. 9912. ©Forest Products Society 2006. Forest Prod. J. 56(1):46-52. 46 JANUARY 2006