A simulation tool for the finger jointing of boards

Knowledge about how tree properties affect the final product is necessary to utilise each log and tree in the forestry production chain fully. So far, the Swedish Pine Stem Bank (SPSB) has been used extensively for sawing simulation, but not for simulation further down the production process. Hence, it is desirable to model the further processing of sawn timber using the SPSB. In this study, a simulation tool for cross cutting and finger jointing of boards has been developed and tested. The simulation program utilises the SPSB and the results from a sawmill simulation program to simulate a cross-cutting and finger-jointing process. The tool has been tested against an empirical material consisting of defect data from an industrial scanner, used at a producer of finger-jointed furniture products. To illustrate the potential use of the finger-jointing simulation program, two investigations have also been carried out. The first deals with comparing the recovery for finger jointing and cutting of solid boards for different products. The second investigation is an attempt to estimate the impact of process-related defects on the recovery of finger-jointed products. The results show that the simulation tool produces similar results as the real process, and the use of the SPSB provides adequate predictions of the real system’s behaviour. The first of the investigations shows that finger jointing generally has a better recovery than cutting of solid boards, but for short products, the latter might be a viable option. The second investigation suggests that process-related defects reduce recovery by up to 5% units in the finger-joint process studied. Thus, there is future potential for using the finger-jointing simulation tool to investigate production strategies and/or raw material selection in the forestry production chain.Godkänd; 2011; 20110616 (magfre)