Journal of Applied Polymer Science, Vol.103, No.3, 1664-1669, 2007
Effect of PVAc bonding on finger-joint strength of steamed and unsteamed beech wood (Fagus sylvatica)
Beech wood is one of the most important species used in furniture production in Europe. In this work, the effects of poly(vinyl acetate) (PVAc) bonding [durability classes D1, D2, and D3 according to EN 204 : 2001), finger length (4 and 10 mm), and finger orientation on the bending strength of finger-jointed steamed and unsteamed beech wood (Fagus sylvatica) were studied. Specimens were prepared according to EN 385 (2001) and modulus of rupture (MOR) and modulus of elasticity (MOE) tests were performed according to the procedures detailed in the ISO 10983 (1999) and DIN 52186 (1978) standards. The MOR of unsteamed wood joints ranged from 33.51 to 82.24 N/mm(2), whereas the MOR of the steamed wood joints fluctuated from 34.9 to 80.27 N/mm(2). In both steamed and unsteamed wood the specimens with a finger length of 10 mm showed higher MOR than the specimens with a finger length of 4 mm. The MOE of the unsteamed specimens was not affected by finger jointing, whereas, the MOE of the steamed specimens increased slightly (by 5.4%) compared to the control solid wood. It was concluded that it was better to use a 10-mm finger length and the D3 durability class of PVAc adhesives when finger-jointed furniture lumber is produced. (c) 2006 Wiley Periodicals, Inc.