Strength properties of longitudinally glued spruce wood (Picea abies Karst) were researched using a toothed adhesive layer and spruce wood of different moisture. We took several lamellas of spruce wood and sort them into 3 moisture groups. The first group contained lamellas with high percentage of moisture 46 %, the second group 30 %, and the third 10%. We sawed lamellas into halves and then glued them back together with assistance of finger joint and one - component polyurethane glue, MITOPUR E20 produced by Mitol from Sežana. Afterwards we processed glued lamellas into dimensions demanded by DIN 52 186, cross- section 20 * 20 mm and length 470 mm. We dried the processed lamellas in a drier to moisture of 14 %. Our tests were performed at Biotechnical faculty on Zwick Z100 machine, used for testing mechanical characteristics. Modulus of elasticity and bending strength demanded by DIN 52186 were tested. We came to conclusion that the glue we used was appropriate for gluing wet or humid spruce wood. By increasing the moisture of wood the modulus of elasticity was increasing and bending strength was decreasing. The best results we came across were at the moisture of 10 %.
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