Wetting and adhesion at gluing of fast growing species was studied. Phenol-formaldehyde glue GP 3110 and 5 commercially less important wood species (birch, black alder, poplar, green pine and willow) were used. A microscope, digital photo camera and computer were used to find the contact angle of phenol-formaldehyde glue drop on specific wood species. 2 lamellas were hot glued together. Testers made for measuring the shear strength were exposed to different conditions (acclimatisation, soaking in water, boiling). The shear test was performed with Zwick Z100 universal testing machine. Contact angles did not differ much among specific species. The lowest contact angle was measured at green pine wood (lowest wood density), the highest at birch wood (highest wood density). It was also found that the shear strength of the adhesive bond of the testers was influenced by the conditions under which they were treated and tested. Wood density also influenced shear strength.
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