Methodological characteristics of wood hardness determination

Abstract

According to the Standard wood hardness is found by two methods: the main one – by pressing the standard puncheon into 5.64 mm in wood and the additional one by pressing the puncheon into 2.82 mm, the calculation of numerical values of hardness is done according to the formulas. The investigations found out that the numerical data received by the mentioned above methods differ essentially. The additional method gives overstating value in determining cross section hardness of dry wood by 12.1% and by 5–6% of moist wood, and in determining radial section hardness it gives understating values by 20.3% of dry wood and by 27.7% of moist wood. The paper gives an explanation of the difference in values received by both methods. Thus in defining wood hardness the additional method cannot be used instead of the main one due to its large error.