Bahri BAŞARAN, A. Maruf ALASKAN, Sevgi NALBAT

Structural and physicomechanical characteristics of leatherheads used in various percussion instruments

Vurmalı çalgılarda müziksel ses; derinin mekanik etkilerle kararsız hale getirilen strüktürel bileşenlerinin titreşimidir. Bu titreşimler strüktürel özellikler ve bunlara bağlı fizikomekaniksel özellikler ile yakın ilişkilidir. Bu araştırmada kullanılan vurmalı çalgı için işlenmiş 12 adet dana derisinin strüktürel değerlendirilmesi optoanalytical tekniklerle yapılmıştır ve gerdirme, akortlama, sürekli çalma durumunda maruz kaldıkları mekanik etkilere karşı dirençlerini ve davranışlarını tespit etmek amacıyla, çekme mukavemeti, % uzama, elastisite modülü, sertlik (Shore A ve D), görünür yoğunluk gibi fizikomekaniksel özellikleri incelenmiştir.Araştırma sonuçlarına göre, vurmalı çalgı üretiminde kullanılmak üzere işlenen derilerin; giysilik, yüzlük ve saraciyelik gibi mamul derilere göre strüktürel olarak yüksek yoğunlukta; daha sıkı ve kompakt yapıda olduğu belirlenmiştir. Bununla birlikte; mekaniksel olarak da daha mukavim ve daha sert olduğu ancak; nispeten düşük uzama gösterdikleri belirlenmiştir.

Bazı vurmalı çalgılarda kullanılan dana derilerinin strüktürel ve fizikomekaniksel özellikleri

Musical sound in percussion instruments is an energy being emited through the vibrational waves from the structural components of leatherheads which becomes unstable due to mechanical agitation. This vibration is strictly bound up with the structural and therefore physicomechanical characteristics naturally available. The study was carried out on 12 leatherheads processed for percussion instrument, the structural evaluation was practiced by optoanalytical techniques and physicomechanical characteristics such as tensile strength, elongation (%), elasticity modulus, hardness (Shore A and D) and apparent density were examined in order to find out the resistance and behaviors against the mechanical effects like stretching, tuning and playing. According to the results; the leatherheads used for percussion instruments making were found to be much more tightly and compact structured, and also have high apparent density as compared to the leathers processed for garments, shoe uppers and leather goods. As consequences of compactly packed structure, for the same comparison, the leatherheads were found to have different mechanical behavior, being more resistant and having harder handle but indicating lower elongation (%).

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