Pengaruh Peneresan Terhadap Mutu Finir Kayu Sengon (Falcataria moluccana (Miq.) Barneby & J. Grimes)

Yuris Orchita Hapsari, Ir. Tomy Listyanto, S.Hut.. M. Env. Sc., Ph.D., IPU. ASEAN.Eng

2024 | Skripsi | KEHUTANAN

Kayu sengon (Falcataria moluccana (Miq.) Barneby & J. Grimes) sebagai bahan baku kayu lapis diharapkan memiliki mutu finir yang baik. Akan tetapi, dalam pengupasannya menjadi finir, proporsi kayu juvenil sengon dapat menghasilkan berbagai permasalahan seperti menimbulkan banyak cacat pecah, menurunkan grading finir, dan variasi ketebalan. Selain itu, permasalahan cacat juga muncul akibat kadar air segar finir yang tinggi dan rentang kadar air segar yang besar pada dekat hati menuju dekat kulit. Salah satu metode yang diduga dapat memperbaiki permasalahan tersebut adalah peneresan. Penelitian untuk mengetahui lama waktu peneresan dan kedudukan arah radial diperlukan untuk mengetahui seberapa jauh pengaruhnya terhadap mutu finir. 

Penelitian ini menggunakan metode rancangan acak lengkap dengan dua faktor dan tiga aras yaitu lama waktu peneresan (tanpa peneresan, peneresan 3 bulan, dan peneresan 12 bulan) dan kedudukan radial (dekat kulit, tengah, dan dekat hati). Pembuatan dan pengujian sampel finir dilakukan berdasarkan SNI 7836 : 1 : 2012 sedangkan pembuatan sampel kadar air segar kayu dilakukan berdasarkan British Standard nomor 373 tahun 1957.

Hasil Penelitian menunjukkan bahwa kayu tanpa peneresan peneresan 3 bulan, dan 12 bulan memiliki rerata kadar air segar sebesar 94%;87,6%; dan 44,25% secara berurutan. Pada uji kadar air segar finir, finir tanpa peneresan, peneresan 3 bulan dan peneresan 12 bulan memiliki rerata kadar air segar sebesar 95,77%, 90,24%, dan 37,80%. Pada uji penyusutan finir, Peneresan 12 bulan mampu menurunkan penyusutan radial finir hingga 0,85?n tangensial finir hingga 0,62%. Peneresan 3 bulan belum mampu menurunkan penyusutan finir. Rerata panjang pecah finir tanpa peneresan, peneresan 3 bulan, dan peneresan 12 bulan pada seluruh sampel adalah 122,8 cm, 53 cm, dan 138,3 cm. Rendemen finir face dari finir tanpa peneresan, peneresan 3 bulan, dan peneresan 12 bulan adalah 77,7%, 93,33%, dan 61,11%. Secara umum, finir dari peneresan 3 bulan menunjukkan sifat yang lebih baik dibandingkan tanpa peneresan dan finir dari teresan 12 bulan. Penelitian ini menunjukkan adanya potensi perlakuan peneresan pada pohon sengon sebagai bahan baku finir. 

Sengon wood (Falcataria moluccana (Miq.) Barneby & J. Grimes) as a raw material for plywood is expected to have good veneer quality. However, during the peeling process to become veneer, the proportion of juvenile sengon wood can lead to various issues such as causing many splits defects, reducing veneer grades, and thickness variations. Additionally, defect issues may arise due to high MC (Moisture Content) in veneer and a wide range of MC nearby pith towards the bark. One method believed to reduce these problems is girdling. Research is needed to determine the duration of girdling and the radial position to understand how girdling affect the veneer quality.

This research used a completely randomized design with two factors and three levels: girdling duration (ungirdled, 3 months of girdling, and 12 months girdling) and radial position (nearby bark, middle, and nearby pith). The preparation and test of veneer samples were conducted in accordance to SNI 7836:1:2012, while the preparation of green wood moisture content samples was based on British Standard number 373 of 1957.

The results show that wood ungirdled, 3 months girdling, and 12 months girdling have an average MC of 94%, 87.6%, and 44.25%, respectively. In the veneer MC test, veneer ungirdled, 3 months girdling, and 12 months girdling have an average MC of 95.77%, 90.24%, and 37.80%, respectively. In the veneer shrinkage test, 12 months girdling shows better properties compared to 3 months girdling. 12 months girdling can reduce radial veneer shrinkage up to 0.85% and tangential veneer shrinkage up to 0.62%. The average length of veneer split ungirdled, 3 months girdling, and 12 months girdling in all samples is 122.8 cm, 53 cm, and 138.3 cm, respectively. The veneer face yield from ungirdled, 3 months girdling, and 12 months girdling is 77.7%, 93.33%, and 61.11%, respectively. Overall, veneer from 3 months girdling shows better properties compared to veneer ungirdled and veneer from 12 months girdling of peeled logs. This research indicates the potential of girdling treatment on sengon trees as a raw material for veneer. 

Kata Kunci : Veneer, Girdling, Veneer Quality