No abstract

The increase use of wood products for outdoor arises from warmth color and amenity properties of wood. However, wood is naturally degraded in term of color changes and finishing layer percentage after outdoor exposure. This paper presents wood color change and finishing layer durabillity after one year outdoor exposure. Five lesser known wood species from Riau were coated transparently using acrylic, enamel, polyurethane, ultran lasur ultra violet (UV), and ultran politur P-03 UV prior to outdoor exposure. Wood color differences were assessed according to CIELab system and coating film coverages were digitally analyzed by ImageJ software. The result showed that natural wood color turned into greyish pale after one year outdoor exposure. Color changes are relatively high in the first month then moderate and little changes every month there of. Finished layer wood samples were more resistant to weathering than unfinished surfaces. Finishing material of enamel (ET), lasur (LSR), and P03 (PP) experienced better coverage than acrylic and polyurethane finish. Finishing layer is gradually degraded, then re-finishing is necessary for optimal outdoor protection. Relationships between finishing coverage and color change showed medium correlation, where the greater finishing coverage, the greater the color changes.

The objective of the study was to determine the effect of various layer compositions on the properties of 3-layer vertically glued laminated bamboo beam (LBB). Bamboo strips for LBB fabrication were prepared from mature culms (± 4 years old) of andong bamboo (Gigantochloa pseudoarundinacea (Steud.) Widjaja) collected from private gardens in West Java. The strips were pre-treated by soaking them in 7% boron solution for four hours. Three-layer LBBs were manufactured with six different layer compositions, including bamboo combination with wood planks of manii (Maesopsis eminii Engl.) or sengon (Falcataria moluccana (Miq.) Barneby & J.W. Grimes) as the core layer. The LBB was manufactured using Water Based Polymer-Isocyanate (WBPI) adhesive. The glue spread and cold pressing time 2 applied were 250 g/m and one hour, respectively. Results showed that the average density, moisture content, thickness 3 swelling, and width expansion of LBB were 0.65 g/cm ; 11.1%; 2.09%; and 1.99%, respectively. No delamination occurred in all samples using WBPI adhesive, which indicates high bonding quality. The average bonding strength and 2 percentage bamboo failure (dry test) of LBB were 61.6 kg/cm and 90%, respectively. The physical and mechanical properties of LBB were significantly affected by the layer composition. The presence of wood laminates as the core layer of LBB and the cross wide orientation of the core layer decreased mechanical properties of LBB. On the contrary, the presence of cross-layer in LBB structure increased dimensional stability of the produced LBB.Three-layer thick laminated bamboo beam made of vertically glued andong bamboo strips with various constituted layer composition and all constitued layers laminated together in parallel grain direction had strength values comparable to those of class II of solid wood strength, eventhough the core layer was made of sengon or manii planks.

Kekabu is a trade name of Bombax ceiba L. wood, which is popularly known as kapok or randu wood. It is formerly named Gossampinus malabarica DC. Merr. and belongs to family Bombacaceae. In some area kekabu wood is mixed in consignments that are mainly comprising wood of Durio spp. and traded as 'durian wood'. Kekabu's heartwood is not clearly demarcated with its white yellowish sapwood. Wood texture is smooth and even, so that clean yellowish kekabu wood appearance is potentially developed as luxury timber. However, kekabu is a lightweight wood. The average density is about 0.30 g/ cm' that ranges from 0.12 to 0.51 g/cm3 (Oey, 1990). Due to its low density, kekabu wood has not been utilised as furniture as well as construction materials, making it traded cheaply in local market (Ba and Nghia Tin, 1998). Density is the weight of substances per unit of volume. In this case, wood density is the weight of wood cell components that build wood structure per unit of volume. It has a positive relation to the thickness of the wood cell wall and is influenced by variation in the relative proportions of different cell types and their dimensions in wood material (Koehler, 1924;Jane, 1970). In a piece of wood, for example, higher density wood has thicker cell walls.

Macroscopic image database of Indonesian commercial timber “LignoIndo” has been developed to support the development of a computer vision-based wood identification system. A total of 809 wood species were taken their macroscopic images by using digital loupe at two magnifications: 50 times and 200 times. All of these timber species are Indonesian commercial timber listed in LIU (License Information Unit) in November 2016. Cross section images of 186 wood species listed in the Ministry of Forestry Degree No 163/2003 were also collected by using mobile phone camera that was attached with 60x magnify lens, as the basis data to the mobile application of automatic wood identification tool (AIKO). The number of wood species in this database will continue to grow as the number of commercial wood species increases. Besides, the number of replicates of specimens for each species of wood can also continue to be added to accommodate wood variations in the same species, the same species from different trees, and different geographic locations. This paper presents data collection methods and summaries of wood data that have been collected including trade name, botanical name, family, durability classes, strength classes, commercial class classification, conservation status, and recommended utilization.