Marina A. Alipon*
Department of Science and Technology (DOST) – Forest Products Research and Development Institute (FPRDI), College, Laguna 4031, Philippines,
alipon07marinaa@yahoo.com.ph/aliponmarina@gmail.com Gil B. Dolotina
DOST-FPRDI, College, Laguna 4031, Philippines, gilbdolotina@gmail.com Gerwin P. Guba
DOST-Advanced Science and Technology (ASTI), Diliman, Quezon City, Philippines, gerwin.guba@gmail.com
Alvin E. Retamar
DOST – ASTI, Diliman, Quezon City, Philippines, retamare@gmail.com Grecelda A. Eusebio
DOST – FPRDI, College, Laguna 4031, Philippines, ycelaeusebio@yahoo.com
*Corresponding author
Abstract
The Forest Products Research and Development Institute (FPRDI) in collaboration with the Advanced Science and Technology Institute (ASTI) of the Department of Science and Technology (DOST) and YONGDEN Company developed a digital resistance type wood moisture meter for the furniture and handicraft industry.
The digital moisture meter is an improved version of the analog resistance type moisture meter developed by FPRDI in 2001. Similar to the analog type, it equipped with a parallel pair of needle - type electrodes 25 mm apart that can detect moisture content (MC) in wood to about 25 mm depth.
The digital meter can measure can measure wood MC within 6 to 25%. The MC reading is automatically displayed and read without adjusting any selector switch as in analog. In addition to the 12.5 mm built-in needle to the meter for measuring thin wood, it has a probe hammer with 50 mm needles that can replace the small needle to measure MC’s of thicker wood samples/products.
The wood moisture meter case design measures 60 mm x 43.0 mm, twice smaller than the analog. The operation is much simpler and the cost is cheaper than the analog.
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Keywords: digital wood moisture meter, analog resistance meter, moisture content
Introduction
The Philippine is a major global player in the furniture industry. Philippine furniture ranks among the world's best, earning for the country the distinction of being the "Milan of Asia" because of its elegance and high quality craftsmanship. In an industry dominated by small and medium entrepreneurs, it has succeeded in becoming a dollar earning industry (www.cfipnet.com).
An estimated 15,000 local furniture companies are actively supporting the industry and provide employment to a total of 481,500 direct workers and 300,000 sub-contractors. Only 10% of these establishments are considered large companies. The remaining 90% are classified as small and
medium enterprises (SMEs). Notably, SME's make- up bulk of the 2,500 furniture companies engaged in exports (Furnitureman 2017).
On the other hand, the handicraft industry is one of the oldest industries in the country. The handicraft manufacturers are also dominated by SME's. with ninety-six (96) percent of the country's handicraft firms classified as either cottage and small enterprises. For basketry alone, there are about 5,000 basket manufacturers with l50 firms classified, as large scale and the rest are as small and medium scale firms. The industry is labor intensive, directly employing 40,000 and 1,000,000 workers indirectly, spread over the basket producing regions in the country (Pearl 2 2004)
The international competitiveness of the wood-based furniture and handicraft industry depends on product quality. In turn, product quality depends largely on the moisture content (MC) of the materials used. The most convenient and fastest way of determining moisture content is with the use of moisture meter.
Moisture meters, however, are all imported and could be expensive. Moreover, imported meters are calibrated using foreign wood species as reference points, i.e. American-made moisture meters are calibrated using Douglas fir while European-made moisture meters are calibrated using beech. When used with local wood species, these moisture meters give large discrepancies in moisture content readings necessitating recalibration of the meters to give accurate MC readings. The calibration process is time consuming and can be costly (P1,500 (US$30) - P2,000 (US$40/species).
Most of the small and medium furniture and handicraft enterprises do not have moisture meters. There is thus a need to develop moisture meters that are cheaper than imported ones and calibrated to local species. With the moisture meters, the SME's could afford to buy this utility for a more reliable measurement of wood's moisture content, thus eventually improving the quality of their products.
The Forest Products Research and Development Institute (FPRDI) developed in 2001 a needle-type resistance analog moisture meter for wood (Figure 1). The moisture meters is made of a simple transistorized circuit supplied with a 9 volts battery, equipped with a pair of parallel needle-type electrodes 25.4 mm apart and a sliding hammer the drives the needles into the wood. The needle-type electrodes can be used for specimens up to about 25.4 mm in depth. The meter reads the resistance of wood samples to electric current and correlates this resistance to moisture content which values were previously obtained through the standard oven-drying method of MC determination. The FPRDI-developed moisture meter can be used effectively within a range of 6 - 25% moisture content. The meter was calibrated to yemane (Gmelina arborea Roxb.) (Verbenaceae), an industrial tree plantation species widely planted in the Philippines, and correction factor for other 9 wood species commonly used for furniture making were derived.
Around 400 units of the FPRDI-developed analog moisture meter have been fabricated and availed of by various wood-using firms. The introduction an application of the FPRDI moisture meter has been serving as an important tool in enhancing production capabilities and product quality of small and medium enterprises wood manufacturers. The following change in the level of productivity was met:
1. Increased production – A moisture meter is necessary in monitoring the quality of wooden furniture. It provides a means of guaranteeing that the wood used in the product has been dried to the required moisture content (MC). This prevents guesswork to the producers and acquires the
confidence to claim that his products met the required MC standards. Quality products improve a firm’s reputation and encourage repeat purchases and referrals from satisfied buyers.
2. Decreased cost of production – Back jobs are common in small firms that cannot afford good quality wood moisture meters. Back jobs are usually in the form of checking and or cracking of wood in fabricated furniture. Adoptors of FPRDI moisture meter estimate that the average cost of these back jobs are 20% of production cost. For dining chair with an average production of
PhP2,000.00 (US$40), cost of back job is P400.00 (US$8) per chair. Thus, savings arising from the reduction of back jobs.
Some users found the use of the FPRDI-developed analog moisture meter complicated because it involves 3 switches for 3 ranges of MC limits, namely: A= 7 - 12% MC; B= 12 - 17% MC and C= 17-25% MC. If the MC reading is over 12% MC, then the switch should be turned from A to B; and if over 17% MC, from B to C. Moisture content value should also be read approximately 5 seconds after the needles have penetrated the wood sample. Thus in 2007- 2008, the Forest Products Research and Development Institute (FPRDI) in collaboration with the Advanced Science and Technology Institute (ASTI) of the Department of Science and Technology (DOST) and YONGDEN company developed a digital resistance type wood moisture meter for the furniture and handicraft industry (Figure 2).
The digital moisture meter is an improved version of the analog resistance type moisture meter developed by FPRDI in 2001. Similar to the analog type, it equipped with a parallel pair of needle - type electrodes 25 mm apart that can detect moisture content (MC) in wood to about 25 mm depth.
MC reading is automatically displayed and read without adjusting any selector switch as in analog.
The wood moisture meter case design measures 60 mm x 43.0 mm, twice smaller than the analog. The operation is much simpler and the cost is cheaper than the analog. As of 29 February 2008, several companies have expressed desire to avail of the unit. There had been numerous orders received from phone calls and e-mail. The digital wood moisture meter is expected to be out in the market on or before March 30, 2008.
With the development and introduction of the FPRDI wood moisture meter in the local market, the importation of the expensive moisture meter will provide opportunities to local manufacturers to buy and make use of the equally efficient and low cost meter. It is not only the community that benefited but the national economy as well.
Figure 1.Needle type resistance analog wood moisture meter.
Figure 2. Design of the FPRDI digital wood moisture meter.
Figure 3. FPRDI digital wood moisture meter box casing.