Jamal Balfas
Pusat Litbang Keteknikan Kehutanan dan Pengolahan Hasil Hutan Jl. Gunung Batu 5, Bogor. Telp. 0251-8633378

Published : 96 Documents
Articles

KETEGUHAN REKAT RESORSINOL FORMALDEHIDA PADA KAYU YANG DIA WETKAN DENGAN CELCURE Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 13, No 1 (1995): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/jphh.1995.13.1.9-18

Abstract

Production  of laminated  structural  timbers   suitable  for use under severe  conditions  dates back to the development   of resorcinol and phenol-resorcinol   adhesives.    These adhesives  could provide  highly  durable  bonds  with  untreated    wood.     Because  preservative  treatment  of the - wood is commonly  required,   it  became necessary   to  investigate  the effect of the treatment on glue bond strength.This  study  examined  the  shear  strength   of resorcinol formaldehyde on the untreated  and cetcure  treated   timbers.    Additionally,   a mechanical and a chemical surface  activation treat- ments   were   imposed  lo  the  system  prior  lo  gluing.    Species   included for  the  study  were: jeungjing   (Paraserianthes    falcataria   (L.)  Nielsen,   adinandra  (Adinandra brasii  Kobuski) and pala burung (Horsfieldia sylvestris Warrb.).  Defect-free airdried wood slicks measuring  50 mm (radial) x 50 mm (tangential) x 500 mm (longitudinal)  were divided into  two groups,   of which one  group   was celcure-treated    using  an  empty-cell process  and  the  other  was remained  as control.  Each  slick   was  then    cut  into  billets  for  adhesive   lamination.    Surface  activation treatments   were made mechanically by sanding  wood surface with an 80-grit  abrasive  paper, or chemically by smearing wood surface with  IM solution of NaOH approximately 24 h before  gluing.  Resorcinol formaldehyde  was applied  to each surface  at a spread rate of  120  mg/cm2.  Panels  were clamped  at  12   kg/cm2  for  7 h as recommended  by the   adhesive  manufacturer. Each panel  was  cut   into four  shear   specimens,    of  which  two specimens  were  tested   in dry condition   and the remaining  after  24 h immersion  in water at room temperature.    Strength  loss  due to wetting was also determined.Results  showed  that bond strength  of resorcinol formaldehyde varied according  to wood species.    Jeungjing had a weaker bond strength  than adinandra and pala burung.   Preservative treatment  had  no  deteriorating  effects on dry  shear  strength,   but it did  reduce  the wet  shear strength  of  wood laminates. The  application  of surface activation treatments  was more effective on the higher extractive  contained species   (adinandra  and pala  burung) and the  unpreserved laminates.    Surface mechanical  treatment  showed a better improvement on bond strength  than the chemical   treatment.  Jeungjing   experienced  a higher strength  loss during  immersion  than
A NEW APPROACH TO OIL PALM WOOD UTILIZATION FOR WOODWORKING PRODUCTION (Part 2: Wood Modification with Organic Resin) Balfas, Jamal
Indonesian Journal of Forestry Research Vol 5, No 2 (2008): Journal of Forestry Research
Publisher : Secretariat of Forestry Research and Development Agency

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Abstract

IMPREGNASI EKSTRAK JATI DAN RESIN PADA KAYU JATI CEPAT TUMBUH DAN KARET Basri, Efrida; Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 32, No 4 (2014): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Litbang Keteknikan Kehutanan dan Pengolahan Hasil Hutan

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Abstract

Penelitian sebelumnya menunjukkan karakteristik fisis, mekanis dan keawetan kayu jati cepat tumbuh (JCT) relatif lebih rendah dibanding kayu jati tradisional.  Berdasarkan hal tersebut, perlakuan modifikasi kayu dapat dilakukan dengan perlakuan tertentu untuk meningkatkan kualitas kayunya. Penelitian ini bertujuan menyempurnakan karakteristik kayu JCT dan karet dengan perlakuan impregnasi ekstrak jati dan resin hingga mendekati atau setara dengan karakteristik kayu jati tradisional.  Dalam penelitian ini dilakukan ekstraksi serbuk kayu jati tradisional dengan pelarut metanol.  Larutan ekstrak tersebut kemudian diimpregnasi ke dalam struktur kayu JCT dan karet dengan beragam konsentrasi menurut penambahan resin organik.  Resin yang digunakan sebagai campuran dalam penelitian ini adalah sirlak dan damar, masing-masing dengan konsentrasi berat 4, 6 dan 8% dari volume ekstrak.  Hasil penelitian menunjukkan perlakuan impregnasi larutan ekstrak jati terhadap kayu JCT dan karet mampu meningkatkan stabilitas dimensi kedua jenis kayu tersebut dengan nilai ASE lebih dari 50%, hingga setara dengan stabilitas jati tradisional. Penambahan resin sirlak maupun damar ke dalam larutan ekstrak jati secara nyata dapat lebih menyempurnakan sifat stabilitas dimensi kayu JCT dan karet secara proporsional menurut konsentrasi resin. 
PENETAPAN UKURAN SASARAN SEBAGAI USAHA PENINGKATAN EFISIENSI PROSES PENGGERGAJIAN Rachman, Osly; Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 6, No 4 (1989): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4927.043 KB) | DOI: 10.20886/jphh.1989.6.4.215-219

Abstract

Two units of sawmill in Lampung (Sumatera) and three units in West-Java have been visited for the purpose of this study. Determination of target size on each sawmill was firstly done by collecting data from thickness measurements of 100 board samples. The data was then calculated using the most common formulas used for determining the lumber target size.The result of the study revealed that actual size produced by two sawmills surveyed were higher than target size, ranging from 1.08 to 1.58 mm. The actual size from three other sawmills were lower than target size, ranging from 0.26 to 2.18 mm. The sawmill A has apparently the best sawing capability. This was indicated by the smallest thickness range either within or between board i.e. 0.89 mm and 0. 79 mm. Meanwhile, its total sawing variation was smallest i.e. 0.49 mm.The result of this study was an indication that there is a need for improving the efficiency of sawing process through the application of target size determination.
PENENTUAN PENUMPULAN PISAU PADA PERMUKAAN KAYU Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 12, No 2 (1994): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1389.45 KB) | DOI: 10.20886/jphh.1994.12.2.109-113

Abstract

The wear of wood cutting tools is, generally, the process which makes a usable tool unfit for continued use. The replacement of the worn cutter either by reconditioning or substitution of a new one represents a necessary cost which can be minimized by controlling tool wear. Numerous studies have been conducted through direct observations on the cutting edge using a variety of photographic methods. Such observations are quite complicated and can hardly be introduced to industrial practices. This study is aimed to explore a possibility of determining cutting tool wear indirectly through the work piece observation. It is based on assumption that knife blunting has a direct bearing on the quality of the finished product, i.e., changing the geometry of cutting marks on the wood surface.Boards of two wood species, rasamala and mangium, were seasoned to air-dry condition and planed using new sharp knives at one feed speed of 30 m/min. Observations were carried out sequentially at 5 planing distances, i.e., 10, 20, 40, 80 and 160 m. Cutting marks geometry on the wood surface was distinguished by rubbing the surface gently with a carbon paper. Measurements of cutting marks and the width of cutting peak were undertaken using a digital calliper. Results showed that values of cutting marks and width of cutting peaks markedly increased with increasing planing distances. Blunting process was significantly affected by wood species. Knives used for planing rasamala boards blunted quicker than those used for mangium. These, to some extend, revealed a possible use of cutting marks structure on wood surface for determining the wear of cutting edge.
SIFAT BALOK KOMPOSIT KOMBINASI BAMBU DAN KAYU Abdurachman, Abdurachman; Hadjib, Nurwati; Jasni, Jasni; Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 33, No 2 (2015): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Litbang Keteknikan Kehutanan dan Pengolahan Hasil Hutan

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Abstract

PENANGGULANGAN MASALAH SERAT BERBULU PADA KAYU LABU (Endospermum spp.) SEBAGAI BAHAN BAKU PENSIL Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 29, No 1 (2011): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1569.325 KB) | DOI: 10.20886/jphh.2011.29.1.78-85

Abstract

Dalam beberapa tahun terakhir kayu labu (Endospermum spp.) telah digunakan sebagai bahan baku alternatif oleh industri pensil di Indonesia. Namun terdapat beberapa keluhan teknis dalam penggunaannya sebagai bahan baku pensil (pencil slat). Salah satu keluhan utama yang dijumpai dalam proses produksi jenis ini adalah kecenderungan munculnya serat berbulu (fuzzy grain) pada permukaan pensil kayu labu. Dalam penelitian ini dilakukan upaya penanggulangan serat berbulu dengan perlakuan rendaman bahan baku pensil pada larutan resin JRP1 dengan beragam konsentrasi dan waktu rendaman. Konsentrasi resin terdiri dari dua taraf, yaitu 5 dan 10%, sedangkan waktu rendaman bervariasi dari 5, 10, 30 dan 60 menit. Hasil penelitian menunjukkan bahwa perlakuan rendaman resin JRP1 mampu mengatasii masalah serat berbulu pada permukaan pensil, sekalipun menggunakan konsentrasi resin terendah dan waktu rendaman paling singkat. Perlakuan ini menyebabkan penambahan berat pada pensil slat sebesar 2 sampai 4% tergantung pada taraf konsentrasi resin dan lama waktu rendaman. Deposisi resin pada pensil slat menyebabkan kenaikan biaya sekitar Rp 60 per pensil slat.
SIFAT PEMESINAN BEBERAPA JENIS KAYU ASAL IRIAN JAYA Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 12, No 3 (1994): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (9704.599 KB) | DOI: 10.20886/jphh.1994.12.3.84-88

Abstract

Nine wood species collected  from  Sarong,  Iriarn Jayo,  were observed for  their machining properties.   Sawing characteristics (feed speed and surface smoothness) of each species were observed to  determine its cutting-ability. Other machining properties  (planing, shaping,  boring.  turning and sanding)  were determined according  to the modifled  ASTM D-1666 method  as  festly   described in  the  Forest  Products Research  Institute  Report  No.  160  (1982).  Planing and shaping of samples  were  observed  in wet  condition (above EMC) and again after air-drying, whereas  the remaining  properties  were  observed  only  at  air-dry condition.Results showed that most of the species couid be sawn fairly easily, and  indicaud a variation  in cutting surface qualjty, ranging from rough  to  smooth.   One species,  i.e.,   goh  (T.richadenia phiilippinensis)   was  quite difficult  to  saw for  its  irregular  (partly nterlocked) grain orientation and very  high density.   Testing of wood  samples in wet condition produced  a satisfactory planing and shaping  quality for most  wood species.  However,  testing   at   air-dry  condition  significantly revealed  a better  machining  quality. Based on the  machining characteristics  observed  on  the  nine wood species from  Sorong,  it is recommendable  to use the timbers  for  woodworking purposes.   
KARAKTERISTIK KAYU KELAPA SAWIT TUA Balfas, Jamal
Jurnal Penelitian Hasil Hutan Vol 27, No 3 (2009): Jurnal Penelitian Hasil Hutan
Publisher : Pusat Penelitian dan Pengembangan Hasil Hutan

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2676.552 KB) | DOI: 10.20886/jphh.2009.27.3.223 - 234

Abstract

Kayu kelapa sawit yang berasal dari kegiatan penjarangan diketahui memiliki karakteristik yang rendah dibandingkan dengan kayu komersil.  Namun demikian tidak ada informasi yang menguraikan karakteristik kayu sawit yang berasal dari pohon tua. Penelitian ini mengevaluasi karakteristik kayu sawit yang berasal dari tanaman usia tua dan usia peremajaan.   Semua pohon contoh diambil dari blok perkebunan sawit yang sama di wilayah Jasinga, Jawa Barat. Hasil penelitian menunjukkan bahwa pohon sawit tua memiliki batang  dengan ukuran diameter lebih kecil, lebih tinggi dan volume yang sama dengan pohon sawit peremajaan.   Kayu sawit tua memiliki jumlah jaringan vaskular lebih banyak dibandingkan dengan jaringan tersebut pada kayu sawit peremajaan.  Perbedaan struktur menurut umur pohon pada kayu sawit menyebabkan kayu sawit tua lebih baik secara fisis, mekanis maupun pemesinan daripada kayu sawit peremajaan.  Kayu sawit tua memiliki kesetaraan beberapa sifat teknis dengan kayu kelapa dan kayu komersil lainnya.
NEW APPROACH TO OIL PALM WOOD UTILIZATION FOR WOODWORKING PRODUCTION Part 1: Basic Properties Balfas, Jamal
Indonesian Journal of Forestry Research Vol 3, No 1 (2006): Journal of Forestry Research
Publisher : Secretariat of Forestry Research and Development Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20886/ijfr.2006.3.1.55-65

Abstract

An explosive development in oil palm plantations in the country has produced a consequence in the generation of  plantation wastes. The  disposal of these wastes  has created  an  enormous environmental problem that some practical solution to their economic utilization has to  be sought.  A series of experiments have been accomplished to observe the possibility of converting the oil palm stem into valuable woodworking products. The  first stage of  this effort was determining basic characteristics of oil palm wood.  Results in general showed that the wood has a great characteristic variation across and along the stem, which may develop problems in its utilization. Characteristics of this wood also vary according to species variety.  Quality degradations of oil palm wood were mostly happened during drying process; hence, modifications to upgrade quality should be undertaken before or within the drying process.