OPTIMASI PARAMETER PROSES PEMESINAN CNC MILLING TERHADAP KEKASARAN PERMUKAAN KAYU JATI DENGAN METODE TAGUCHI

Nur Firstiawan. PARAMETER OPTIMIZATION OF MACHINING CNC MILLING PROCESS OF SURFACE ROUGHNESS TEAK WOOD WITH METHOD TAGUCHI. Thesis, Surakarta: The Faculty of Teacher Training and Education. Sebelas Maret University, September 2012. The purpose of this research is to know: (1) Effect of spindle speed variation, feedrate, depth of cut and direction of the wood grain pieces (longitudinal, radial and tangential) to the level of surface roughness result type CNC milling machining process ZK 7040 at teak wood material. (2) Knowing which parameters that produce optimal roughness values on CNC milling machining process on the material type ZK 7040 at teak wood material, using the Taguchi method. Teak wood machining process using CNC milling machine type 7040 with the ZK control SIEMENS SINUMERIK 802S in SMK SAKTI Gemolong. The testing of moisture content done in Laboratory of Materials, Civil Engineering, Sebelas Maret University. Surface roughness test was done in metrology laboratory, Mechanical Engineering Diploma Program, Vocational School, Gadjah Mada University. Optimization methods used in this study the Taguchi method. TAGUCHI ANOVA (Analysis of Taguchi Varian) in Minitab 15 software help to determine the performance characteristics of the machining parameters. The results of CNC milling machining process on the material type ZK 7040 teak was: (1) higher spindle speed, will produce a surface roughness values less ie at level 3 = 3000 rpm; highe feedrate, will produce a surface roughness values greater ie at level 3 = 1200 mm/min; higher depth of cut,will produce value greater surface roughness is at level 3 = 6 mm, and more dry wood on the variation of direction wood grain pieces, would result in the value of the smaller surface roughness is at level 1 = direction tangential cutting. (2) Parameters that yield optimal surface roughness values are at 3000 rpm spindle rotation speed, feedrate 400 mm/min, depth of cut 2 mm and tangential cutting direction. The feedrate has the most effect with delta ratio S/N 3,78 and the direction of cutting wood has the smallest contribution is a delta ratio S/N 1,92. (3) The optimal roughness is 4,12 ± 0,42 μm. Key words: Wood machining, CNC milling, surface roughness, and Taguchi method