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There are several ways to assess machinability, viz. forces that are working during machining, the surface roughness of machined part, chip formation, and tool performance. This article aims to observe the machinability from the tool performance perspective when machining with minimum quantity lubrication (MQL). The MQL device can either be time-controlled or temperature-controlled using an Arduino. The machining was carried out on a conventional lathe toward a bar of AISI 4330 using carbide coated insert tools. The experiments were carried out using Taguchi design L9, by the varying depth of cut, coolant composition and method of applying the coolant. Tool performance was evaluated by tool deterioration value. There are four levels of tool deterioration according to its severities after machining. Analysis of variance shows that depth of cut more influence to the tool performance than the coolant application method by 32.69% and 12.82% each, respectively. However, it is proof that MQL with temperature-controlled would contribute to the minimum tool deterioration.

The cutting force that reacts to cutting tool and workpieces will result deflection. Deflection is the cause of product deviation and vibration sources that can shorten the life of the cutting tool. Simulation of machining process is carried out to get an estimate of cutting force in some machining process conditions., then compare it to the experiments. The research aims to find out the influence of spindle rotary speed, feed rate and depth of cut on cutting forces in turning process with cutting tool HSS and workpiece Al 6061. This research uses three-dimensional simulation method using Third Wave AdvantEdge software. Following by comparison between the simulation with the experiments results. The simulation was in accordance to the experiments in term of the magnitude of the forces, from the biggest they are tangential, axial, and radial force respectively. Cutting force will decrease with increased spindle turning speed. Cutting force will increase with the rising feed rate and depth of cut. However, the simalution still highly deviate from the experiments at the rate of 71%, 44.3%, and 21.3% for axial, radial and tangential forces respectively. The possible cause of these high errors relates to forces measuring method in experiments.

Two purposes of painting of the automobile body, i.e. protection and aesthetic. For the aesthetic one, scientifically measured its glossiness. The purpose of this study was to determine the effects of painting parameters using a spray to its glossiness. Three parameters varied were: (i) comparison of paint composition and thinner (1:1.2; 1:1.4 and 1:1.6), (ii) spraying distance (110 mm, 130 mm and 150 mm), and air pressure (3.5 bar; 4.5 bar and 5.5 bar, while the glossiness measured in gloss unit (GU) using a gloss meter. The experimental design method used was the response surface method with Box-Behnken design. A series of tests were carried out prior to ANOVA and optimization with Minitab: (i) lack of fit test, (ii) simultaneous parameter test, (iii) the coefficient of determination test, (iv) identical test, (v) independent test and (vi) normal distribution test. Out of three parameters, the most influential one is composition with a coefficient of mathematical equation of 6.592. In this study, the highest value in the 10th trial was 57.3 GU which was occurred when the parameters used were: distance of 130 mm, composition 1: 1.6 and pressure 3.5 bar. On the contrary, the smallest value GU in the 7th experiment was 35 GU with a distance of 110 mm, composition 1:1.4 and pressure 5.5 bar. From processing data using Minitab, the maximum gloss value was 58.76 GU with distance 116.86 mm, composition 1: 1.6 and pressure 3.5 bar. Keywords: painting, Box-Behnken design, gloss meter

This study aims to observe the tool deterioration following application of minimum quantity lubrication method (MQL). The designed MQL system is completed with an Arduino controller system which was able to be either manually-controlled or automatically-controlled. The tool used in this study is DCMT 11 insert type. The Taguchi method using the Orthogonal Array L9 design was used to compile the design of experiments with variations in depth of cut, coolant composition, and cooling fluid application methods. Each variable consists of three levels. Tool deterioration evaluated by observing it under an optic microscope from three sides of the tool. There are four levels of tool deterioration. The value of tool deterioration of each tool is the accumulation of each side view. ANOVA analysis found that depth of cut, cutting tool composition and method of applying coolant influence tool deterioration in percentage by 32.69%, 17.30 % and 12.82% respectively. Moreover, the minimum tool deterioration would be achieved when using the parameter combination of depth of cut of 1.6 mm; mixture composition of 3:7; and using the temperature-controlled MQL.