The purpose of this research was to designing and fabrication a Computer Numerical Control (CNC) based router machine for wood engraving machine. The idea behind this research was to help the traditional woods craft men in Bali to make a craft more productive and more efficient. The router machine that is made is driven by the driver in the form of a stepper motor, with a 3 axis motion so that the results of wood engraving obtained are precision and homogeneous. G-code program used on CAM processing uses MACH 3 software. The workspace of the machine was 800 mm x 500 mm. The stepper motor driven with TB 6600 driver and combined with ball screw on linear bearing to make the motion more precisely. The test result showed that the machine accuracy is about 99.5 percent for X and Y axis and 96 percent for Z axis.

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In this study, a redesign to a clove  dryer simulation tool using  exhaust heat from radiator as a source of heat energy has been done. The dryer  simulation tool consists of reservoir tank, a heater, a pump to circulate the water in the system, a radiator as a heat exchanger and a drying chamber with 2 shelves. The redesign stage is carried out by fixing the piping insulation system, changing the pipe and adding valve controls to vary the velocity of the fluid flow. Variations made are variations in the mass flow rate of 0.09 kg / s and 0.18 kg /s with a constant air flow rate of 1 m/s. The results of the analysis show that at a higher mass flow rate of 0.18 kg/s the average rate of heat transfer from the radiator air side is higher, which is around 3971.65 watts. The effectiveness of the radiator will also be higher at a higher mass flow rate, the average is 0.34 at a mass flow rate of 0.09 kg/s and 0.43 at a mass flow rate of 0.18 kg /s. For drying rates with a load of 2 kg of cloves with a higher flow rate of liquid will be faster, which is about 5 hours with a flow rate of  0.18 kg/s and 6.5 hours at a flow rate of 0.09 kg/s

In this study, the heat effectiveness and energy efficiency of the clove drying machine with control of temperature and relative air humidity were analysed. The data were carried out experimentally on a clove dryer machine that has 3 racks with staggered arrangement by varying the speed of the air flow into the drying chamber. The hot air produced from a heater and blown to the drying chamber used a fan with 3 various speed rate (1.9 m/s, 2.3 m/s, 2.8 m/s). The heat distribution on each rack was observed and analysed and compared with the energy requirements of the machine. The result showed that the heat flow on the rack evenly distributed. The fluid flow variation has the important effect. The heat will more effective with the lower air flow speed, which the higher heat transfer (q) to the clove from the heater depend on the air flow speed with the higher value 72.78 watt at the lowest positions rack with hot air speed 2.8 m/s. The energy efficiency of the machine was about 37 percent, with the highest value 39.27 percent at the air speed 2.3 m/s.