This digital milling machine with computer numerical control is intended for technology workshops and STEM laboratories of educational institutions. It machines wood, plastic and metal: it cuts contours of a given shape, removes a layer of material to obtain relief surfaces and applies engraving, all according to a program prepared in advance on a computer. The machine is used in technology and STEM lessons and in club work on the basics of digital manufacturing. Work with it is organised by a teacher or a master of industrial training, students work under direct supervision, and the recommended age of learners is from 10 years, that is pupils of grade 5 and above.
Movement is performed by three controlled axes: the table with the workpiece travels in the longitudinal and transverse directions, while the spindle unit moves down and up vertically. Each direction is driven by stepper motors of the 42 × 48 mm frame size acting through screw pairs with a trapezoidal thread on chromed guide shafts, and the control board reads the control program in G-code format and sets the travel path and the spindle rotation speed from it. The working field is 300 × 180 mm and the vertical travel of the spindle unit along the Z axis is 78 mm. The spindle diameter is 52 mm, the spindle motor power is 500 W and the rotation speed is 12000 rpm; the travel speed is 5000 mm per minute, the feed speed during machining is 2000 mm per minute, the acceleration is 200 mm per second squared and the machining accuracy is ±0.1 mm. Safety and control elements are an emergency stop button, limit switches on the X, Y and Z axes and a sensor of the zero level of the Z axis. The machine is controlled from a personal computer running Windows 7, 8, 10, Linux or macOS. The drives and the spindle are powered with 48 V direct current from a mains power supply unit and the power consumption is 500 W. The design provides for installing a laser module 40 mm wide in place of the milling spindle. Overall dimensions are 485 × 415 × 374 mm and the weight is 11 kg.
The set includes the milling machine equipped with computer numerical control and three controlled axes, with limit switches and a zero position sensor on the Z axis — 1 pc; a 48 V mains power supply unit — 1 pc; a universal vice for fixing the workpiece on the machine table — 1 pc; a set of milling cutters for metal, end, ball and tapered — 1 set; a special tool set for operating the machine and for the final finishing of the products — 1 set; a set of safety goggles for work with the machine — 1 set; consumables for making products for student learning projects calculated for one academic year, namely wood, plastic and aluminium; computer software that makes it possible to prepare control programs and to control the machine from a personal computer — 1 set; methodological materials for use in the educational process — 1 set; the passport with the warranty coupon — 1 pc; and individual transport packaging — 1 pc. The machine is supplied assembled and ready for connection through the mains power supply unit from the set; the laser module is not part of the standard set and is obtained separately if it is needed.
The machine is placed on a flat stable surface of a laboratory table or a workbench that rules out vibration during work. The mains power supply unit is connected to a 220 V socket through a mains filter with earthing, and only the safe voltage of 48 V direct current is fed to the machine itself; the machine is then joined to the computer with the supplied cable. The cutter is fixed in the collet chuck of the spindle and tightened with the key, and the workpiece is clamped in the universal vice with no protruding unsecured parts. After switching on, all three axes perform a calibration movement to the limit switches and the spindle returns to the zero point of the Z axis. The control program in G-code format is prepared or opened in the supplied software and loaded into the machine over the connection with the computer, after which the depth of milling per pass is set according to the material, larger for wood and plastic and smaller for metal, and the spindle speed is chosen according to the material and the cutter diameter.
During work the safety goggles from the set are worn, hands are kept away from the working zone while the spindle rotates, and the workpiece or the cutter is removed only after the spindle has stopped completely; in the event of any anomaly the emergency stop button is pressed. The machine is not left switched on unattended, and machining is not started without a workpiece securely clamped in the vice. After each session chips and dust are removed from the working zone, the guide shafts and the screws with a soft brush and a dry cloth, and the mains power supply unit is disconnected from the socket before cleaning; solvents, acetone and abrasive agents are not used on the body and the guides. Operating conditions are the premises of an educational institution at an air temperature from +5 to +40 °C and relative humidity from 40 to 60 % without condensate. Marking and operating documentation are in Ukrainian, the marking carries the trade mark, the model and a place for the inventory number, and the documentation comprises the passport with the warranty coupon, the operating instructions and the methodological materials. The service life is 5 years and the warranty period is 12 months from the date of sale.
