UNIVERSITY OF LJUBLJANA - FACULTY OF MECHANICAL ENGINEERING LAKOS - Laboratory for Technical Cybernetics, Manufacturing Systems and Computer Technology 3D CNC-ENGRAVING MACHINE Lakos 150 USER MANUAL
Produced and assembled by LAKOS – Laboratory for Control, Manufacturing Systems and Computer Technology Faculty of Mechanical Engineering, University of Ljubljana Aškerčeva 6 SI-1000 LJUBLJANA Phone +386 1 4771 200 Fax + 386 1 2518 567 e-mail lakos@fs.uni-lj.si Technical specifications are subjected to change without notice.
Table of contents 1 Machine description, connection and start-up procedure ................................................................................... 4 1.1 Machine description .................................................................................................................................................. 4 1.2 Connection board.......................................................................................................................................................
1 Machine description, connection and start-up procedure 1.1 Machine description Lakos 150 is 3-axes milling machine enabling milling, engraving and drilling. Movement is achieved by three stepper motors, controlled by an interface. The machine positional resolution is 0,05 mm. The cutting process is performed by an serial engraver with the rotational speed range up to 20000 rpm. However, machine features enable usage of a professional spindle.
1.
Connect the EMC-CNC controller (PC) and LPT interface with the parallel cable. Connect power supply where necessary Do not switch power on until all appliances are interconnected Figure 3: Connection board at the machine pillar rear (the serial female connector is for LPT-interface, the parallel male connector is for future use). Figure 4: LPT-interface, front panel (On-green button, Off-red button) 1.4 Start-up procedure Turn on the PC and wait for Ubuntu Linux to boot, then log in.
By pressing the E-stop button ( ), the e-stop mode is turned off (keyboard shortcut: F1). Pressing the „Device On‟ ( for use (keyboard shortcut: F2). ) button on the right prepares the device WARNING: E-STOP button puts the machine in E-stop mode, however, in case of emergency the Emergency Stop button at the machine front should be used. Prior to operating, the device must be set to a starter position. Chapter 2.3 shows how this is achieved.
2 Device control 2.1 User interface EMC2 allows usage of three graphical user interfaces (GUI) types, namely AXIS, TkEMC, and MINI. Fig. 5 displays the AXIS interface, which is invoked by default. All GUIs have similar functionalities. To switch between them, the DISPLAY command in the .
Command line buttons of the AXIS GUI (from left to right): 2.
To achieve an incremental jog instead of continuous motion, the drop-down menu under “Home All” is used. Possible settings include continuous, 1.0000, 0.1000, 0.0100, 0.0010, 0.0001. The incremental jog units are millimetres. The spindle can be still or rotating. To switch between these modes, use “Stop” or . Prior to operation, the engraver must be switched on. The rotational speed of the engraver is set up by using a button on the engraver itself.
2.4 Offsets Offsets are used to synchronise the tool and a work-piece coordinate system. For example, offsets can be used to avoid defining a reference point during programming. The device can be moved to an arbitrary point, which is then set as an actual coordinate system. Click of the „Touch Off‟ button (keyboard shortcut < End>) opens a window, which may be used to set up the tool offset on the active axis in reference to the program.
2.5 Operating programs The program file types used for operating the device should be ngc and nc (program_name.nc). G code in use is defined in RS274. Program can be prepared in any text editor considering file extension. The program execution in Axis GUI is possible in Manual Mode and in TkEMC GUI in Auto Mode. To open a program any of following possibilities a) „Open‟ button, b) the File>Open dropdown menu, or c) the O key on the keyboard can be used .
3 Programming 3.
G90 G91 absolute distance mode incremental distance mode 3.2.2 M codes M0 M2 M30 program stop (resumed by clicking Resume program end program end and reset 3.2.3 Other codes F feed rate 3.3 Basic codes G0 – rapid positioning G0 X5 Y10 Z20.5– moves tool from current position to X=5, Y=10 and Z=20.5. G1 – linear interpolation G1 X10 Y15 F60 – linear interpolation (cutting movement) to point X=10, Y=15. Definition of feed rate is necessary, in this case 60 mm/min.
Usage of variables #120=100 – sets the value of variable #120 to 100 G0 X10 Y10 Z10 F#120 – rapid movement to point X10, Y10, Z10, federate being 100 mm/min, defined by the variable #120. 3.4 Program examples NC programs have the .ngc or .nc file extension. The usual program line is composed of the starting line mark and the consecutive commands. Example 1: N00 N05 g57 N10 g0 x0 y0 z10 N15 g0 z1 N20 g1 z-0.
Figure 7: Program 2 contour 16
4 LAKOS 150 engraver specification Dimensions Length Width Height 655 mm 440 mm 850 mm Working area, maximum travel length along each axis: X – 205 mm Y – 177 mm Z – 130 mm Feed rate from 0 to 600 mm/min. 3D linear interpolation Circular interpolation in three main planes: XY, XZ, YZ (G17, G18, G19) Length compensation (G43, G49) Driven by stepper motors and 5mm ball-screw spindles Positioning resolution: 0.05mm. Electrical engraver PROXXON– max. 20000 RPM; 100W Grip diameter 0.8 mm, 1.
5 Safety and maintenance SAFETY INSTRUCTIONS POSSIBLE DANGERS Rotating parts of the machine can injure the operator. Sharp and hot chips can cut or burn the operator or injure eyes. Unorganised and under illuminated working area may hinder efficient work. Untrained and unwise handling. BEFORE WORK Only trained and authorized personnel should operate the machine.
AFTER WORK Inspect the tool and remove it from engraver Clean the engraver and its environment. Press the off switch on the LPT interface. Shut-down the computer. Turn off the mains switch on the connection board.
6 Sources EMC2: V2.1 User handbook, 2007 (25 February 2007), www.linuxcnc.org http://www.linuxcnc.org/docs/EMC2_User_Manual.
7 Appendix 7.1 Electrical schemes 7.1.1 Charging scheme This scheme shows the electrical power supply and its distribution through the LPT interface.
7.1.2 Driver scheme The driver scheme describes the gecko interfaces connection to the stepper motors. The connection cable is included in the bottom of the schematic.
7.1.3 Gecko interface scheme The Gecko interface scheme shows the connection of the Gecko, emergency and home switches a port receiving signals from the EMC2 interface.
List of parts – LAKOS EAC Description: Lakos 150G 3D CNC engraving machine o Motor cable-ropes attached o Legs (2 pc. short – machine rear side, 1 pc. Long – machine front side) Proxon toolkit o Additional tools: Milling HM φ3 mm Milling HM φ2,5 mm Milling HM φ2 mm Power controller o Cables included: RS232 (DB9) Parallel (DB25) Power Controller computer (Pentium Dual Core E2140) o OS: Ubuntu Linux 6.
Unpacking – LAKOS EAC 1. Remove all computers, keyboards, mice, tools, cameras, and controllers. 2. Remove package side covers. 3. Both machines are fixed on the pallet: The machine front is screwed on a wooden holder by two M10 screws from the bottom. The rear side is fixed by two metal plates. 4. Unscrew the metal plates on the rear side. 5. Unscrew 2x4 +1 screws of the wooden holder fixing the machine front side. 6. This gives the access to the two M10 screws in the bottom, which must be also removed. 7.
