ABRA CNC ENGRAVER 05

Transcription

1 ABRA CNC ENGRAVER 05

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3 Table of Contents BILL OF MATERIALS... 4 INTRODUCTION ABRA CNC MACHINE SAFETY CONSIDERATIONS MATERIALS REQUIRED HARDWARE DESCRIPTION ASSEMBLY INSTRUCTIONS ELECTRICAL ASSEMBLY CONTROLLER BOARD MOTORS MECHANICAL ASSEMBLY GRBL CONTROLLER SOFTWARE INSTALLATION FIRMWARE LOADING SETUP AND TESTING CANDLE SETUP AND CALIBRATION BASIC CONFIGURATION SETTING END LIMITS AND HOMING CALIBRATING MOTOR STEPS MILLING FILE CONVERSION FOR CNC GCAM SVG to G-CODE FILE UPLOAD (CANDLE) AXIS CONFIGURATION

4 BILL OF MATERIALS USB to Mini USB Cable CNC Controller Board Zip Ties 220mm V-Slot Railing x2 300mm V-Slot Railing x5 330mm V-Slot Railing x2 M8x320mm Lead Screw Rod M8x340mm Lead Screw Rod M10x330mm Smooth Rod x2 M10x340mm Smooth Rod x Corner Brackets x 16 Aluminum Motor Brackets x2 M5\M3\M2.5\M2\M1.5Allen Key M5x10mm Screws x60 M5 Washers X20 M5 Nylon Washers x4 Aluminum Heatsinks x3 M5 T-Nuts x60 M3x6mm Screws x8 Springs x2 M8 Brass Flange x2 M8 Couplers x2 T-Nut Screws/Washer/Wing Nut x4 Brass Couplers x1 7K RPM DC Motor Z-Axis Module + Stepper Motor M10 Smooth Rod Clamps x8 DC Motor Connector Drill V-Bits M10 Pillow Blocks x4 M8 Lead Screw Pillow Block M8 Lead Screw Pillow Block Y and X Stepper Cable to Controller x3 Corner Supports x2 Stepper Motor x2 CNC Table Power Supply 0.68µF Capacitor M6x10mm Screw x10 M6 T-Nuts x10 4

5 INTRODUCTION This mini CNC (Computer Numerical Control) engraving machine is ideal for use on nonmetal materials such as plastics, wood, acrylic, PVC and PCB. The machine is low profile, lightweight and easily connects to your preferred GRBL CNC software via mini USB. This kit is ideal for hobbyists interested in rapid prototyping and manufacturing. The CNC is a 3-axis removal machine. This ABRA Kit includes all the necessary equipment and instructions to be ready for operation within a few hours. GRBL is a high-performance, low cost alternative to parallel-port based motion control CNC milling. The system runs on the Arduino IDE Atmega 328 platform (Uno, Duemillanove, Nano) in C code, however G-code and M-code commands can also be sent to the machine's EEPROM directly. GRBL has full acceleration management techniques using look-ahead algorithms. The controller will look up to 18 motions into the future and set its velocities accordingly to deliver a smooth acceleration and jerk-free cornering. The CNC Machine is equipped with many failsafe measures and error feedbacks to protect the machine and user to allow for easy debugging procedures. The machine is ready-to-use but can be easily adjusted on-the-fly. Advanced users can directly modify the firmware and configure preferences. 5

6 1-ABRA CNC MACHINE 1.1-SAFETY CONSIDERATIONS The use of this machine may pose many safety risks that must be addressed: Always wear the appropriate eye protection, breathing mask and ear protection needed for each job. Always inspect the CNC machine for any visible problems before each operation. It is recommended to test each motor axis before beginning a mill. For the safest operation, store the machine in a well-lit, well ventilated work space. It is a good idea to have an open space surrounding the machine, so it does not become cluttered. The CNC machine will be loud and will produce a lot of shaved material. Be sure to keep the machine in a space that can accommodate the sound and dust. Always keep the machine clean and dry before and after each job. The CNC machine may vibrate and move during a job. If possible place rubber feet or clamp the unit down to prevent skidding. The CNC spindle spins at a very high speed with a very sharp bit attached to it. Never place your hand or body part near this part while it is activated. For assembly and calibration, it may be wise to slow down the motor or unplug it entirely. The CNC machine is plugged into a very strong power supply and will draw a lot of current in use. Always be careful that the power supply is safely connected with the jack connected to the CNC controller board first prior to connecting to a power bar or wall outlet. The power supply may pose a fire threat if misused. Always consider electrical protection when using the CNC machine. Try to avoid plugging multiple tools into an outlet at the same time. Always unplug from the wall outlet side before disconnecting from the controller board. Do not manually move the motors when they are off. This can produce a reverse current and damage the CNC controller. Always unplug the motor connectors before manually moving them. Never leave the CNC machine unattended during a job. Understand the level of difficulty involved with this machine and understand the machine's intended applications and limitations before beginning. Refer to this manual or other references before attempting a repair or adjustment. See additional document for In-depth Assembly Guide. 6

7 1.2-MATERIALS REQUIRED This kit comes with everything you need to get the CNC machine functioning. You must have a computer capable of supporting the Candle, GCAM and Arduino software. Tools Suggested for Assembly: Precision ruler or caliper Marker Test board for calibrating Mill. Loctite screw thread-locker Tweezers Soldering Iron 1.3-HARDWARE DESCRIPTION CNC Machine: Weight: LBS (5.8kg) 340mm (w) x 330mm (d) x 310mm (h) Limitations: Maximum carving thickness: 30mm (Varies on bit used) Head travel dimensions: o X: 24cm o Y: 18cm o Z: 4.5cm 2-ASSEMBLY INSTRUCTIONS An Online Video Guide is available for assembly. We recommend beginning the assembly by testing the electrical components and board. We can test each part individually and determine if any need replacing or servicing. This facilitates debugging and calibration later. You can mount the machine frame and then install the working hardware. To properly test the board and motors, skip to section GRBL CONTROLLER SOFTWARE, then return to ELECTRICAL followed by MECHANICAL assembly sections. 7

8 2.1-ELECTRICAL ASSEMBLY Z-AXIS X-AXIS Y-AXIS Figure 1- Electrical Assembly CONTROLLER BOARD The controller board is where all the hardware is connected. The power and programmer cables are connected as well as the motors and drivers. Connection is done as shown below in Figure 3. Figure 2-Board Diagram 8

9 (Note: We observed the maximum voltage the motor and controller board can take is 36VDC. We also noted as the voltage supplied to the motor is not constant and alternates causing reduction in performance. To fix this issue we suggest to solder a capacitor at the spindle motor. We provide the capacitor in the kit, if you wish to improve the quality of your mill, you will be required to solder them, and polarity is not of concern, since the capacitor is bi-polar.) MOTORS Motors and motor drivers are connected to the board and mapped to the controller pins depending on their axis. Motor direction can be inverted in the software and firmware later. The stepper rate can also be adjusted in the software; however, it may be useful to tune the motors from the potentiometer on the driver. (Loosening results in more current and larger step, tightening will result in smaller step. Please note this has already been fine-tuned to work straight out of the box). 2.2-MECHANICAL ASSEMBLY Once we are certain all the parts are included in the kit and function correctly, we can proceed to the frame assembly. The CNC Machine s precision is determined by the precision of its assembly. To reduce vibrations, be sure to tightly fasten each piece and perhaps use LocTite thread-lock for the screws. Follow the link for video demonstration of the frame assembly or refer to the additional manual. 9

10 3-GRBL CONTROLLER SOFTWARE In this step, we establish connection to Candle CNC to test our motors and load our milling files. Using this software, we can also issue G-code commands to modify the machine s EEPROM firmware. To properly install and operate the CNC Machine kit, Arduino software and libraries must be installed. Some computers may also require the CH340 serial drivers to be installed. Please note, that some laptops may not be able to support this CNC Machine. We recommend using a desktop computer with USB 2.0 port if possible. 3.1-INSTALLATION Several different software options are offered for running the CNC machine. The ABRA Kit uses Candle. Different users prefer different versions. Usually the code is opensourced and is updated frequently. The firmware is also available for download. Become familiar with the versions and decide which is best for you. Figure 3- GRBL Controller Software Candle: [MUST BE ON GRBL FIRMWARE 1.1f] Firmware 1.1f: Arduino: CH340 driver: GCAM: 10

11 3.2-FIRMWARE LOADING Your CNC Kit should have already come with firmware 0.9j installed and you should not need to re-upload it. If your machine is acting incorrectly or you wish to factory reset your kit, simply download the firmware from the link above, save it in my documents>arduino>libraries as grbl folder with the content inside and load it onto the board using the Arduino software (IDE). There are Three methods to programming the board. Target Link: Visit the target link suggested above, and click on Attachments to download gettingstarted.zip Method 1: After installing Arduino IDE, Connect the board using the USB cable to the computer. (Please ensure you have no motors or external power connected to the board.) Open Arduino IDE and select the following settings: o Tools>Boards>Arduino Nano o Tools>Processor>ATmega328 o Tools>Port>Whichever com port this board is assigned Click upload to flash firmware or Serial monitor for a pop-up window to communicate with the board. Set the baud rate to to see the screen printout GRBL Version #. Method 2: If you cannot program and get the error message avrdude: stk500_getsync() attempt this second method. Open Arduino IDE and select the following settings: o Tools>Boards>Arduino/Genuino Uno o Tools>Port>Whichever com port this board is assigned Click upload to flash firmware Method 3: Should method 1 and 2 fail, try this final step before consulting for support. Open XLoader software. Press icon to locate hex file to program to the board. Select GRBL_V0.9J.hex. Select as Uno(ATmega328) and the assigned comport with a baudrate at Press upload. If the system freezes and you observe on the controller board the LEDs do not blink, simply disconnect the cable and reconnect the cable. o The software will automatically close. o Re-open XLoader and set as Nano with the same Com port and baud rate. Should all three methods fail, feel free to contact the vendor. 11

12 3.3-SETUP AND TESTING In this section, we establish connection with the GRBL Controller software host. We must connect on the appropriate port and set the correct Baud rate. Baud Rate: If the motors, board and power supply have been installed we can connect the unit and test the system. If the Arduino drivers and software are up to date, the CNC Machine should be recognized automatically as it is plugged in. First, we set the machine s communication baud rate and port so we can send files and modify parameters. Once connection is established, the parameters are displayed. We can then unlock the machine and move the motors for calibration. 12

13 CANDLE Figure 4 - Candle port connection (Note: If you cannot connect and have the same status message as shown in figure 4 under console section. Close any software that is communicating with the board such as Arduino or any other CNC software.) 13

14 Figure 5- Candle Unlock (Note: Alarm lock will only occur if you use Hard limits and print in the console the warning message. To reset you use this button or type $X in the window and press the paper airplane to send to the controller.) 14

15 Figure 6- Motor Movement (Note: Jog allows movements, if we press up the table should move outwards and inwards for the bottom button. Left and right will move left and right respectively. The white button will move the z-axis up or down respectively. Movements are done in mm and are set so accordingly to the firmware settings. From the dropdown menu choose the step or distance to travel by and feed for the speed to travel at.) Observer Y + X RIGHT > X LEFT < Y - 15

16 Figure 7- Zeroing before Milling (Note: Both buttons in one rectangular box are used for zeroing Z-axis and XY-axis. This button is important as you must zero the machine coordinate before every mill project you want to send. Home feature can be used once the coordinates are zeroed to return back to that zeroed point. You can verify if the location is zeroed by looking at the work coordinates to see 0 on all three dialog boxes. Z-axis must be zeroed when the drill bit is touching the material you wish to work on). Observer Origin X-axis 16 Y-axis

17 Figure 8- Spindle Speed and Enable (Note: By clicking on the three lines you can expand options for the spindle and set the speed to for a speed of 7000 RPM. By clicking on the spiral icon, you can activate the drill motor and it should start spinning. You will do this action every time before you send your file to mill!) 17

18 4-SETUP AND CALIBRATION Your CNC machine is almost ready to use. At this stage, we should have the entire frame assembled, the power properly connected, established connection to the GRBL software and control of each motor axis. This step will show us how to fine tune the machine for precise milling. The objective is to configure the motors to their maximum working range at their optimal step rate. Before calibration, we recommend attempting a default mill without the Drill bit. This mill will most likely be unsuccessful but will serve as an important guideline for calibration. If the milling job succeeds, congratulations you are one of the few users who were lucky enough not to need calibration! Enjoy your new CNC Machine. Proceed to step MILLING, observe the errors and results then return to this step if needed. 4.1-BASIC CONFIGURATION Enter commands directly into the Candle console. Figure 9- Candle G Code Command Console SETTING END LIMITS AND HOMING This kit does not come equipped with hard end stop limit switches. We must control the spacing and dimensions using soft limits. In hard limit mode, the machine will send all its axis to maximum position until they trigger the limit switch (not equipped). Instead, our soft limit mode uses the dimensions of the table and known relative distances to stay within bounds. 18

19 Using GRBL Control- Axis Control Menu, move the X and Y motors to their minimum position (0 position). Move the Z axis to its minimum position. Click Zero Position (or Zero XY and Zero Z ). This command has stored these positions as zero in the machine s EEPROM. (See figure 7) This step can be repeated if necessary. Now that the zero positions have been set, we can configure the maximum positions. In GRBL Control enter the following commands *ignore comments in [ ] : $0 = 10 [step pulse, usec] $1=25 [step idle delay, msec] $2=0 [step port invert mask: ] $3=5 [dir port invert mask: ] $4=0 [step enable invert, bool] $5=0 [limit pins invert, bool] $6=0 [probe pin invert, bool] $10=1 [status report mask: ] $11=0.010 [junction deviation, mm] $12=0.002 [arc tolerance, mm] $13=0 [report inches, bool] $20=0 [soft limits, bool] $21=0 [hard limits, bool] $22=0 [homing cycle, bool] $23=0 [homing dir invert mask: ] $24= [homing feed, mm/min] $25= [homing seek, mm/min] $26=250 [homing debounce, msec] $27=1.000 [homing pull-off, mm] $100=800 [x, step/mm] $101=800 [y, step/mm] $102=800 [z, step/mm] $110=5000 [x max rate, mm/min] $111=5000 [y max rate, mm/min] $112=800 [z max rate, mm/min] $120=10 [x accel, mm/sec^2] $121=10 [y accel, mm/sec^2] $122=10 [z accel, mm/sec^2] $130=200 [x max travel, mm] $131=200 [y max travel, mm] $132=200 [z max travel, mm] 19

20 4.1.2 CALIBRATING MOTOR STEPS This step is crucial for a precise milling. This tuning ensures that the motors travel the exact distance they are commanded. Repeat this procedure for each X,Y and Z axis motor: Send motor to its zero position. In GRBL Control, command the motor to move 10 units. Accurately measure the actual distance travelled. Calculate the new step by: o New_step = Current_step * (commanded_step / actual_step) o Ex) New_step = 800 * (10/10.32) = o The default step for each motor axis is 800 o Your results should vary from ours but we determined: X_step = Y_step = Z_step = o Repeat the steps and measure, iterate the calculation until the value stabilizes to obtain an optimal precision. To save these values in the machine s EEPROM, enter the following commands: o $100 = (use your values) o $101 = o $102 = This step can always be repeated and reverted, but generally doesn t need to be done once it is saved. 5-MILLING Unlike 3D printers which are additive machines, CNC Machines are removal machines. 3D printers operate in the positive direction axis frame, where CNC machines operate in the positive and negative Cartesian planes. Before each print, we must convert and upload our file then setup our axis. 5.1-FILE CONVERSION FOR CNC If this is your first mill, we recommend finding a sample file online that is already formatted (.nc). Otherwise, there exists several software that can convert a CAD design into Gcode instructions. You can choose from the list below. Sketchup Conversational CNC Scan2CAD GCAM (Highly Recommended) Alternatively, you can access a template file from our website under attachments for this product! 20

21 5.2- GCAM SVG to G-CODE This section is designed to simply show you how to convert SVG into NC for you CNC Machine. Download the SVG image you wish to mill. If you have a PNG or JPEG, they must be converted into SVG as SVG is a vector image that has coordinates for each line. Feel free to watch online tutorials using inkscape (a free software) Once you have the desired SVG image, open GCAM as new project. The settings in new project will be the following: Project Name: [give any name you want] Base unit: mm Material type: [foam, plastic or wood] cannot do [steel or aluminium] Material Size: [length, width and depth in mm] If you want to cut through set the depth height, if you want to engrave set a depth smaller than materials actual thickness. Material Origin: depends on if you want to cut the material from corner or center [recommend corner as 0 0 0] Traverse height (Z): 1.27 End Mill: T05 0.2mm v-tip Machine: Taig Click File > Import SVG paths Select the image Once imported on select the template order on the bottom by left clicking to highlight it. Edit by scaling, rotating or transforming the object on the given workspace until satisfied. You may need to resize the coordinates, if you svg was larger than the material length. Click Edit > Project Settings to do so. You cannot change the depth, this requires creating a new project. After completion, select Render > Final part to see the final version of the object. After final verification, click File>Export G-Code Export G-Code as the following settings: Format: EMC Drilling Using: Canned Cycles (G8x) Pocketing Strategy: Traditional 3D raster Click apply and save as your preferred name with.nc as the final extension. 21

22 5.3- FILE UPLOAD (CANDLE) Figure 10- GRBL 3.0 File Upload 5.4- AXIS CONFIGURATION Once the design file has been converted and loaded, we attach the material to the plate for milling. For best results, try to centre the material on the plate. From GRBL Controller, move X and Y motors to approximate centre of material Zero these axes. (See Figure 7) Lower the Z motor until the spindle just barely touches the plate and zero the Z axis. Start the spindle (See Figure 8) Click Send and monitor the mill. 22

23 Figure 11- GRBL 3.0 File Send It is a good idea to perform a dry run before starting your mill. Set the Z Axis and spindle higher so that it hovers above the board without touching it. Then start the mill and observe if any part of the job goes out of bounds. (Note: Try using your mouse by right-clicking and drag on the window where the object is shown, you will notice the depth and layers to milling an object.) 23