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cnc_machine_goliath [2014/03/13 19:12] thesaxmachinecnc_machine_goliath [2022/07/17 03:23] (current) swalde
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-==== Basic Overview ==== +=== Note: Goliath is no longer at the space.  The Laguna is a more capable replacement === 
-  * Use favorite CAD program to generate a vector file (DXF, EPS, PDF, etc) +[[laguna|Laguna]]
-  * Load CAD file into a CAM program (Aspire, MeshCam) +
-  * Settings+
  
 +=== CNC Training ===
 +
 +== Safety and Basic info == 
 +  * Always have protection
 +  * Eyes
 +  * Ears
 +  * Loose clothing should not be worn
 +  * Hair tied back and out of the way
 +  * If you notice anything strange with the machine DO NOT USE IT
 +    * Notify thespace@sktechworks.ca
 +  * Be aware of where the big red button is
 +    * Pushing the button will stop the current job from processing 
 +    * It will not stop the router
 +    * turn off the switch for that
 +    * turn off the switch for cnc power
 +    * notify thespace@sktechworks.ca
 +  * Be aware of all the different ways you can shut off the machine
 +    * Safety should be your number one concern
 +    * You can always fix or redo a CNC job
 +    * Fixing a broken face is harder
 +
 +=== Materials recommended for CNC ===
 +== wood ==
 +  * hardwood
 +  * softwood
 +  * composites - MDF, OBS, etc
 +
 +== plastics ==
 +  * Be aware that plastics will melt if feeds and speeds are not set correctly
 +  * Polycarbonate
 +  * ABS
 +  * Acrylic
 +  * HDPE, UHMW
 +  * etc
 +
 +== Phenolics ==
 +  * G10, FR4, Garolite
 +
 +=== Materials not recommended for CNC ===
 +== Metal of any sort ==
 +* In theory the large CNC has the capability but it is not recommended
 +* Please use the Sherline for small metal parts
 +* Anything larger contact an external machine shop
 +
 +=== Make sure your work material is secured ===
 +  * This ensures your safety and those around you
 +  * Material that is not properly secured to the work surface has the potential to be ejected by the machine and injure anyone in the vicinity
 +
 +=== File Formats ===
 +  * Recommended file format from vector software is DXF
 +  * Depending on the CAM software it may be able to accept other formats
 +  * CAM software and GCODE conversion
 +  * SK Techworks has an art license for MeshCAM
 +  *Aspire is installed on the computer at Techworks
 +  *There are many other paid and free solutions out there
 +  *We will be going over Aspire
 +
 +=== Aspire ===
 +  * Aspire is CNC CAD/CAM package that has the ability to generate GCODE output for 3D carving and 2D profiling
 +  * Aspire can accept multiple vector file formats including STL, DXF, OBJ and others
 +  * The workflow for Aspire can be separated into two parts:  
 +    * Importing/creating the vectors and setting up the toolpaths
 +    * Importing/creating Vectors
 +  * When you start up Aspire you can either start a new job or open an existing one
 +    * in our case we want to start a new file
 +  * you will be greeted with a screen asking for the dimensions and type of material
 +  * there is also a section asking what the zero position is for the machine
 +  * select the top of the material for z-axis zero
 +  * I also recommend using the center point of drawing for x-y zero as it is simpler for lining up a job on your work piece - more explained later
 +  * **Please note the the long axis on our CNC is the x-axis**
 +  * If you have already generated your vector output you can just import the file by going to File->Import->Import Vectors
 +  * This is the workflow for 2d profiling
 +  * If there is an interest in 3D Carving I can go over this at a later date
 +  * After you have imported your vectors you then need to ensure that the vectors are closed
 +    * vectors that are not closed will result in unexpected toolpaths when we try to generate them
 +  * Once you have fixed your vectors you can then resize and position them as you like on the material
 +
 +== Creating Toolpaths ==
 +  * Once you have your vectors in place it is not time to create the toolpaths
 +  * This is how the CAM software will generate the GCODE for the CNC machine to run
 +  * On the top right of the program there will be a tab that contains all the controls for creating toolpaths
 +  * The operations we are interested in for 2D profiling are: 
 +    * profiling
 +    * drilling
 +    * pocketing
 +
 +== Profiling ==
 +  * This operation will cut out the shape of the vector you want
 +  * in the case of a circle let us say a generated toolpath will cut either on the inside, outside, or on the desired vector depending on the effect you require
 +  * It is important that the vector is closed when trying to do inside and outside profiling.  An unclosed vector will net an unexpected toolpath
 +
 +== Drilling ==
 +  * This is pretty self explanatory
 +  * One thing to note is this operation will only work on properly generated circles
 +  * some vector softwares will output a circle as a series of lines
 +    * while the end result resembles a circle it does not contain the same information
 +    * mainly where the circle is located
 +    * the problem here is that if you were to try to generate a toolpath on such a circle, Aspire will ignore it as there is no centerpoint to locate and drill
 +
 +== Pocketing ==
 +  * This operation will clear the area enclosed in a vector
 +  * for example if you have a circle and you do a pocket operation on it you can make a bowl or cup.
 +  * again it is important to ensure your vector is close so that the generated toolpath comes out as expected
 +
 +== Feeds and speeds, endmills ==
 +  * When generating GCODE with the CAM software, it takes into account the physical start point, endmill properties, feedrate, and speed
 +  * The physical starting point should already be set when you defined your workpiece properties.  If anything has changed you can access them through the edit menu
 +  * endmill properties are accessed when you have chosen a toolpath operation to perform
 +  * once you have selected a toolpath you then need to select the tool you wish to perform the cut
 +  * If a tool is not available in the default list you can create a new one to suit your needs
 +  * At the point you are accessing the endmill properties you can also change the feedrate and speeds
 +      * feedrate refers to the rate at which the endmill travels while cutting.  I believe the default is inch per minute (IPM) for the large CNC.
 +      * Speed refers to the spindle speed measured in revolutions per minute (RPM)
 +      * Feeds and speeds are a very important factor in the success of your job.
 +  * correctly set feedrate and speed will yield great finish and longer tool life
 +    * as a rule of thumb the plunge rate should be set to ½ your feed rate
 +    * pass height - which is the distance your endmill plunges into the material to perform a cut- should be a maximum of ½ the tool diameter
 +  * The CNC is capable of doing 100 IPM rapid movements but doesn’t like cutting at that speed depending on the material
 +    * 50 IPM is a good starting point for wood
 +  * Mach3 has the ability to dynamically change the feedrate during a job so you can start a job slow, then speed it up as you get to know the material properties
 +  * as the spindle is technically a tile router, it is not controlled by the CNC software.  So speed is manually set with the dial.
 +  * setting the speed too fast and feedrate slow will result in burning or melting
 +  * setting the speed to slow and feedrate fast will result in breaking
 +
 +=== Mach3 software ===
 +  * How to load GCODE
 +  * Keyboard Operations
 +    * Jogging the axes
 +      * the arrow keys control the x and y
 +      * pgup and pgdn control the z
 +    * rapid
 +      * shift
 +    * fine tuning
 +      * ctrl
 +  * emergency stop
 +    * big red button
 +    * esc key
 +  * setting feeds and speeds
 +  * Run the Job
 +
 +=== Basic operations ===
 +  * Power to the machine
 +  * power to the router
 +  * big red button
 +  * fan power for gecko
 +  * Tool Changing
 +  * Securing material
 +  * zeroing the machine
 +  * clean chips
 +  * Leave the machine in a state where someone else can use it with minimal setup
 +    * don’t leave your chips for someone to clean up
 +    * don’t leave your endmills in the router
 +    * don’t leave scrap material or custom sacrificial board on the machine
 +    * scrap material goes in the bin
 +    * if the bin is full, fucking empty it
 +      * we pay monthly for loraas even if we don’t use it
 +      * so we might as well use it
 +
 +==Fusion 360 Toolpaths==
 +I nice formatted tutorial of how to setup a job in Fusion 360
 +[[http://evanandkatelyn.com/2018/01/fusion-360-cam-tutorial-for-cnc-beginners/]]
 +
 +{{:Techworks.zip| Fusion 360 Post Processor}}
 +
 +Update: the following G28 thing might actually not be necessary.  Before setting the origin on the workpiece, move the spindle to a safe location above the workpiece.  Then, click "Ref All Home."  If you do this, that location will be the "Home" position that G28 goes to.
 +
 +This is very, very preliminary, but critical:
 +DISABLE G28.  If you leave G28 enabled, the machine will rapid to a bad place.  If you are lucky, it will only break your bit.  If you are not lucky, you will break the machine.  This has already happened once.
 +
 +DISABLE M6.  I'm not sure if this actually causes problems, but we don't have a toolchanger, so telling the machine to pick up a tool is pointless.
 +
 +==Feeds and Speeds Resources==
 +Onsrud has some good charts for chipload of various materials.
 + [[http://www.onsrud.com/xdoc/feedspeeds]]
 +
 +Once you know your chipload range, there are lots of online calculators to help you calculate RPM and feedrate.
 + [[http://www.monstertool.com/monster_tool_calculators.html]]
cnc_machine_goliath.1394737977.txt.gz · Last modified: 2014/03/13 19:12 by thesaxmachine
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