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cnc_machine_goliath [2014/03/13 19:08] – created thesaxmachinecnc_machine_goliath [2022/07/17 03:23] (current) swalde
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-CNC Machine Guidelines+=== Note: Goliath is no longer at the space.  The Laguna is a more capable replacement === 
 +[[laguna|Laguna]] 
 + 
 +=== 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.1394737695.txt.gz · Last modified: 2014/03/13 19:08 by thesaxmachine
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