Many designers use some kind of computer-aided design or CAD software to make 2D and 3D designs. A common one used by many people is Rhino (especially when used in conjunction with the Grasshopper plugin). Fusion 360 is a newer, easy to use, free complete CAD/CAM package. If you are going to learn any CAD software for practically any purpose (designing, engineering, fabrication, rendering realistic models, etc) it should be Fusion 360.
Fusion 360 is an Autodesk application that can do many useful things for designers. Whether you want to do something as simple as making cool looking 3D models to stress testing (finite element analysis) and even simulating the simple physics of designs and even milling them out or 3D printing them, Fusion 360 has you covered. It can also render realistic materials and surfaces and make animations of your working mechanical devices. Did I mention that it is free and there are tons of free online video tutorials and classes showing you how to use it with example projects? Oh, and so you aren’t reinventing the wheel (or other simple hardware) you can bring in models directly from McMaster-Carr who carry all sorts of nuts, bolts, gears, chains, etc. which can save you loads of time. This is my brain dump for getting started with Fusion 360 and using it with my CNC machine and my wife’s 3D printer.
Download Fusion 360 for free license. They have yearly licenses for hobbyist and I think even small business, or you can get a 3 year license for education.
Learning to use CAD:
At this point, there are two methodologies to use when creating parts in Fusion 360. If you have CAD experience already, you might be more comfortable drawing 2D parts then extruding them into 3D, etc. If this is you, then check out this free training class. The second methodology is sculpting. It begins with simple 3D shapes you can manipulate almost as if it were made of clay. This is great for 3D smooth shapes. Check out this great free training class for this methodology after taking the first section of this class. These two methodologies don’t replace one another, rather they compliment each other. You will eventually need both for complex designs, but start with whichever one is easiest for you so you can progress quicker. I personally love the “sculpting” mode.
Since on a CNC machine, the Z axis is the one you attach the router to, you will need to change the position of the Z axis in Fusion 360. Then set your preferences such that Z axis is the top axis. Within Fusion 360, click your name at the top right->Preferences. In the main window that pops up, about half way down, there is a “Top Axis” option that is set to Y, change this to Z and then “Apply” Now Z is the top axis like on your CNC machine. This will work for all NEW documents, but if you happen to have an older design or are importing someone else’s design, there’s a couple different ways to change the Z axis. The simplest method is to select the up-axis when you “setup the job” in Fusion 360. This is done when you are finished with your model design, and want to start creating the toolpaths.
Now, get into making some stuff. While Fusion 360 can do 2D and 3D designs and generate toolpaths for the CNC machine, there are lots of simpler (dumber) 2D workflows out there that are great such as Makercam.com or Easel from Inventables, etc. I’d use Fusion for more complicated 2D and 3D designs. For example, Easel won’t allow you to use a chamfer bit or V bit for engraving last I checked, but Fusion 360 will. This can make some amazing 2D designs.
You will notice that some of the videos tell you to delete certain lines in the generated Gcode from Fusion. This is mostly because it adds a “home” command and many DIY CNC machines don’t have homing switches. This command might tell your machine to go to the maximum extent of your machines to find the switches, but since you have no switches, it’ll end up messing up something. So many of the tutorials suggest removing the G28 (home) line from the Gcode Fusion 360 generates. If you have a smoothieboard controller, you should be fine to leave it in as long as you have set up your config files correctly.
How to set your origin to a different are of the design for milling. The best setup is one like the Othermill uses which ensures you never cut into your spoilboard. “Don’t spoil the spoilboard” is a great explanation of this method. I hope to make vids on how to in fusion 360 and real machine.
Can export to Othermill, or Smoothieboard, pocket NC, or other mill. Tons of options in the “Post Processing” menu.
You can simulate the milling process. When you do, the paths have different colors. A post on Autodesk’s forum cleared up what they mean:
Here’s my video of an example project I made. It is full of tips on stumbling blocks I came across.