Why would I use free CNC software
You’ve built your 4 Axis hot wire foam cutting machine or 3 Axis router and now you need some CNC software to control the machine. I often get questions through this website from fellow hobbyist asking what software they can use to cut foam wings, fuselages or parts on their CNC router. Most hobbyists are prepared to pay a reasonable price but when you start adding up the cost of the machine in as well it soon adds up to a chunk of cash.
This article is an overview of what’s available to us hobbyist and then the follow-up articles will go into more details for each solution. It’s not an exhaustive list and I’ve picked out solutions which I think are suitable. If you know of any more let me know and I’ll include them.
There has been a bit of an explosion in hobbyist CNC machining over that last few years Partly due to 3D printers becoming very affordable and CNC routers from companies like X-carve. They have very easy to use software like Easel and Carbide for the Shapeoko. I haven’t included these two in this series because although very easy to use on their own routers you need to manipulate the g-code to work on others. Maybe a future article.
Example costs for paid CNC software
If you were to buy Mach3 or a Mach4 license at $175/$200 and the software I use for foam cutting DevWing Foam and DevFus Foam which cost $225, then you’re up to $400/€340/£300. I’ve always had good support from DevCad who supply the Foam software, which you may struggle to get with the free solutions, but sometimes it can be better than paid! So one question that comes up a lot is are there any free or low cost
Up until recently, I’ve always used paid software for my foam projects, not by choice but because there wasn’t much out there. On my CNC router, there are quite a few free options and some of them are very good. I’ve spent more money on software for my hot wire foam cutter than the actual machine itself.
When I made my first flying wing I’d say to people it’s either the cheapest wing I’ve made or the most expensive! For a little while, I’d only made this one wing so if you add the cost of the machine to the wing then it was damn expensive. But now I’ve made several wings and fuselages and its paying for itself now. Plus when you’re flying and people say where did you buy that from, you say “you can’t buy these I make them with my CNC machine”. I’ve had that several times and people ask me if I can make them one as well.
There’s an old saying in that you get what you pay for, and with CNC software that is sometimes true but surprisingly some of the free software is amazing.
The choices for 4 axis foam cutting software isn’t as extensive as 3 axis routers and those that are there tend to paid options. But there are a few free options now, more than a few years ago. Keep reading.
For CNC routers there are quite a few free options and some very good ones, so if you want to use a Windows OS then Mach3 or Mach4 may be all you need. If you can use LinuxCNC then all your software could be for free. LinuxCNC is a very good machine controller and you shouldn’t discount it. I know if you’ve grown up with Windows it can be a little daunting but it’s actually quite easy. All the details here on using LinuxCNC a CNC router and here foam cutter.
Benefits of Using Free CNC Software
One benefit of using free/open source software apart from the obvious cost saving is the community. If you get stuck there is usually a wealth of knowledge and people who are willing to help. You may even be talking with the developers and so you gain a better understanding of your system. If you just do a Windows, Next->Next->Next install you don’t really learn much and when it doesn’t work it can be very frustrating. Don’t get me wrong there is some good Windows CNC software out there but troubleshooting can be tricky sometimes.
All too often the cost of CNC software turns people off the idea, but there are solutions available. I’ve retired from work now and have time to try out the free options, some I’ve already used, and I’ll pass on what I’ve learnt. I will be trying out solutions for 3 axis routers and 4 axis hot wire foam cutters.
But first, let’s get some basics out of the way. If you’re new to all this then it may help. I know when I started these 3 letter acronyms weren’t that clear to me. If you’re an old hand at this then skip the next section
CAD/CAM and Machine controller
Before we discuss the options an understanding of CAD/CAM will help because some solutions do both and others do one or the other.
CAD is Computer Aided Design. So in our context, this would be the software that you would design your foam wing cores or wing ribs for a CNC router.
CAM is Computer Aided Manufacturing. This takes the design and controls the manufacturing process. So this would generate the G-Code from our design. G-Code is the instruction we send to the controller to move the stepper motors to control the path of the hot wire or router bit
Machine controller – This is the software that takes the G-Code and via the hardware, controller
Software for Foam Cutters – 4 Axis
Jedicut is quite unique in that it can do CAD/CAM and Machine Controller, but only on Windows. If you want to use it as a controller as well you’ll need a computer with the old parallel or an adapter card Check my post on the parallel port You need to add the aerofoil data points, but there are lots of free sources for this. This is one of the main ones http://m-selig.ae.illinois.edu/ads/coord_database.html Get a DAT file, something like the clarky.dat to load into the airfoil section.
JediCut is French software and there are a few translations missing but its not to difficult to work out. There are two ways to use the software. Connect your PC’s parallel port to your controller and let JediCut do everything. Or use the g-code plugin option to just get the G-code generated and then load into LinuxCNC or Mach3. Mach 3 will do 500 lines of g-code for free. Sounds a lot but you’d be surprised how many lines of g-code it takes to make a part when it reaches 500 it just stops.
I prefer to use the g-code plugin as the parallel port option doesn’t work on my controller, see video below.
For a free program, it does a pretty good job but it needs time to learn it and is not as polished as the paid options.
Wire cutter Wings in Gcode
This is from http://swarfer.co.za/rc/wire/index.php and is a CAD/CAM option. This one requires you to register to get the g-code but David has rewritten the code in Python and can be downloaded for here https://github.com/swarfer/winggcode It will work on LinuxCNC from the Axis interface and includes washout in the new version. David has kindly sent me details and how to run the code as an add-in for LinuxCNC. It will run on windows but you will need the Python interpreter which is free from https://www.python.org/downloads/
Software for 3 Axis Router
This is a CAM solution and takes a file generated by a CAD program and outputs the g-code. It is written in Python so it will work on Windows, Linux and Mac. You can download from here https://sourceforge.net/projects/dxf2gcode/ There are many free CAD programs that save in DXF(data exchange format). The format was originally designed by the makers of AutoCAD and has become an industry standard. My favourite free 2D CAD program is DraftSight
On LinuxCNC you can add it as a plugin in your ini configuration file and it will post the code straight into the interface ready for cutting
A CAD/CAM solution that uses a plugin for Sketchup. This will run on Windows and Mac. It was originally developed for the PhlatPrinter a very interesting design, check it out here https://openbuilds.com/builds/original-phlatprinter.95/ It can be used for 3 axis routers by creating a config file with the right parameters. David the Swarfer who has developed the 4 axis wing g-code above is very involved in the development and has produced several excellent videos, check out his channel on YouTube https://www.youtube.com/user/swarfer42
Before you can use the plugin you’ll need to learn Sketchup which is a 3D modelling program, just the basics. I use Sketchup and it really is very powerful but very easy to use. Once you have the basics then follow David’s video’s on installing and using the plugin. I’ve used it and it does a pretty good job and is quite easy to understand.
This is a very powerful program which comes from the makers of AutoCAD which runs on Windows and Mac. Get it from this link https://www.autodesk.com/products/fusion-360/free-trial and there is an option for the hobbyist. It has a fairly steep learning curve, but once you’ve grasped it you’ll probably use it all the time. Its available to hobbyist for free as long as register every year. It includes many features and does CAD/CAM plus some advanced modelling features. I’ve used it for making motor mounts on my OX CNC router and a spinner for my Focke Wulf 190. I was then able to export the STL file into the slicing software Cura. I then used my Anet A8 printer to produce it, check out the video.
As you can see there are solutions for both 3 and 4 axis machines. Which one you use really depends on how complex your projects are. For 3 axis routers Fusion, 360 will do all you need plus a lot more, but it’s a steep learning curve. It well worth the effort. I use it for all my router and 3D printing projects. SketchuCam and dxf2gcode are somewhat easier to learn and may do all you want. For foam cutting, the paid options are more polished and perhaps a little easier to learn but if you are prepared to put the time to lean the software then you may have all you need. In future articles, I’ll try each option and produce an article/tutorial on their use.
Free CNC Software Articles
This is the planned release dates of more detailed articles I’ll produce for the 2018.
- Getting LinuxCNC working on the OX CNC router
- Using LinuxCNC for hot wire foam cutting and WingGcode
- JediCut for 4 axis foam project