In this article, I’ll discuss 4 software solutions can be used for CNC Foam cutters that I’ve used with the pros and cons. With this information, you should be able to decide which one is best for you.
CNC Foam cutters are usually 4 axis machines with each one moving independently. So if we are creating a tapered wing each axis has to follow a cutting path that is different from the other axis but is synchronised. That means hot wire must exit the wing profile at the same time even if the root and tip are different sizes.
These are the 4 solutions:-
- DevCNC Foam
- 4 axis GRBL
This is the most popular for hobbyist and is very good. I started with Mach3 several years ago. You can run 500 lines of g-code for free but after that, you need a license which is $175. It’s possible to do some cut jobs in 500 lines but I haven’t found many.
Mach3 is windows only and was originally designed to use the parallel port that we used for printers. That port has long since been discontinued on computers but there are still many controller boards available.
So if you have an old desktop kicking around with a parallel port then it’s a good option. I still use Mach3 like this and it never failed me. The only caveat is that you need to use Windows 7 or XP 32 bit with the parallel port driver.
My old desktop PC is not connected to the internet and I’ve turned a lot of unnecessary services off. It has no antivirus software and no need for updates. It only runs mach3 and nothing else. I get the g-code on by a USB thumb drive.
You can use Mach3 on more modern computers but you will need a specialized USB adapter.
I have a post on my website showing several options for Mach3
LinuxCNC is a free alternative to Mach3 and is very good and still in development. It has configuration options for foam cutting which gives a better display. I’ve cut many wings with it. The only issue with using LinuxCNC is that it doesn’t work with USB so you are limited to the old parallel port or specialized Mesa add-on cards. Which can be a bit tricky to set up.
I have videos and posts on the website that show how to get LinuxCNC up and running.
4 Axis Hardware for Mach3 and LinuxCNC
Mach3 and LinuxCNC will require a controller card to drive the 4 stepper motors. Here are a few suggestions
DevCNC Foam is one of the newer offerings and works really well on a variety of controller boards. I use it on an Arduino Mega with a RAMPS 1.4 board. It’s not free and cost €60 but you have support.
You can download it and run up to 400mm of G-code total movement to check your hardware works OK. It even uploads the correct firmware for you so you don’t need to use the Arduino IDE or a loader to install the firmware.
The one big advantage of DevCNC foam is that it’s specifically designed for foam cutting. Whereas the previous Mach3 and LinuxCNC are general purpose.
4 Axis GRBL
This Arduino based 4 axis GRBL controller is a fork of GRBL originally for 3 axis which is free and works well, but it has a few limitations.
The main one being it doesn’t support the G93 feed rate mode. It can’t use limit switches. But these are not show-stoppers and I’ve made several wings using it. My video series on YouTube shows how to build a USB Foam Cutter using this software.
So which one would I recommend?
All of them, they all work well. The one you chose really depends on how much you can afford, skill level and intended use.
CNC can be very addictive and if you want to do some CNC routing as well then Mach3 and LinuxCNC are good choices and if you are on a budget and have an old desktop kicking around LinuxCNC is a great choice with a parallel port controller.
Configuring Mach3 and LinuxCNC can take a bit of effort but is well documented I have several articles on the website for both.
If you want almost a plug and play option then DevCNC Foam is probably your best option. Just connect it to one of the supported boards and it will upload the correct firmware. Just some calibration of the steps/mm and you’re up and running.
The GRBL 4 axis option is the cheapest option for USB and gets the job done. But you may need to spend more time configuring and testing. I have it fully documented on the website with a video series explaining how to get it working.
You will need to test speeds and feeds on more complex wings that have a big difference in the root and tip size because G93 doesn’t work on this board and no limit switches.
What is G93
G93 is a feed mode recommended by DevCad for DevWing Foam and DevFus Foam. For straight wings, it doesn’t matter too much. But for a swept wing or one with a root and tip that are different sizes its the best option to use.
It gets a bit techie but the simplest definition I found is this.
G93 stands for Inverse Time Feed Mode. The F code value, when DIVIDED INTO 60, is the number of seconds that the motion should take to complete.
Can be used on Mill, Lathes and Plasma cutter as well.
|Needs extra hardware for USB.|
Not being developed anymore.
General-purpose and still being developed
Parallel Port or Mesa Card
|DevCNC Foam||€60||Yes||Yes||Designed for 4 axis foam cutting|
Support several controllers
Very easy to install
|Can only be used for foam cutting|
|4 Axis GRBL||$0||No||No||Cheapest USB option||Arduino Mega and Ramps broad only.|
May need extra testing to get a good feed rate.
Hopefully, this post will help you decide the best option for you. I’ve just started using DevCNC Foam and will follow up later with a more in-depth article. When we decide to build a CNC foam cutter we tend to concentrate on the hardware but over the years of foam cutting, I’ve found this may not be the best option
Software is where you’ll spend the bulk of your time. So I would suggest you think about the type of projects you want to make and then match that to the software and then the hardware.
CNC foam cutting doesn’t not as precise as a CNC routing/milling machine so you don’t need to spend a fortune of super-accurate hardware. I have printed out profiles of wings and fuselages sections and then overlaid them on the foam cut part and to the naked eye, they line up perfectly.
If you have any questions then feel free to contact me and I do my best to answer them.
Happy foam cutting