I built a CNC machine in my garage. I sent the below email to some people wanting to know about my build and then thought I’d post it here for future reference or for anyone googling similar. Probably the links to AliExpress below will break over time but here you go…
To create a shape for cutting on your new CNC machine first you draw this shape up in a computer program that creates G-Code. There are many of these about and some very specialised but I choose to use Autodesk’s Fusion 360 because it’s a very high end product that is free to use for non-commercial use. I watched loads and loads of YouTube videos on how to use it and then create the toolpaths in the ‘Manufacturing’ module that you then export G-Code from.
Once you have some valid G-Code you need to open it up in an interface to send it to your CNC controller. Again there are loads of programs to do this and loads of users swear by purchasing something like Mach3 (or Mach 4) but I was choosing to go as cheap as possible and am using OpenBuilds CONTROL Software which does the trick.
Initially I was getting weird errors when running my G-Code and found that there was a much better G-Code post-processor which can you install in Fusion 360 to send more compatible G-Code for the ‘GRBL’ Controller I use. More info and download here – https://github.com/Strooom/GRBL-Post-Processor
OpenBuilds CONTROL Software communicates with your CNC Controller – it was here that I deviated from a standard OpenBuilds CNC kit as I already had an Arduino UNO lying about, but they are super cheap anyway
I also got a prototyping screw board to sit on top of it to allow easy access to screw connect wires to the Arduino.
The software (firmware) that gets installed on the Arduino is called GRBL – it takes the G-Code you send it and converts it into electrical signals for the motor controllers. You can find out all about it and download it from https://github.com/gnea/grbl/wiki
You flash it to your Arduino and you are good to have a play – having only spent about $8 at this point.
Once you are ready to commit to the machine you need to spend some real money.
The machine I have created is based upon an OpenBuilds WorkBee, of which you can find full details of here – https://openbuilds.com/builds/openbuilds-workbee-1510.7189/. Even within this machine design there are many options along the way including size, how it’s driven (belt or screw), and things like the controller, motor drivers etc.
Mine is a 750×100 Screw driven unit from these guys https://www.aliexpress.com/store/3881013 who I found to be very good. It included the instructions from these guys in the UK who sell a whole kit but it’s friggin expensive to consider getting it to NZ from them. The assembly manual can be found here https://ooznest.co.uk/wp-content/uploads/2019/02/WorkBee-Screw-Assembly-Manual-01-02-2019.pdf which will give you a really good idea of what’s involved.
A lot of my purchasing decisions were based around the cost of the freight as (for instance) purchasing the whole kit came to more than purchasing individual items with free freight and it gave me the flexibility to use my own controller and motor drivers for a much more powerful machine.
The Arduino UNO (CNC Controller) gets connected to the motor controllers of which you’ll need four – 1 for the Z axis, 1 for the X axis and 2 for the Y axis as you drive both sides.
For the motor controllers I elected to go with much higher power units than are generally used in the kit meaning that my motors will have much higher torque etc – I purchased 4 of these.
You need a power supply to supply voltage to the motors via the motor controllers and I got a 36V 10A one from here.
To connect things up I got a few other items such as…
- Shielded cable for connected up the motors etc.
- Fused and switched IEC power socket.
- Emergency Stop button – which came in super handy before I’d wired up limit switches.
- DuPont Connector plugs.
- Crimping Tool.
- USB Extension cable for making the connection to the Arduino.
To cut something like wood you’ll need a router and I purchased a Makita from Mitre10 – https://www.makita.co.nz/products/model/RT0700C
To mount your router or whatever you are going to use to cut with you’ll need a z-axis Router mount of the correct diameter for your router – my Makita is 65mm for instance – Obviously mounting the Plasma Cutter on there will be quite different but I’ve seen people do it with cable-ties etc. Google is your friend here.
To tidy up all the cabling I purchased a 2 Piece pack of these later on. It’s not necessary to run it but it does make things tidier
Also the build kit doesn’t come with limit switches so I ordered these – I didn’t use them initially but they make a significant difference so just do it.
I think that’s about it. Let me know if you have any questions.