A Beginners Guide to using a CNC Machine
A CNC machine is an excellent tool to have in your home workshop? Once you have shopped around and bought the right model to suit your needs, you will be able to cut out beautiful designs quickly and accurately.
However, the research doesn’t stop at the purchasing stage. There is a lot to learn once you first install a CNC router.
Various types of skills are required, from setting up and installing software, to running the machine and using design programs. It is a lot of fun, but it can be a steep learning curve.
Thankfully the internet is full of valuable information on how to get to grips with CNC modelling and engraving.
In this article we have pulled together some handy details, videos and guides to work as a stepping stone for you to increase your knowledge (and therefore confidence) when it comes to using your new machine.
Knowing what type of CNC machine to buy
We won’t cover this in great detail here, because many of you will have passed the buying stage in your journey.
The fact is however, there are many types of CNC machine available.
We have covered some of the best home workshop CNC routers here. Beyond those in a list you can also find 3D Printers, CNC Plasma Tables and larger scale CNC Milling Machines.
The important thing is to fully ascertain exactly what you want out of the machine. By knowing your own requirements, you can begin to look at the type of model that will fit the bill.
The video above gives an overview of the various types of CNC machines. Other resources on choosing a CNC machine can be found here.
How to use a CNC Machine
They say a picture is worth a thousand words, so imagine how many words a video can make up for. That’s why using Youtube is so great when it comes to tuition and trying to learn new skills.
There is an abudance of materials on site with details on how to use a CNC router. In our opinion, the best you will find is the one embedded below.
The author goes in depth covering set up and installation, as well as the ins and outs of creating your first model. An absolute gem for beginners.
Learning the software
Learning the software is a big part of CNC machining. It is also the area that can put people off, especially those used to working with standard woodworking tools that are less cryptic and a whole lot more tangible.
CAD drawing software may be your first port of call. This is where you can begin creating your designs.
G-code is then the most common way that computers will talk to your CNC machine, taking the designs created with the CAM software and turning them into 3D objects.
It is a very satisfying process to say the least.
And while you can start out doing basic manual-style machining on your CNC, the real development comes after you have connected up your computer and start using the software.
This of course takes time to learn.
Getting your head around the design studios (whichever you choose to use), and also learning a little g code will reap dividends over the long term.
Your work will be a lot more efficient if you are able to make simple changes to the g-code programs your CAM software generates. Faster, more accurate results are what we all strive for.
Again, youtube is one of the best ways to dip your feet into the software and programming side of CNC machining.
The best video we have found is the one embedded above. Click here and you will also find an excellent short online course taking you through how to use a CNC machine, g code and CAD.
5 Quick tips for better CNC machining
So you’ve bought the right machine, learnt a little on the programming and have got to grips with the actual nuts and bolts of using it.
Practising on demo projects is by far the best way forward. The more you experiment the more you will discover (on the machines capabilities as well as your own).
However, once you are up and running and are fully immersed in the practical side of CNC work, there are a few good pointers to follow.
And that’s exactly what we have set out in the simple steps listed below
1. Choosing the right cutters for text engraving
A popular use for a CNC machine is letter engraving. When creating small text you should use thin cutting tools for better results. The angle and nose should also be small. Only use the larger sized cutting ends on big text patterns. You should also use heavier graded cutting tools when working with harder materials.
2. Working with low power spindles
When working with low-power spindle motors you should opt for small shank tools (3.175 mm, 4.0 mm) so as not to exert too much strain. The cutting speed should also be reduced to compensate the level of friction occurring.
3. Blade length Choices
When choosing the blade length to use, you should add 2 or 3mm on the measured processing sheet thickness. For other applications such as acrylic (i.e hard materials) a long blade should not be used. Likewise, avoid using long blades with rpms over 200000.
4. Double-edged combination blade knives
When you get to the stage that you are using double-edged combinations blade knives (with a carved lens) you need to consider the blade diameter and length carefully. A helpful equation to remember is that blade length= plate thickness – bevel depth. Use this and you will be able to close in on the ideal size to go for.
5. Keep it maintained
You may reach a time when your tools seem to be breaking more than they should. Beyond the natural effects of ageing instruments, it could be that your carving settings are out. Check variables such as rail and motor configuration. Is everything tuned as it should be? Remember that your CNC machine needs to be serviced periodically. Fail to do this and components can and will start to malfunction.