The world of CNC milling machines is as vast as it is varied.
Between the different uses of the machine (craft, design, prototyping, DIY), the rich ecosystem of CNC software available (CAM, CAD, etc.), the wide variety of materials that can be worked and the countless players offering CNC milling machines, it's easy to make a mistake when choosing a CNC milling machine when you're just starting out without asking yourself the right questions.
But don't panic: a little thought and common sense will help even the most inexperienced choose a CNC machine after reading this article.
In this article
1) Choosing your CNC milling machine according to its purpose
1. What types of material do you want to mill?
2. What types of material do you want to mill?
3. What volume of production are you planning?
4. Choosing a CNC milling machine to suit your space requirements
5. How many axes does your CNC milling machine need?
2) Choose a CNC milling machine suited to your skills
3) How do I choose a good quality CNC milling machine?
1. Warranty and after-sales service
2. Online reviews
3. Technical specifications to check
4. Compatibility and repairability
4) Choosing a CNC milling machine based on your budget
5) Other criterias to choose your best CNC machine
1. Opt for a scalable CNC machine
2. Compare different CNC machines
3. Opt for a CNC milling machine kit (or not)
4. Look for alternative financing options
1) Choosing your CNC milling machine according to its purpose
What do you intend to do?
This is THE crucial point to consider when you decide to buy a CNC machine. Your intended use will largely determine your ideal CNC milling machine model.
1. What types of material do you want to mill?
Wood, metal, MDF or Plexiglas: a CNC machine is a highly versatile tool that can work with a wide variety of materials. Before you buy, think about the possibilities you want to have in the future.
By opting for an entry-level CNC milling machine, you're saving money, but you're also depriving yourself of a number of options for your future projects. Most of the less expensive CNC models are unable to machine more solid materials efficiently.
It may be possible to machine a metal project with a small 3018 CNC, but this will mean very limited milling speed and low precision due to the high resistance.
And don't forget that the choice of an appropriate, quality milling end-mill will also have a considerable impact on the result obtained.
To get a better idea of what can be done with different CNC models, you can refer to our materials library and the tips it contains.
2. What degree of precision do you need for your projects?
Do you need a CNC machine to make jewellery? Carpentry? Prototyping or ice sculpture?
All these uses require very different degrees of precision, depending on the quality of your future acquisition.
Generally speaking, each machine has an estimated cutting accuracy, which should give you a good idea of what you can achieve with it.
This degree of precision depends largely on :
- The rigidity of your machine, which may be influenced by the quality of its design, fixings and assembly.
- The spindle and its method of movement and rotation.
- All the technical characteristics of the CNC machine (see part 3)
- The skill of the user and the milling parameters he or she selects.
Please note that when this value is mentioned, it is generally indicative and often embellished by the manufacturers.
To be on the safe side, it is therefore advisable to cross-check the information provided by the dealer with user feedback to ensure that the machine really does live up to its promises.
3. What volume of production are you planning?
Generally speaking, acquiring a CNC milling machine is a fantastic way of boosting your production. However, some models are better suited to intensive use than others.
In this case, the spindle speed is closely linked to the performance you can expect from your CNC milling machine for fast production.
A sufficiently powerful spindle will not only enable you to carry out operations more quickly, but also for longer. A spindle with less power, on the other hand, will force you to slow down or even stop your machining session if it overheats.
As well as the power of the spindle, the torque of the machine's motors also plays an important role in maintaining the performance of a CNC milling machine. A motor with higher torque is essential for harder materials or deeper cuts.
To define the ideal cutting parameters once you have your machine, you can rely on our guide to cutting and feed speeds.
4. Choosing a CNC milling machine to suit your space requirements
Do you prefer to work in your workshop or from your office?
The answer to this question will certainly have an impact on the amount of space you are prepared to devote to your future CNC machine.
Think carefully about the type of workpieces you plan to machine, their size, the work surface you need and the storage of materials to be used before opting for one CNC model or another.
Another point not to be overlooked is the delivery of your new piece of equipment: while some CNC machines are delivered in kit form, others will be offered to you directly assembled, which could complicate the passage through smaller spaces (doors, stairwells, etc.). Find out all you can before making your choice.
Note: If you hear talk of 3018 or 4040 CNC machines, be aware that these numbers simply refer to the available work surface.
5. How many axes does your CNC milling machine need?
If you're looking for a CNC milling machine to start with, there's a good chance you'll opt for a 3-axis CNC machine (length, width and height), but it's also possible to work with 4-axis CNC machines (length, width, height and rotation around a single axis), or even 5-axis machines (length, width, height and rotation around two axes).
The latter two options, however, involve much higher levels of complexity, as well as significant costs, particularly for the use of the CAD/CAM software required for 3D modelling of this type of object.
For this reason, unless you already have a very specific project in mind and a solid knowledge of machining and 3D modelling, beginners are best advised to start working with a 3-axis CNC machine.
2) Choose a CNC milling machine suited to your skills
If you start playing guitar without any previous knowledge of an instrument, starting to learn it with a Metallica guitar solo is the best way to get discouraged before you've achieved anything. In the same way, choose a machine that's suited to your level of maturity in the small ecosystem of CNC milling machines.
If you're not yet familiar with terms like CAM, CAD, CAM, CAD, G-code or post-processor, it's probably worth checking that there are relevant help resources for the machine you're planning to buy.
The existence of a good after-sales service, appropriate tutorials or online training offers are all positive signs if you're planning to embark on this brand new adventure. There's nothing more frustrating than seeing a machine gathering dust after you've put your maker skills to the test, so save yourself the disappointment.
3) How to choose a good quality CNC milling machine?
Judging the quality of a CNC machine is far from easy, as the gap between perceived quality and actual quality can be considerable.
Many CNC milling machine manufacturers pride themselves on offering solutions that are easy to use, accurate and inexpensive, but miracles are rare.
If you want to avoid false promises and be sure of the quality of your future purchase, there are a few things that can tell you a lot.
1. Warranty and after-sales service
If there's one indicator that should inspire confidence when buying a digital milling machine, it's the longevity of the warranty associated with it.
The longer the warranty, the more confident the manufacturer is about the quality of the machine it offers, and the more reassured you can be about the support you'll be able to get if anything goes wrong.
A warranty period of one or even two years is the usual minimum standard for most CNC milling machines, but some manufacturers (such as Mekanika) go as far as 5 years for maximum confidence.
2. Online reviews
A warranty is nothing if your calls for help go unanswered.
That's why it's always worth doing a little research into the online reputation of the brand whose CNC milling machine you're considering.
Even if they are sometimes to be taken with a pinch of salt, taken as a whole, user feedback generally gives a reliable picture of what you can expect from a manufacturer and the quality of its after-sales service.
3. Technical specifications to check
What equipment is included with the CNC milling machine?
This first technical point is crucial: at first sight, some tempting offers mask shortcomings that can quickly prove costly as they accumulate.
Among the questions to ask yourself are the following:
- Do you get just the mechanical parts, or is everything included?
- Is CNC control software included?
- Is the spindle sold separately?
- Which accessories are included and which do you really need (martyr, Z probe, etc.)?
- Is an additional external computer required to operate the machine?
- Is a laser included with the machine or available as an option?
- Will you need a vacuum table with your machine in the future ?
The general design of the machine
This is usually the first visual indication of quality.
To operate accurately and optimally, a CNC milling machine needs good stability and robust materials .However, you need to be wary of the excesses that some manufacturers fall into by offering unnecessarily massive tools at inflated prices.
That's why it's vital to base your considerations on other, more objective criteria.
Spindle power and concentricity
The spindle is the central part of any CNC milling machine and will determine the quality of the results you obtain. Comparing the power and concentricity of the spindles of the machines you are interested in is a good way of judging the performance you can expect from a machine.
In concrete terms, the power and quality of the spindle supplied will determine the cutting and feed speeds as well as the size of the swarf produced, and therefore the intensity of use to which your CNC machine can be subjected.
The CNC milling machine drive system
Every CNC machine has a drive system that will influence its precision.
Without going into the technical details, the most advanced CNC models generally use prismatic rails with ball-and-socket joints, while more basic models make do with a belt-and-pulley system that is slightly less precise, but cheaper.
Z' retraction
On a CNC milling machine, Z-axis clearance should not be overlooked, as it will determine the height of the workpieces your machine will be able to machine.
Limit sensors
Having a complete sensor system may seem like an accessory, but it is nevertheless a good way of saving time, improving precision and increasing safety.
A series of mechanical sensors is a first step, but inductive sensors will enable you to mill in optimum conditions if you can afford them.
4. Compatibility and repairability
Make sure you choose a CNC milling machine that is compatible with your favourite CNC software!
Some brands only work with proprietary software, sometimes with subscription fees.
If you already have your preferred modelling and machining software, or if you want to retain complete freedom of choice, opt for a more open, or even 100% open source, brand.
The same applies to the hardware aspect of the machine: CNCs are complex machines with many moving parts, and it's important to have access to spare parts.
4) Choosing a CNC milling machine based on your budget
This is obviously a decisive point when choosing a CNC milling machine to start with.
From a few hundred euros to several hundred thousand, there is a very wide range of CNC machines to suit your budget and your requirements.
The choice is not easy, but if you have already established your requirements in relation to the various criteria we have just mentioned, it should already be much more limited: by now you should know what are the main elements you definitely need to achieve your project !
5) Other criterias to choose your best CNC machine
To make it even easier for you to make a final decision, there are still a number of options available.
1. Opt for a scalable CNC machine
Some machines offer the possibility of evolving with your use of them.
Choosing a CNC milling machine to start with, in the knowledge that it will be possible to upgrade it if your work becomes more professional or intensive, is a good way of making a choice without giving up.
For example, the EVO CNC machine is a good option for getting started with digital milling, and can be converted to a CNC PRO machine with an upgrade kit if your activity becomes more demanding.
2. Compare different CNC machines
There are many guides and comparison tools available online to help guide and facilitate your decision making. Unfortunately, given the multitude of CNC machines available on the market, these are never 100% exhaustive and can sometimes be very biased.
3. Opt for a CNC machine kit (or not)
Although it may seem frightening, there are several considerable advantages to assembling your own machine:
- Full control and understanding of your CNC machine: By assembling your machine yourself, you become familiar with its configuration and gain greater autonomy and skills.
- Limited external costs: The option imitates both the assembly and shipping costs associated with the CNC milling machine.
- The guarantee of being able to easily transport the CNC machine to its final installation location, even for workshops that are more difficult to access
4. Look for alternative financing options
Sometimes companies and resellers offer creative financing options like CNC machine leasing or gradual payments programs for people on a tight budget.
This can be a good way to start with CNC machining without having to front the entirety of the costs.
6) Ask for advice
What better way to get started in the world of CNC machines than to call on the age-old wisdom of the wise makers who came before you?
There are many dedicated groups and forums available online, but you can also call on experts to guide you towards the best choice of CNC milling machine for you.
Don't hesitate to contact our team, who will be delighted to help you in your search.