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Hello! Today we will talk about money and machines. How do you choose a machine without making a mistake? What makes price a quality and brand indicator in all industries? Of course, there are exceptions, but this is often the case, especially when it comes to technology. So, let’s figure it out.
What matters
Machines may appear similar to someone who is unfamiliar with them. For example, the tube, ignition block, and other components might seem to be identical, but the crucial distinctions are in the design details, which are what actually matters!
Some laser equipment lacks gear reducers (gear boxes) that split the step, which is very handy for engraving! Or there may be a specific side opening and protective cover for adding a more powerful laser tube, as well as a through or lifting table with a chain mechanism for installing a rotational device.
In summary, the disparities exist, and they are in the nuances that have a big influence on the overall outcome of the task. Let’s discuss some of them more closely.
Bed and frame
This is the machine’s base, and its quality should be your primary focus, as not every bed and frame can maintain their shape throughout their entire service life. This is related to their rigidity and thickness.
Sometimes machine beds are made from v-slot structural profiles. Such a bed will take on the shape of the surface it’s placed on. In other words, to work on it, you’ll need a perfectly flat surface and a similarly level sacrificial table.
If the bed is fully welded and undergoes heat treatment, its resistance to loads increases, and it lasts longer without deforming. For example, Wattsan machines’ beds undergo a multi-step high-temperature treatment process to relieve material stress.
A good frame should be made of metal or cast iron. However, those made of plastic or wood not only have a short lifespan but are also potentially dangerous as they are highly flammable. Some might point to lightweight aluminum. However, it is also a questionable material, as it doesn’t prevent vibrations, which can lead to defects during work and cause the machine to misalign over time.
We should also mention vibration-damping supports. Their presence ensures additional resistance to vibrations that may occur during active engraving. So, make sure the model you choose has them.
Gantry
It must be securely fixed to avoid any misalignment along the axes. If the gantry is fastened with any looseness or not firmly enough, it may become misaligned. For example, if the spindle, while generating a heavy load, starts milling material on the right side of the work area, it may shift, and the left side, which is not experiencing the same force, could move out of alignment and stay that way for a long time.
The material used for the gantry depends on the machine and its type. For instance, specially designed extruded aluminum is often used for metal cutters. However, for router machines, it’s better if the gantry is made from thick-walled steel, ranging from 4 to 8 mm depending on the material. This is necessary to allow the installation of multiple spindles and to handle heavy loads.
Kinematic system
The guides along which the gantry moves during operation can vary: roller guides, shafts, or rails with carriages. The first type is used with structural profiles and does not provide much rigidity. A gantry on such guides may occasionally wobble, which affects the quality of the finished product. This is acceptable if absolute precision is not required.
Shafts, whether polished or supported, are relatively easy to install, affordable, but not very durable. Polished shafts in particular can sag in the middle under heavy loads.
Rail or linear guides, on the other hand, are used when reliable gantry movement is needed, as they offer additional rigidity and evenly distribute the load. Wattsan machines are equipped with exactly these types of rail guides with carriages from HIWIN.
The next element is the motors. They can be either stepper motors or servo motors.
A servo motor or stepper motor should be selected based on the equipment’s intended use, cost, and technological viability. Stepper motors are appropriate for CNC machines that handle soft materials and for applications like CO2 machines and some router machines where extreme accuracy is not needed. Servo motors are required for high-precision operations with hard materials, such as metal-cutting machines. We discussed this in more detail in another article.
Air extraction
The way this part is constructed will affect not only the cleanliness of the working area but also your safety. For example, certain materials release harmful fumes during laser cutting. However, a good fume extraction system is essential even for metal cutters.
In router machines, a proper aspiration system is crucial for removing chips. This helps to process the material accurately, protects the tools and spindle, and keeps the guides clean by preventing chips from sticking to them.
Software
Pay attention to what control system the machine uses. Some manufacturers develop their own control systems. These may not always be user-friendly, as a company primarily focused on producing machines may not fully understand how to design an effective control system. However, there are exceptions.
The problem with such controllers usually lies elsewhere — finding training materials for these specific controllers can be challenging due to the limited number of users. In case of a malfunction, you may only be able to seek support from one source.
On the other hand, there are well-established and widely used controllers around the world. First, they guarantee quality. Second, it will be much easier to find instructional videos or get help if you encounter difficulties!
Maintenance
When choosing a machine, don’t focus only on its components. Service and support are also extremely important when purchasing equipment, especially something like a CNC machine.
When buying, keep in mind that a low price could be an indicator that support is either lacking or will not be of the highest quality. Of course, there are exceptions, but it’s better to be safe and choose a trusted supplier and check reviews.
Machines may periodically require maintenance, and during that time, consultation might be necessary.
Conclusion
When purchasing a machine, don’t just look at the presence of certain components but also at their quality and manufacturer. Ask for a test run of the equipment to ensure your choice, and don’t skimp too much. The price of the machine is often justified by the cost of its components, which affects its lifespan. Even for a new business, it’s better to buy a small machine from a trusted manufacturer rather than a cheap one from an unknown source.
