CNC machining is a manufacturing process that starts with a solid block of some material from which parts are removed to get to the final shape. The process requires using cutters and rotating tools controlled by special software.
Then there is 3D printing, a process that creates parts by adding layers of melted material on top of each other. Unlike CNC machining, 3D printing doesn’t use special fixtures or tools. That alone significantly reduces the initial setup cost.
Here we will present the primary technology considerations that can help you choose the most suitable technology for your project. Here’s what we got.
Selection of Materials
CNC machines can use a wide selection of materials such as thermoplastics, machining wax, modeling foams, hardwoods, softwoods, metal alloys, acrylic, etc. However, different materials require the use of various cutting tools. Replacing tools is pretty easy and fast.
On the other hand, most 3D printers are restricted to thermoplastics such as ABS, nylon, PLA, etc. Recent advancements in 3D printing allow you to work with other materials such as wood and metal.
In this regard, CNC machines win the day!
It’s not easy to compare speed as 3D printers and CNC mills are mainly used for making different products with different features and materials. But, hypothetically speaking, if they went to create one same product, it is expected for the 3D printer to be somewhat slower.
A 3D printer might need three or four hours to create a particular product, while a CNC milling machine will most likely need an hour or so for the same.
So yes, CNC milling is faster than 3D printing.
Vibrations & Noise
A CNC machine working on a metal or a wooden block can be quite noisy and sometimes creates heavy vibrations. On the other hand, if the CNC machine is working on a wax model, there won’t be any considerable noise.
Concerning vibrations and noise, 3D printers are far superior as there is almost zero vibration. Also, the noise levels are rarely an issue, at least not as with CNC milling. Certain types of 3D printers, as well as some with an enclosure, are entirely silent during the printing process.
The conclusion in this area can be only one – 3D printers are quieter and don’t vibrate.
Specific professional CNC mills can offer accuracy up to 0.003mm, while most mills average just 0.020 mm. Some high-end 3D printers can reach an accuracy of 0.20 mm, but that’s the best from their world.
Strictly looking at which technology is more accurate, CNC mills are obvious winners.
Waste & Messiness
In CNC milling, a lot of material is removed from the block, which creates a lot of waste, and the mess can be quite big. On the other hand, 3D printing creates no or little waste, and on rare occasions, when there is something wrong with the filament or the 3D printer, there is some mess that needs to be cleaned. But in most cases, there isn’t any mess at all.
The obvious winner in this category is 3D printing.
Each technology has its advantages and drawbacks. Which one is better suited for your project depends on many factors. Hopefully, our comparison can help you choose the right technology for your project.