CNC fabrication is a very convenient and effective manufacturing technique that uses computer numerical control (CNC) technology to control the machines and tools that process a variety of materials and items.
Materials that can be machined on the machine for CNC precision parts machining
Almost any material that can be machined can be used on a CNC machine. It really depends on the application. Common materials include metals such as aluminum, brass, copper, steel and titanium, as well as wood, foam, fiberglass and plastics such as polypropylene, ABS, POM, PC, nylon and more. However, some materials are too soft or too soft and rigid to be machined on a CNC machine. For example, materials such as rubber or silicone are too soft for CNC machining, and ceramics are too hard for precision machining.
Common CNC precision parts machining uses
Using CNC technology and a variety of cutting tools, almost anything can be manufactured on CNC machines, from marine parts, mechanical parts to aerospace parts, which are often high precision parts, including shafts, gears, bushings, flywheels, cams, molds, propellers, etc.
The products that can be produced on a CNC machine depend on the type of machine used. Each type of CNC machine has its own machining capabilities for manufacturing the unique nature of the part. For example, a round or spherical part produced in a CNC turning center cannot be produced in a CNC milling machine. Parts produced from a milling machine cannot be produced on a CNC lathe, for example.
CNC precision parts that can be machined by turning products
In the CNC machining industry, CNC lathes are used to machine linear cylinders, oblique cylinders, arcs, and various threads, grooves, worm gears, and also some complex rotating surfaces, such as hyperbolic surfaces, etc. Typical CNC turned parts include shift knobs, knobs, pulleys, shafts, hubs, bushings, flywheels, etc.
CNC precision parts that can be machined by milling
CNC milling machines are mainly used to process various complex flat, curved and shell parts, for example, various cams, molds, connecting rods, blades, propellers, boxes, shell-shaped parts are processed by CNC milling. In summary, typical CNC milled parts can be divided into three categories: flat parts, surface parts and angle parts.
Each machine has its own accuracy level and machining sequence. Sometimes, some machining machines will be used to make certain parts.
So what can't CNC machining do?
Almost any part can be made on a CNC machine, but there are some limitations. Parts with certain features that are not suitable for CNC machining include
- Internal vertical angle
Since a CNC milling tool has a cylindrical shape, it will leave a radius on the inside vertical angle when cutting the inside wall. Although the tip radius can be reduced by using a smaller diameter tool, the internal vertical angle cannot be made no matter how small the diameter of the tool used.
- Precision parts with deep cavities
Due to the limited cutting length, tools usually work best when cutting depths up to 2-3 times their diameter in the die cavity. Milling cavities deeper than 4 times the tool diameter will greatly increase the difficulty of machining and tool breakage.
- Thin-walled precision parts
Thin walls are difficult to machine and are prone to deformation or fracture during CNC machining. Thin-wall machining requires multiple passes at low depths of cut, and thin features are also prone to vibration, making it challenging to machine them accurately and increasing machining time.
- Precision parts with cutouts
Some notches in the inner wall of a part are difficult to machine with CNC because the cutting tool cannot reach there for any machining.
Therefore, it is recommended to avoid using these features before designing CNC precision parts for machining.
CNC machining offers precise cutting and manipulation capabilities, and it is easy to say that almost any product made from wood, metal, aluminum, alloys and various other materials can be completely constructed or improved by using a CNC machine. CNC has its limitations, so it is recommended to avoid shortcuts before designing CNC machined precision parts.