CNC (or computer numerical control) machining is a subtractive manufacturing process in which pre-programmed software and code dictates the movements of factory tools and machinery. It delivers high speed, high precision, and robust manufacturing solutions. You take a block or billet of material and cut away at it with a series of tools and drill bits, removing material to make CNC machined parts.

CNC prototyping uses computer-controlled machines to make precise prototypes from digital designs. These machines carve out shapes from materials like plastic, metal, or wood based on the design. Starting with a digital model, the CNC machine follows exact instructions to create the prototype, ensuring high accuracy and intricate details.

Unlike traditional prototyping methods, CNC rapid prototyping allows for iterations within days. This process speeds up product development by allowing quick testing and adjustments before making the final product. Industries like automotive, aerospace, medical and electronics use CNC prototyping to test concepts, refine designs, and ensure quality before mass production. It’s a vital step that brings ideas to life, improving products and meeting high standards.

CNC parts could cost from as low as a few dollars, or as high as $1000 or more. The price depends on the material, tolerance, machining hours, geometrical complexity, part size or quantity. Learn how suppliers calculate the cost of your CNC part.

The two primary CNC machining processes are CNC turning and CNC milling.

CNC milling shapes out of a metal or plastic material blank that is usually flat, holding dimensions to tolerances as tight as 0.002”.
CNC turning rotates the part when machining the desired shape, which results in cylindrical parts.

We use a third CNC machining process known as EDM or electrical discharge machining.

EDM also known as spark machining, uses thermal energy instead of mechanical force to remove material from a workpiece. It is often used to produce sharp internal corners or particularly deep cavity.

Many industries rely on CNC machining for high-precision parts and prototypes, including:

• Aerospace & defense
• Automotive
• Electronics
• Robotics
• Medical
• Oil & gas

For features left unspecified, standard tolerances are used. The standard machining tolerance is ISO 2768 Fine (F) for metals and Medium (M) for plastics. Tighter tolerances are available on request.

Generally, we would recommend CNC machining parts over 3D printing, as CNC machined parts are functionally stronger than those 3D printed and typically have superior production quality. This is why CNC machining is typically used in the mid to late stages of development, when parts are ready to be tested for functional accuracy.