CNC Machined PEEK and Acetal High-Performance Plastic Parts

PEEK stock is expensive, so we nest parts carefully and program near-net roughing to protect yield. Its rigidity allows tighter tolerances than most plastics, but it generates heat when cut, so we use carbide tools with sharp edges, moderate feeds and air blast cooling. Acetal machines easily and is used for most functional prototypes. Annealed stock is preferred for PEEK parts that need dimensional stability after machining.

PEEK holds its properties in continuous service up to about 250 °C, resists most chemicals and is used where metal-replacement plastics must survive sterilization or hot oil. Acetal offers excellent stiffness and low friction at a fraction of the cost but tops out near 100 °C. PTFE is the chemical-resistance benchmark but is soft. Plastic parts are usually supplied as-machined; bead blasting gives a uniform matte look if appearance matters.

Because plastics relax after machining, final dimensions are measured after parts have stabilized at room temperature. Critical features are 100% checked with pin gauges, micrometers and CMM on complex geometry. Material certificates for PEEK and POM are available on request. Typical applications include semiconductor fixtures, pump and valve seals, medical device prototypes, electrical insulators and food-handling components.