Machined plastics solve problems metals cannot—light weight, electrical insulation, low friction, and chemical resistance. Each grade fits a different job.
ABS — the prototype favorite
Easy to machine, cheap, and good enough for most enclosures and jigs. Limited temperature and chemical resistance.
POM (Delrin) — the precision mover
Low friction and excellent dimensional stability make POM the go-to for gears, bushings, and rollers that must hold tolerance over time.
PEEK — the high-performance polymer
Withstands high temperature and aggressive chemicals and is biocompatible. Used in medical and semiconductor parts where metals are unsuitable.
Polycarbonate (PC) — the transparent one
optically clear and impact-resistant. Good for guards and lenses, though it machines with more care than ABS.
Machining notes
Plastics soften with heat—use sharp tools, modest speeds, and avoid melting at the edge. Clamp gently to prevent crushing thin sections.
FAQ
Which plastic holds the tightest tolerance? POM, thanks to low creep and moisture stability.
Can plastics be threaded? Yes, but use coarser threads and more engagement than in metal. More in the materials guide.