Aerospace plastic machining

Product designers are looking for ways to counter the rising price of metals and replace machined metal parts with plastic components, and machine shops are finding plastics machining profitable.

The decision to get into machining plastics should not be taken lightly, because most of the plastics are sensitive to changes in temperature and humidity. The material is often inconsistent.

Quoting on a plastic machining job is often more difficult than quoting on a metal machining job. A very soft plastic may have to be frozen in order to machine cleanly. While most plastic components can be easily machined with high-speed steel tools, fiber reinforced plastics usually are machined with carbide or hardened steel tools because of the higher wear factor. In all cases, the tools need to be very sharp.

Experienced operators liken plastics machining to machining aluminum, where a sharp tool is much more important than a hard-edged tool. At higher cutting speeds some plastics will melt because of the higher heat. Machine too slow and the drill sits there too long and builds up too much heat. There are however some plastics that can withstand high temperatures.

When it comes to aerospace, plastics machining is preferred over some materials because of its heat-resistance. Plastic materials and plastic machine parts are used in solid fuel booster and ablative shields to allow re-entry of space shuttles.

Plastic components for helicopters

In manufacturing helicopters, plastic materials and plastic precision machining play a key role for durability, flexibility and capacity to absorb vibrations. Its strength means the weight of the aircraft can be reduced without compromising quality and safety.

Plastic was first introduced as a substitute for rubber machining in items such as fuel-tank linings. Today, plastic engineering continues to evolve with technology. For pipe systems, plastic precision machining and plastic materials require less maintenance.

Lightweight, with high-impact resistance, corrosion resistance, easy processing, high-wear resistance, plastic materials increase productivity, improve appearance and require less lubrication. Polyethylene machined parts are also recyclable and environment-friendly.