The machining of nylon by CNC allows for the creation of intricate and precise parts. But how accurate can you get in real life? The achievable tolerances for CNC machining nylon generally fall between ±0.002" and ±0.005" (0.05 mm and 0.127 mm), though they vary depending on several factors. This is the approximate thickness of a human hair.

The following is a summary of the variables that affect tolerance when CNC machining nylon:

l Type of nylon: Different types of nylon have different properties; glass-filled nylons, for example, are more rigid and therefore usually offer tighter tolerances.

l Feature size and complexity: Smaller features and complex geometries naturally present greater challenges for maintaining tight tolerances.

l CNC machine capabilities: The precision and capability of the CNC machine itself will be crucial. Entry-level models cannot achieve tighter tolerances than more advanced machines with more features.

l Tooling and setup: The type of cutting tools used and the general configuration of the machining process can also affect accuracy.

The various tolerance ranges are shown graphically here:

l Hair (0.002" to 0.003"): When it comes to small, basic features, this is the tightest tolerance that can be obtained when CNC-machining nylon.

l Grain of rice (0.005" to 0.010"): This is a more commonly used tolerance range for CNC-machined nylon parts that are suitable for various applications.

l Penny (0.010" to 0.020"): When precise precision is not as crucial, these more accommodating tolerances are typically used on larger or less significant features.

It's important to keep in mind that attaining the highest tolerance levels might not be cost-free. Tighter tolerances usually require more specialized tooling, slower machining speeds, and higher machine calibration requirements, which can raise costs and prolong production times.