Design Principles for Optimizing Plastic Parts in CNC Processing

With the rapid development of 3D printing and CNC technology, more and more plastic parts are produced using CNC processing. Correctly designing parts is critical to production efficiency and product quality. This article will share several design principles and explain each principle in detail to guide the design of plastic parts.


## Consider the ease of processing

The difficulty of CNC processing mainly depends on the appearance and shape of the part. Simple planes and arc surfaces are relatively easy to process, but surfaces that require multiple rotations or complex structures are more difficult. The latter should be avoided to reduce costs. For example, a part that requires multiple rotations and positioning is difficult and costly to produce. Parts that can be processed with only one positioning will significantly reduce production difficulty.

## Pay attention to critical dimensional tolerances

Plastics will deform due to temperature. Tolerances that are too tight can lead to quality issues. At the same time, molds inevitably have errors. Therefore, the critical dimensions should be designed with 6-10 tolerance units to accommodate deformation and errors, and be easy to pass inspection to ensure quality.


## Avoid parts that are too small

Compared with larger parts, smaller parts have difficulties in CNC positioning and fixing, and the quality is difficult to control. Parts that are too small should be avoided. For example, multiple small parts can be integrally molded, or replaced with relatively larger sizes.


## Leave appropriate processing allowance

Reserve a machining allowance of 1-3 mm depending on the type of tool to prevent positioning errors from causing the surface to be incompletely processed or difficult to remove debris, which is beneficial to ensuring quality and smooth subsequent processing.


## Simplify the structure

An overly complex structure is not only difficult to process, but also difficult to ensure accurate positioning, thus affecting quality. Consideration should be given to simplifying the overall structure, such as breaking down a complex part into several relatively simple sub-parts and then assembling it.


In short, product design through the above design principles combined with the characteristics of CNC machining technology can significantly reduce production costs and also help improve product quality. This provides an important reference for the application of plastic parts in CNC services. By following these principles, designers can ensure that plastic parts are easy to machine, dimensionally accurate, and of reliable quality.

Post time: Jan-02-2024