What Is Secondary Machining?

Key Takeaways

• Secondary machining customizes existing parts by modifying standard or previously machined components, avoiding the need to manufacture new parts from scratch.

• Reduces cost, lead time, and material waste for design changes and custom modifications.

• Best suited for simple modifications like adding holes, keyways, grooves, or dimensional adjustments.

Overview

Secondary machining refers to modifications made to components that have already undergone machining or molding processes. The most common case is modifying standard manufacturer parts to meet specific requirements, effectively creating custom components.

Standard parts from manufacturers are convenient because specifications are available in catalogs, and they can be procured quickly. However, slight adjustments are sometimes necessary, such as correcting dimensions or adding extra holes. Secondary machining provides a fast, cost-effective solution in these situations.

Benefits of Secondary Machining

Secondary machining allows for re-processing of existing parts, providing several key advantages:

• Lower Cost: Modifying an existing part is often cheaper than producing a new one. It reduces both material and machining costs.

• Faster Turnaround: Partial modifications can be completed quickly compared to manufacturing a new component.

• Reduced Waste: Reusing parts through secondary machining minimizes scrap and material waste.

• Flexibility: It enables quick adjustments to accommodate design revisions or new functional requirements.

Typical applications include customizing machine parts such as enclosures, flat bars, aluminum frames, couplings, boxes, and cases. Common operations include cutting grooves, drilling angled holes, or punching shapes. Most of these modifications are done using machining processes like milling and turning.

When only partial shape changes are required, it helps reduce both material and machining costs, enabling low-cost and quick delivery. However, for shapes or materials that are difficult to machine, the cost can actually be higher. In such cases, secondary machining might not be as effective as new production.

Examples of How Secondary Machining Are Used

• Adding holes to boxes or cases

• Adjusting the diameter of gears

• Adding keyways

• Post-processing adjustments after design revisions

• Developing custom components from standard parts

For example, a plastic case from a manufacturer may be modified with additional holes. While some manufacturers handle these adjustments, requests may also be outsourced to third-party machining companies based on lot size or delivery schedules.

Secondary machining is also used for in-house custom parts. For instance, a gear may be reshaped to fit a redesigned shaft, avoiding the time and cost of creating a completely new part. This process helps reduce project delays, minimize waste, and optimize development schedules.

CNC Machining at Yumoto Electric

Yumoto Electric delivers high-quality components fast, worldwide. We provide precision machining for a wide range of metals using milling, turning, and specialized metal processing. We have experience with over 200 materials including aluminum alloys, stainless steel, molybdenum, and titanium. 

If you’re unsure about material selection or machining methods, we offer complimentary consultations to help optimize your design and production. For any questions, please feel free to contact us.