Top 5 Bottlenecks in CNC Production

Image Credit: Greg Rosenke via Unsplash

In the highly competitive world of CNC production, efficiency and productivity are key factors that determine the success of a business. A crucial aspect of maintaining this efficiency is identifying and addressing the bottlenecks that can hinder the smooth operation of production lines. As CNC shops strive to keep their machines busy and maximize productivity, it is essential to understand and tackle the challenges that may stand in the way.

In this article, we will delve into a range of issues faced by CNC shops, from machine downtime and programming setup time to tooling, material handling, logistics, and quality control. For each bottleneck, we will examine the underlying causes and present potential solutions that can help businesses overcome these obstacles and optimize their production process.

By exploring the intricacies of these bottlenecks and implementing the appropriate strategies, businesses can ensure their machines are working at their full potential, ultimately leading to a more successful and profitable operation.

Join us as we navigate the world of CNC bottlenecks and uncover the keys to unlocking maximum productivity and efficiency in the CNC machining industry.

1. Machine Downtime

Machine breakdowns, as well as maintenance requirements, are common causes of any significant downtime or disruption dealt to production schedules.

Downtime can vary widely across various types of CNC technology. For example, CNC metal stamping stands out as being a method that involves significant machine downtime, not least because of the disproportionate length of time it takes to get a press ready to run. Downtime occurs mainly due to the lack of an operator to perform required functions, and they simply cannot attain utilization as high as other technologies due to the time required for changeovers.

Technologies such as horizontal lathes show downtime for different reasons: they require more cleaning and mechanical servicing than other machine types. Tool wear and mechanical failure itself can also be significant causes of extensive machine downtime.

According to the 2019 State of the Industry report for CNC machining, by far the most quoted reason for downtime was an unavailable operator. The cause of this is related to a wider cause that everybody in the industry is aware of: the inability of businesses to find enough skilled labor to run their shops.

One possible solution to this paradigm is to make a strive toward automation. Trends show that automation is increasingly the solution that manufacturers are turning toward in order to make up for a skills shortage.  So-called “lights-out” manufacturing is the goal of production lines aiming to reduce the reliance on human availability, by supplementing it – or even replacing it – with the robustness of machine autonomy.

2. Programming and Setup Time

Setup time is undoubtedly one of the most important stages of any CNC shop’s entire process. Often, it is setup time that a shop’s technicians may spend the majority of their working time on, particularly in high-mix, low-volume environments. Each job may have vastly different requirements, requiring a highly specialized setup process.

A robust setup process is not something where corners can be easily cut: performing setup erroneously or to insufficiently high quality assurance standards may lead to very high scrap rates, lower yields, or poor product quality, in turn resulting in lost/delayed orders and lower customer satisfaction.

That said, the optimization of setup times and minimizing machine idling yields significant benefits in terms of return on investment (ROI), labor utilization, and overall product quality.

The process of reducing CNC machine setup time is an individualized process that depends on the exact setup of your shop. What the process invariably involves is data sourcing and documentation. The current state of the machines should be measured and logged, and the runtime of each stage of the process detailed.

From then on, certain stages that have the potential for optimization can be identified, and a baseline set. Then begins the work of establishing methods to reduce time spent: internally, this might include a system of organization of tools and cleaning supplies. In terms of optimizing technicians’ time, a system of digital instructions relayed to the worker in series may be instrumental in rapidly diagnosing and fixing issues.

In terms of how this recording, diagnosing, and implementation is done, your business could see benefit from a comprehensive MES, such as AMFG. Machine integration yields analytics that can help identify frequent blockers and their causes, helping vastly with the recording and diagnostics stage. Digital instructions or even digital workers can be employed at each stage of CNC production in order to lubricate the workflow and keep timely and costly blockers from ruining a day’s output.

3. Tooling and Tool Changes

Another bottleneck comes in the form of how your business handles tooling.

First of all, tool selection is a critical component that may cause bottlenecks in your production line. The incorrect tool for the job will result in a poor quality finish for the product, as well as faster tool degradation, meaning higher costs for the business. These issues arise in tool programming too: running the incorrect settings for the tools once they are changed in the machine can result in avoidable wastage.

Insufficient tool inventory is another reason why unexpected bottlenecks can appear per each job. Keeping track of tool health is of the utmost importance, since when a tool that has been relied upon is now no longer usable, the entire next phase of the process cannot begin until the tool has been reordered, delivered, and made available.

One crucial step in tool management is making all tool data available and transparent at the earliest opportunity, to help your business make smarter decisions about the availability of tooling. AMFG’s MES offers features including real-time tracking of tools, automated dispensing and retrieval of tools, and monitoring tool performance. These capabilities contribute to the reduction of setup and changeover durations, optimization of tool utilization, and prevention of errors or accidents arising from the use of faulty or unsuitable tools. Furthermore, AMFG’s MES plays a significant role in gathering and analyzing data by offering extensive information related to tools, such as inventory quantities, tool usage patterns, tool conditions, and overall tool performance.

See our Guide to Managing Your CNC Inventory for more tips and solutions when it comes to optimizing the tool inventory of your machine shop.

4. Material Handling and Logistics

Next, the logistics of material sourcing, storage, and shipment can cause untimely delays that disrupt production schedules.

One oft-cited problem with material imports is issues in the supply chain. These problems are exacerbated by shortages in critical components, causing inflated prices, and labor shortages, also leading to higher costs and shutdowns. This impacts the reliability of manufacturers, who repeatedly fail to meet customers’ demands.

So, what is the solution when it comes to bottlenecks in logistics?

Advanced inventory management systems, such as that contained within AMFG’s award-winning MES package, can monitor the market and use smart parameter-setting to ensure that orders of raw materials are placed right when they are cheapest, in order to buy in bulk for storage. CNC workflows that involve mass production of parts of similar specification will benefit most from this.

In terms of smaller, per-job material requirements, a digital warehouse functionality can help drive on-demand manufacturing and ensure that predicted production timelines are met. This becomes a particularly useful feature when repeat parts are requested, since all material parameters are documented and can be easily referred to when a part is made again.

5. Quality Control and Inspection

The final bottleneck to discuss comes toward the end of the CNC production process: quality control. Assuring the quality of the output is the make-or-break stage of the production process, as if a part fails, the whole process is likely to have to be repeated again, potentially risking further unforeseen bottlenecks due to the job being repeated one more unexpected time.

Further, if a highly-specified process needs to be repeated for a second pass, parameters set by individuals in the previous pass may not be adequately documented, a communication problem that can lead to delays before adequate information is obtained.

In turn, these “bottlenecks” may not simply slow production down, but lead to a complete rework and thus higher scrappage rates.

Immediate solutions can be sought in establishing more frequent and more stringent inspections. This is because time spent before a problem arises pays dividends when a job finishes, passes inspection, and does not require rescheduling. Sourcing the right materials for the job, and even the right machine for the job, are other important areas to review.

A software solution that provides businesses with a more rigorous quality control system can also be found in an MES such as AMFG. In order to gain visibility over the entire process, a system of comprehensive log-keeping must be employed, particularly for when low-volume parts are reproduced. AMFG’s complete traceability feature ensures that every step in the process is logged and documented, complete with timestamps and the authors of such changes. In turn, this helps vendors to comply with ISO 9001 and other certifications, increasing their legitimacy for customers.

Mitigate Your Bottlenecks with an MES

As we look toward the future, the potential for MES software in addressing the various bottlenecks in CNC machining is immense. By harnessing the power of automation, advanced inventory management, and comprehensive quality control, MES solutions can revolutionize the way CNC shops operate, ultimately leading to a more efficient and cost-effective production process.

One exciting prospect is the continued development of “lights-out” manufacturing, which has the potential to significantly reduce downtime caused by the lack of available skilled labor. As automation technology advances, the need for human intervention in the production process will decrease, paving the way for more streamlined and reliable production lines. This shift will not only help businesses overcome the challenges of finding skilled labor, but also increase the overall efficiency and productivity of CNC operations.

Moreover, the integration of MES software into the CNC machining process can help optimize programming and setup times, making it easier for technicians to diagnose and fix issues rapidly. By providing real-time data and analytics, MES software can pinpoint areas that need improvement and facilitate a smoother, more efficient workflow.

The implementation of lean manufacturing principles and digital warehouse functionality through MES software can improve tooling and logistics management, ensuring that businesses can better manage their inventory and reduce wastage. This will ultimately lead to a more cost-effective and efficient production process, enabling CNC shops to remain competitive in the industry.

The adoption of MES software has the potential to greatly impact the future of CNC machining by tackling the most pressing bottlenecks in the production process. By embracing automation and advanced software solutions, businesses can optimize their operations, improve efficiency, and stay ahead in the rapidly evolving CNC landscape. With the ongoing advancements in technology, the potential for MES software to revolutionize the CNC industry is boundless, paving the way for a more innovative and productive future.