3 Costly Mistakes to Avoid When Designing Your Next Machined Part

CNC machining has revolutionized modern day manufacturing and is employed by machine shops in most industries. Nearly every sector relies on CNC machining as a fabrication solution and depends on the high-quality parts created by CNC machines. CNC machining technologies have advanced significantly in recent years and are transforming the way manufacturers operate. But CNC machining requires the “right” part design in order to achieve maximum effectiveness. Poor designs can result in performance issues – including failure – that can be very costly to OEMs financially as well as to the brand’s reputation. Below are 3 costly mistakes to avoid when designing your next machined part.

It should be noted that not all machine shops can create quality CNC machined parts and heavy fabrications. These projects require specific tools, equipment, and processes as well as personnel with the right skills and expertise to handle such large structures. It is important that OEMs partner with a manufacturer, like ABS, that has the proven experience, facilities, and know-how to safely and successfully perform CNC machining and heavy fabrication projects. When you partner with us, we help you optimize your CAD inputs to avoid costly design mistakes and ensure a cost-effective manufacturing solution.

Unnecessary Features and Complexity

One of the easiest design mistakes is to overcomplicate the design which often results in longer lead times and manufacturing costs – and potential performance issues. CNC machines are very capable of producing complex designs but they are most efficient when creating simple shapes. Part complexity takes many forms and includes geometry, special features, surface finishes, and part size along with other specifications. OEMs should look for opportunities to simplify the design. They must also work with their CNC machining partner to look at design alternatives and ensure any complex features are “must-haves”. It is important that OEMs ensure that every aspect of the design is truly necessary to achieve the requisite functionality – and when in doubt, simplify and standardize to save costs during CNC machining, sub-assembly, and final product assembly.

Engraving is a specific example of a design feature that can drive up cost and reduce production efficiency. While CNC machines are capable of engraving, this step often requires a separate cutting tool resulting in more time to machine the part. Designers should consider if there are faster and more cost-effective methods for adding text to a part. If CNC machining must be used for engraving, designers should utilize simplified fonts and avoid really small text as well as embossed text. This may seem like a minimal design modification but embossed text requires the removal of millimeters of material all across the surface of the part which takes much longer than engraving which only involves milling the text itself.

Unwarranted Use of Tight Tolerances

During the design of complex heavy fabrications for CNC machining, it is imperative that OEMs define the “right” tolerances and work with a fabricator that has expertise in tolerance setting. The team at ABS assists customers with tolerance setting and is known for their ability to produce high-quality and complex products including impellers for turbo machinery OEMs world-wide. Machining a part to excessively tight tolerances drives up cost without providing value. A recommended best practice for heavy fabrication projects is to only apply tolerances when necessary and to utilize tight tolerances on critical areas of the part. Additionally, designers should consider that not all surfaces of a part require tolerancing. Following these measures avoids costly design mistakes and helps ensure project success, especially for highly intricate parts.

Designing Walls Too Thin or Cavities Too Deep

Designing walls for parts manufactured by CNC machining can be tricky and is often a source of problems. In fact, insufficient wall thickness is one of the most common causes of part performance issues or failure. There is a strong desire to minimize material usage, which leads designers to push the limits on wall thickness, often ending up with walls that are simply too thin and are susceptible to vibration that can lead to warping or failure. When designing wall thickness for CNC machining, material selection must be considered from the beginning of the design as not all materials require the same wall thickness. For example, the wall thickness that works for an aluminum part may not be suitable for a stainless-steel part.

Another costly design mistake to avoid is part cavities that are too deep. CNC machining tools have a limited and finite cutting length, which means these tools can only successfully mill to a given depth. As a general rule of thumb, CNC tooling is most effective when milling a cavity depth that is 2-3 times the diameter of the tool. Beyond this, special tooling may be necessary to achieve deep cavity milling – driving up the cost and time required to create the part.

Looking for an efficient and reliable CNC machining partner for your next project?

Contact the team at ABS to learn about our experience with heavy fabrications and our commitment to quality.

Why ABS Believes in the DFM Process

Design for Manufacturing (DFM) is the process of designing parts for ease of manufacturing as well as creating a better, more cost-effective product. A proper DFM process helps avoid costly design mistakes. DFM is especially crucial for heavy fabrications as these projects are typically large or oversized structures that are costly to remachine. Successful heavy fabrication projects must be designed from the beginning to be manufacturable.

At ABS, we believe DFM is a vital product-development step that looks to simplify and optimize the design to ensure high quality and efficiency during fabrication. The goal of DFM is to reduce manufacturing costs and avoid costly disruptions without sacrificing quality or performance. DFM saves OEMs significant time and money. Companies are often in a rush to get a new part fabricated so it is tempting to shorten – or even skip – the DFM process. However, it is important to keep in mind that changes to the design become exponentially more expensive and time-consuming to implement as the product advances through the life-cycle. A thorough DFM upfront will allow optimizations to be made or issues to be resolved before the changes significantly impact the project timeline or budget.

About ABS

Established in 1971, ABS Machining has grown to become the recognized global leader in large machining, fabrication, and assembly for OEMs. The key to our success has been exceptional people, unparalleled facilities, and an unwavering commitment to quality. Our people are experts in their given field. Their expertise is matched only by their passion for serving our clients. We continue to invest in our people with education programs, cross training and in our internal accredited apprenticeship center.

Our facilities are state-of-the-art and we are equipped to serve our client’s requirements in:

Our massive fleet of machines and automated welding systems has delivered solutions to the most technically challenging projects. Our commitment to maintaining unparalleled facilities is evidenced by our renowned continuous capital reinvestment initiatives. Our commitment to quality goes well beyond our ISO 9001:2015 Registration. From the inception of all programs, ABS quality professionals work closely with each customer to ensure all their unique requirements are met or exceeded. It is this commitment that has positioned ABS as a strategic supplier to leading OEMs worldwide.