Nesting Fundamentals: Preventing Part Tipping in Laser Cutting

September 25, 2024

As highlighted in The Fabricator’s article “Nesting Fundamentals for Laser Cutting Stability,” achieving stability in laser cutting requires a deep understanding of nesting fundamentals and how decisions made during the nesting and programming phases can impact the entire manufacturing process. With the increased use of fiber lasers in metal fabrication, ensuring parts remain stable during cutting is crucial to preventing head crashes and production stoppages.

What Causes Parts to Tip and Bow?

In earlier days, when shops transitioned from punch presses to flying-optic lasers, parts often remained tabbed in place until they were evacuated or removed manually. However, with flying-optic lasers, the sheets no longer moved, which introduced a new variable: the position of the support slats. As Mike Boggs, Vice President of Sales and Marketing at Striker Systems, points out, understanding the basics is critical, especially with the retirement of many experienced operators.

The primary cause of parts tipping during laser cutting lies in their size, shape, and position relative to the machine’s support slats. According to Doug Wood, Sales Director at Sheet Metal Solutions North America, these factors are crucial in maintaining process stability. Slats are generally placed 2 to 3 inches apart, depending on the machine model. If a part or an internal slug has a dimension smaller than 6 inches, it may only rest on a single slat, increasing the likelihood of tipping.

Slug-Destruct Sequences

To mitigate the risk of parts tipping, implementing slug-destruct sequences can be beneficial. By cutting slugs into smaller pieces, they can fall safely through the slats, reducing the chance of jamming or tipping. This is especially useful for parts with larger cutouts that may be prone to instability.

Additionally, the condition of the slats themselves plays a significant role. If slats have not been cleaned or are unevenly worn, they can cause the sheet to sit higher on certain teeth, leading to increased instability. Regular maintenance of slats can help prevent these issues and contribute to a more stable cutting process.

Managing Part Bowing

While smaller parts are more likely to tip, larger parts—especially those that are long and thin—can bow upward, disrupting the cutting process. Ideally, material designated as “laser flat” should have equalized stresses to minimize bowing when cut correctly. However, if the distortion level of the material is unknown, programmers might need to tab parts in place to maintain stability during cutting.

By carefully considering the nesting of parts and the positioning relative to the slats, fabricators can reduce the risk of parts tipping or bowing. This not only enhances the stability of the laser cutting process but also improves overall production efficiency and reduces downtime.

Click here to learn more about American Metal Fab’s laser cutting services and how we ensure optimal stability and precision in our cutting processes.