Cutting Scrap by 30% in Injection Molding Without Major Investments

Jonathan Gaylord
Sep 3
3 min read

For many injection molding facilities, scrap remains a hidden profit killer. Leaders often gravitate toward expensive automation or new equipment to tackle this issue. However, many scrap problems can be resolved by rethinking processes, enhancing staff training, and committing to preventive maintenance.

The Real Cost of Scrap

Scrap is much more than wasted resin. It disrupts cycle times, consumes machine capacity, and complicates rework efforts. In a facility with a 5% scrap rate, operating at $10 million can lead to an astounding $500,000 loss each year.

These financial implications extend beyond immediate losses. Increasing scrap rates influence the entire production workflow. Longer cycle times mean machines aren’t optimized, leading to reduced overall efficiency. This inefficiency not only impacts profitability but also affects delivery times and customer satisfaction. For example, if a customer doesn’t receive their order on time due to production delays, the company may lose future business.

Why Scrap Happens

Multiple factors contribute to elevated scrap rates in injection molding. Common issues include:

Lack of preventive maintenance
Inadequate staff training
Outdated cooling and drying systems
Absence of validation programs

Preventive maintenance, often overlooked, proves crucial for smooth machine operation. Neglecting maintenance can lead to malfunction and increased scrap. If a molding machine breaks down due to inadequate upkeep, the resulting downtime can lead to production delays and excess scrap. Similarly, relying on informal training may lead to loss of critical procedures, resulting in inconsistent production quality. A study showed that structured training can improve production efficiency by 15%.

Quick Wins Before Big Capital

Fortunately, several practical strategies can help injection molding facilities reduce scrap without significant investments. Here are some actionable solutions:

Implementing Structured PM Programs

Developing a structured preventive maintenance program can drastically reduce scrap rates. Regular maintenance checks keep machines running effectively. This proactive approach not only prevents malfunctions but also extends the lifespan of equipment.

Basic Scientific Molding Principles for Staff

Training staff in essential scientific molding principles enhances their understanding of the molding process. Improved knowledge empowers employees to spot potential issues before they escalate, ultimately leading to reduced scrap.

Material Handling Improvements

Enhancing material handling systems—particularly drying and feeding mechanisms—can lead to significant reductions in scrap. For instance, ensuring proper drying of materials before processing can reduce defects by as much as 20%.

Cycle Time Validation for Every Mold

Validating cycle times for each mold is another effective strategy. Knowing the optimal cycle time allows facilities to minimize the risk of scrap production due to incorrect settings, which can address issues before they escalate into larger problems.

Case Example

In one facility assessment, we pinpointed opportunities to cut scrap by 30–40% through comprehensive staff training, cooling system upgrades, and cycle time validation protocols. These efforts projected annual savings of $400,000. This case demonstrates that substantial improvements can occur without major capital investments.

By emphasizing training and process enhancements, the facility empowered its workforce and improved operational efficiency. The cooling upgrades maintained molds at optimal temperatures, significantly reducing defect rates.

Final Thoughts

Reducing scrap in injection molding does not hinge solely on acquiring new technology or equipment. By reevaluating processes, enhancing employee training, and committing to preventive maintenance, facilities can achieve remarkable reductions in scrap rates—often by 30% or more.

The financial benefits of minimizing scrap are substantial, and the strategies detailed here can be implemented with minimal investment.

Ready to stop leaving money on the production floor? Schedule your Free Operational Review with Plasteck Consulting and discover how to cut scrap without buying new machinery.