Every injection molder wants to improve overall efficiency and productivity. We want higher quality parts and less waste. More time in production and less downtime.

While mold releases can help prevent many issues that compromise finished parts, these products aren’t as effective on dirty molds.

The truth is that properly cleaned and maintained molds produce better parts, reduce unnecessary downtime from failures, and last longer, saving you both time and money.

So how do you develop the right mold care and maintenance program for your facility? Read on to find out what to look for, what cleaners work best, and how to create a maintenance program that works for your process.

Track the Variables

When it comes to injection molding, every process is a little different. Some manufacturers swap out their molds throughout the production cycle to produce different products. Some manufacture a single product or run a 24/7 operation. Others use complex molds with many nooks and crannies, while some manufacture relatively flat products.

The point is there is no one-size-fits-all solution when it comes to mold cleaning and maintenance. However, there are questions you can ask to gain information for making informed decisions about your cleaning and maintenance routines.

• How many parts do you make on any given mold?
• How many molding cycles do you currently perform until you have to remove and clean the mold completely?
• When do you start to notice buildup or changes in your finished part?

The ultimate goal of these questions is to find the mold-maintenance sweet spot—the point just before you would normally see mold performance deteriorate. This could be when you see a haze develop on the mold surface or when you begin to notice part ejection slowing down.

Performing light maintenance at the mold-maintenance sweet spot allows your mold to maintain quality production for a longer period of time, while reducing overall maintenance needs.

Start gathering the data and see what you find. Then, you can begin working backwards to discover solutions that reduce waste, cut costs, and increase profit margins.

Identify Buildup

Analyzing the residue and buildup that is common to your process can help you determine the best approach to eliminate it.

Resins often contain fillers, release agents, or stabilizers that leave residue behind. That residue could be light oil, a waxy yellow film, grease, white dust, or even rust. PVC resins create hydrogen chloride gases that can corrode steel molds over time. Flame-retardant resins often contain antioxidants, which can degrade steel molds.

Understanding the sources of contamination can help you find ways to minimize it. You’ll also likely find that there are some contaminants you can’t avoid, which could spark changes in your process or help you find products that can eliminate contaminants more efficiently.

Develop a Consistent Mold Cleaning Process

While information gathering is a great first step, it’s also important to establish consistent mold cleaning and maintenance routines to get the best results.

Do different operators use different cleaning processes at your facility? If so, this can result in inconsistent part quality, and even create additional maintenance issues or premature wear and tear on your molds.

That’s why it is so important to define the cleaning agents that should be used and at what intervals they should be applied.

As a general rule, molds should be cleaned before they are placed into production and then again before going back to storage. You’ll want to create guidelines that ensure each operator performs the required cleaning procedure in the same way at each cycle for more consistent mold performance.

Spot Cleaning

If your molds develop buildup during their usual cycle, it may be necessary to spot clean your molds in-cycle. Using the right cleaner here is critical, since fast-evaporating mold cleaners may not remain on hot tools long enough to completely remove all contaminants.

In these cases, using a slower drying mold cleaner can work to your advantage.  Stoner citrus-based mold cleaners are perfect for in-cycle cleaning since they won’t evaporate as readily on hot tools. They also produce very little odor, making them the perfect choice for spot cleaning at operator workstations.

Choose the Right Mold Cleaner for Your Process

Do the cleaning agents you use fail to remove soil effectively or take too long to use? It may be time to evaluate your mold cleaning agents.

Using a slow evaporating cleaner (such as a citrus-based product) will take longer to dissolve contaminants, which can lead to mold or part spotting. However, these products are very effective for in-cycle cleaning since they don’t evaporate immediately, improving cleaning effectiveness.

Fast evaporating cleaners, like Stoner’s Cut Mold Cleaner, are powerful, don’t require a lot of scrubbing, and get into the nooks and crannies of complex molds. These cleaners won’t leave marks from scrubbing or residue on the mold, but they can evaporate too quickly on hot tools, sometimes leading to incomplete cleaning.

Stoner® A497 Non-Flammable Cleaner for Molds has many uses in the molding industry where a strong cleaner is needed for high temperature mold cleaning. A497contains powerful cleaning agents used to remove grease, oil, carbon deposits, and build-up from mold surfaces. This non-flammable mold cleaner contains no trichloroethylene and quickly removes difficult mold build-up, leaving no residue after drying. Removes finger marks and displaces moisture.

The type of mold cleaner you need will depend on your process, the complexity of your molds, and the types of contaminants that need to be removed. If you have questions about the right mold cleaner for your process, Stoner Molding is always here to help!

Monitor Part Quality

After implementing a new cleaning process, it’s important to watch for potential part quality issues that can arise. Some mold cleaners can leave residue on the mold that can affect the appearance of finished products or compromise functionality. To combat this issue, make sure that all of the cleaner is removed prior to putting the tool back into production.

Stoner Molding offers a number of quick-evaporating, fast-drying mold cleaners specifically formulated for injection molding. If you’re looking for a high-performance mold cleaner made with natural cleaning agents, Stoner A500 All Citrus Cleaner is made entirely from highly refined citrus extracts, dries quickly, and leaves no residue behind.

While mold cleaning is often viewed as a hassle that slows down the production line, clean molds produce higher-quality parts with less waste. Properly maintained molds will increase the useful service life of your molds, reduce downtime, and save your facility time and money, increasing productivity and profitability.

Have Questions About Mold Cleaning & Maintenance?

Stoner Molding is always happy to provide answers! We’ve been helping manufacturers mold more parts in less time since 1942. We formulate and manufacture a wide range of mold releases, mold cleaners, lubricants, and rust prevention products designed to optimize your production process and improve your bottom line. Contact us today for a FREE sample!