Slide Products Sticky Situations Enewsletter

Storing Molds For Months? Years? Set Your Alarm.

Mold Storage - Set Your Alarm
spacer image

Tick. Tock. Time is not on your side. There is a limit to how long a mold can sit unattended, even with the best rust preventive.

For example, let’s talk about THAT mold. The mold that sits on the shelf for several months, or even years. Then the customer calls, the order comes in and you pull the mold on schedule to start making parts.

The mold is cracked open and you see it. Rust. A quick prep job is now a mold repair issue. So, what happened?

You are not alone

Slide gets phone calls all the time asking about rust issues. We even received a call asking why molds coated with a 5-year rust preventive didn’t protect the mold after several months. A short discussion and we came to find out they were storing molds outside. Rust preventives are not formulated to handle an outdoor environment.

Set your alarm, check your mold

There are a couple of different timelines, depending on your molding environment, to inspect and protect your mold.

1) If you are storing a mold longer than 6 months

The American Society for Testing and Materials (ASTM) testing method for rust preventives designates long-term rust preventive as being effective for up to 5 years of indoor storage, such as Slide No Rust. If you are storing a mold longer than 6 months, we recommend that the entire mold block (cavity as well as mold base) be protected with an oil-based rust preventive.

Set an alarm for 12 months out

It is also best practice to crack open and inspect any mold stored for longer than 12 months, looking for any signs of corrosion. You should reapply rust preventive product following these inspections to ensure all critical surfaces are protected.

2) Molding gas-emitting resins?

Has your mold been running PVC or any other gas-emitting resin? Be sure to use a rust preventive with protection against not only corrosion due to moisture, but also oxidation caused by the presence of the acidic vapors released by these resins. This would be a rust preventive like Slide’s Acid Vapor Neutralizer.

Set an alarm for 30 days out

To ensure your mold has continuous protection you should reapply the rust preventive that protects against acidic vapors every 30 days to ensure that the acids present in the area around the mold continue to be neutralized.

More tips to protect your mold

As the mold is cooling, apply rust preventive to the mold cavity, the plates and mold base to help prevent condensation from causing rust and oxidation. This is a “dirty” step since the hot mold will likely cause the oils in a rust preventive to liquefy and run. It still protects the mold until it is cool enough to pull and take it to the tool room to break it down. Slide’s Mold Shield is ideal for short-term protection. If you need a food-grade formulation or you are molding medical parts, use Slide’s White Rhino rust preventive.

Now that you are in the tool room, break down the entire mold system to look for gas buildup, color stains, water stains, resinous deposits and any other contamination that might have built up on the mold unit during the production run. Use a mold cleaner and/or a mold polish to remove these contaminants and give you a clean mold.

Now follow the rust preventive guidelines mentioned earlier, based on your storage timeline and indoor environment, and you are assured your mold will be ready to perform with your next order.

Need help with an ejector pin issue or any mold maintenance questions? Ask An Expert at Slide Products; call 1-800-323-6433;

Latest news: Are carcinogens lurking in your mold releases & mold cleaners?


spacer image
spacer image