5 Types of Mold Classifications

Have you ever received quotes from different custom injection molders that were so far apart, you seriously wondered if they were actually quoting the same project?

Us, too. We’ve been on the quoting end and have questioned the same thing.

When evaluating and quoting a custom plastic injection molding project, it’s important to consider more than just the basic specifications of the project. If a potential vendor is not fully educated in the standards of mold classifications, that company may be presenting a quote that - while it may seem on spec at a glance - is actually nowhere near the quality you’re looking for.

Standard molds are defined by the Plastics Industry Association (PIA, formerly known as the Society of Plastics Industry or SPI). These mold standards are categorized into five classifications to guide quotes and orders into uniform mold types: (click image to enlarge)

While these guidelines are intended to be used as a reference point that is continually evolving, they offer a simplified definition of the type of thermoplastics required for a set production need. This allows for comparing “apples to apples” in the area of custom mold designs.

Class 101 Mold/Tool

• Cycles: One million or more

• Quality: High

• Price: High

• Uses: High quality production and fast cycle times

Class 102 Mold/Tool

• Cycles: Not exceeding one million

• Quality: Medium to High

• Price: Fairly High

• Uses: Parts with tight tolerances and/or abrasive materials

Class 103 Mold/Tool

• Cycles: Not exceeding 500,000

• Quality: Medium

• Price: Mid-range

• Uses: Low to medium production parts

Class 104 Mold/Tool

• Cycles: Not exceeding 100,000

• Quality: Low

• Price: Low to mid-range

• Uses: Limited production of non-abrasive parts

Class 105 Mold/Tool

• Cycles: Not exceeding 500

• Quality: Very low

• Price: Low to accommodate limited number produced

• Uses: Prototypes

Every custom plastic injection molded part has its own unique parameters, and you should consider more than a quick review of these mold classifications. Budget, quality and desired production life are all essential pieces of information that should be discussed with whoever you’re working with to build your mold/tool.

There are benefits to a one-stop shop.

In most cases, there are custom tooling/mold builders and those who actually use those tools to produce/manufacture these custom injection molded parts. When you find a partner who has the knowledge and expertise to do both, it can seem too good to be true.

At FTM Engineering Group, we have the unique combination of capabilities that allow us to both design and build the tooling, as well as manufacture the custom plastic injection molded parts that those tools are made to produce.

Are you working on a project right now and have questions?

Let’s start by having a quick conversation. You can contact us today or go ahead and formally request a quote.