since 1953

Plastic Injection & Rotational Molding

For more than 75 years First Plastics has been in Leominster, MA delivering high-quality plastic manufacturing services for commercial, industrial, and residential markets.

Wide Range of Machines

From 250 to 1650 tons, suitable for various project sizes.

Large Shot Capacity

Up to 356 ounces (22.5 lbs) for substantial production needs.

Advanced Technology

We have hot runners and core pulls for precision and efficiency.

Full-Service Support

Tool design, secondary machining, DFM analysis & more.

The #1 choice for all of your plastic manufacturing needs

For all your plastic manufacturing needs, choose First Plastics, where over 20 molding machines and 75 years of industry expertise converge to deliver exceptional results.

Injection Molding

First Plastics employs 20 injection molding machines, some of which are the largest in the Northeast! With 250 to 1650 ton clamping force, a max shot of 356 oz (22.5 lbs), hot runners, core pulls and more we are the best choice for all of your injection molding needs.

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Rotational Molding

First Plastics is home to multiple rotational molding machines, like the Rotoline CR 3.10, one of the only rotomolding machines available to businesses for custom work in the Northeastern United States. Ideal for creating complex, hollow parts, our rotomolding process offers low tooling costs and exceptional design flexibility.

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Assembly & Decoration

First Plastics also offers a suite of value-added services to enhance your products. Our capabilities include advanced design support, precision machining, specialized welding, thorough leak testing, and custom packaging. We ensure high-quality, reliable, and ready-for-market solutions for all your manufacturing needs.

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Additional Services for Superior Plastic Manufacturing

Design Support & DFM Analysis

Optimize your products for manufacturability, longevity and ensure a efficient production.

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Secondary Machining Drilling & Tapping

Enhance your molded parts with our secondary machining services such as drilling, tapping and more!

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Component Assembly Services

Streamline your production process by combining multiple parts into complete, ready-to-use products.

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Water Leak Testing

If you have a product that will be in the water, our leak testing is essential. Ensure the integrity of your product and preventing any potential leaks.

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