High Volume Rotomolded Plastics –

From Concept To Delivery


Dowco’s designers and engineers are dedicated to managing your project from sketch, to prototype, to final production for a variety of parts. Our design and engineering teams will help manage the process, keeping your goals in mind. This total support helps maintain competitive pricing and timely shipping.

Dowco Plastics’ highly controlled rotational molding manufacturing process, also known as rotomolding, is a highly-economical way to produce large components. We use top quality polyethylene, PVC, nylon, and polypropylene to manufacture your plastic parts through our four-step process to meet your exact specifications and color.

Rotomolding offers many distinct advantages over other types of molding (such as blow molding or injection molding) including cost savings, short production times, and superior strength.

Unlike other plastic molding processes, our process produces seamless parts with a consistent wall thickness and more material in the corners. This allows our products to absorb shocks and stresses where they are more likely to occur. Enjoy the endless possibilities with Dowco’s Rotational Molding team!

ATV Toolbox
Construction Equipment
Pontoon furniture seat bases

Common Materials:

  • LLDPE – Linear Low Density Polyethylene
    • Most common material used for items like cargo boxes, furniture bases, water tanks, etc. This material provides a high level of durability through more flexible properties and UV resistance.
  • HDPE – High Density Polyethelene
    • This is a harder plastic that is less flexible. It is also highly UV resistant.
  • Crosslinked Polyethelene
    • Used for diesel and gasoline tanks
  • Nylon

Maximum Part Dimensions:

  • Dowco’s largest rotomolding machine can mold parts up to 120″ wide and 60″ tall. Since the machine rotates the part, there are limitations on exactly what will fit. Please contact Dowco to learn more.

Rotomolding offers outstanding flexibility and precision. Complex contours such as metal inserts and flanges can be made right into the walls requiring fewer steps to produce your finished product. In addition, rotomolded plastic eliminates sharp corners and burrs and results in a smooth and seamless product. This reduces the risk of injury for operators.

A wide spectrum of colors are available with rotomolding. There is also no chipping because the color is solid throughout the whole part. Rotomolding offers many distinct advantages over other types of molding such as blow molding or injection molding. The advantages are:

  • Dramatic Cost Savings
  • Short Production Times
  • Easy Modification
  • Superior Strength
  • Ability to Produce Multi-Wall Moldings

Rotational molding is incredibly versatile and is able to handle a vast variety of shapes and sizes. Toys, play houses, drain tile fittings, automotive parts, kayaks, fuel tanks, and park equipment are only a few of the numerous products that can be made. As you can see in the above list, the products produced are only limited to the imagination.

Although the possibilities for rotomolding are endless, the thermoforming method of molding may be what you need. Read on to find out more!


4230 Clipper Dr
Manitowoc, WI 54220
(920) 682-7796


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