Design Engineering

Design Engineering



  • Over 50 years of product and mold design experience
  • Domestic and international mold sourcing
  • Expertise in material selection
  • Ability to handle almost any CAD file
EnviroTech Custom Injection Molders has a team of very experienced engineers that provide support for new product development, product design, and on product manufacturability. EnviroTech also provides assistance in resin selection, product testing, and product validation. EnviroTech has worked with multiple customers to leverage value steam best practices and reduce product cost. Designing for part strength and cosmetic appeal can present challenges in injection molding. At EnviroTech, we recognize that these are two of the most important features in a product and want to ensure your complete satisfaction.

To optimize the structural strength of a part, keep in mind the following:

  • Uniform wall thickness – Variations in wall thickness can weaken the part by creating high stress concentrations, uneven shrinkage and sink marks.
  • Remove Sharp Corners – Use a radius to round edges and corners. Leaving sharp edges can create high stress concentration areas and weaken the part.
  • Add reinforcement features – Add gussets, ribs, and bosses to reinforce part features. Gussets should be around 60% – 70% of the parent wall thickness. This helps to avoid uneven shrinkage and sink marks from adding thick masses of plastic. Gussets and ribs are a good method to support walls, while bosses are a good method for supporting holes and other features.

To optimize the cosmetic appearance of a part, keep in mind the following:

  • Surface Quality – Whether you are looking for a shiny, matte, or textured finish, EnviroTech can help you find exactly what you are looking for. Textures can be used strategically to mask sink marks, if they are unavoidable in a particular design.
  • Gate Location – When designing your injection molded part, keep in mind your choice of gate location (where the plastic will enter the mold). Depending on the part, certain locations may improve the overall strength of the part. At the same time, certain locations may improve the overall appearance of the part. Our experts can help you identify the optimal gate location to find the perfect balance between part strength and appearance.
  • Ejector Pin Marks – In general, ejector pins are required to remove parts from a mold. We do our best to make sure pins are flush with the mold surface, dramatically reducing any marks they might leave on a part. We can also help you choose strategic locations for ejector pins to help hide them. Surface textures are another means of masking ejector pin marks.
  • Mold Draft – A proper draft angle is required to prevent parts from becoming lodged in a mold. The draft angle or taper should be 1 to 2 degrees measured from the plane perpendicular to the parting line. This will help new parts leave the mold without being scratched or damaged. The draft angle may vary depending on the surface quality of your part. Our engineers will help determine the ideal draft angle for your parts.

We look forward to helping you optimize your existing products and develop new products. Our skilled Engineering and Technical support teams are ready to answer any of your design questions and help you get quality products to market as quickly as possible.