In deciding between plastic thermoforming and injection molding for your next project, there are several important factors to keep in mind:

  • Tooling costs for thermoforming are significantly lower than tooling costs for injection molding.
  • Thermoforming, particularly pressure forming, is more cost effective for very large, thin-walled parts, where the tooling costs would be prohibitive with injection molding.
  • Pressure forming can duplicate the appearance of an injection molded part on the mold side of a thermoformed part. This includes the ability to form in a finish texture.
  • Pressure Forming can achieve highly cosmetic finishes, providing the look and feel that meets the end user’s expectations and is similar to the finish of an injection molded part.
  • Increased flexibility in design and engineering
  • Pressure forming and thermoforming molds are easier to modify than injection molds. Since most trimming is done with a 5 axis, CNC router, many secondary trim adjustments require nothing more than a programming change. In addition, aluminum, thermoforming molds are much easier to modify than steel injection molds.

Thermoforming applications often also use painting and secondary assembly in the production of value-added parts. In the end, the best way to decide how to proceed is with the assistance of a trusted, knowledgeable plastics processor. We have put together the following checklist to help you determine whether thermoforming or injection molding is right for you and welcome the opportunity to discuss your needs in more detail. Please feel free to contact us to do so.

Engineering Checklist

How far into the design stage is the project?
If you require design assistance or would like to iterate through various options, thermoforming can offer a more flexible and cost effective design process. This is useful in new or prototype parts that don’t benefit from using prior production experience to modify future designs.

What is the expected production size?
Large parts and low volumes favor thermoforming, while small parts and high volumes favor injection molding. Due to the lower tool costs involved in thermoforming production can typically be initiated with lower capital investment. We have many parts than run with hundreds or low thousands of parts per year that are cost effective as thermoformed parts.

What is the expected size of the finished product?
Tooling for large parts is more cost effective when thermoforming as compared to injection molding. When producing large parts, thermoforming is usually the clear choice if initial cost is a consideration because tooling for injection molding is significantly more expensive than thermoform tooling for large parts.

What is the expected delivery timeframe?
Time to market is quicker with thermoforming. Typical lead time for thermoform tooling and samples is in the 6-8 week timeframe.

Are there any specific material requirements or considerations from a design perspective?
If unique materials are a key factor we can work to find the right choice. We’ve worked with a wide range of material types and vendors over the years. We can use our knowledge developed through experience to guide you in the right direction. We can help find the material that works as well in production as it does in design.

Universal Plastics’ engineering support staff can walk you through the design and manufacturing of your part to ensure the best geometries and most efficient processes to meet your bottom line requirements. If your project requires injection molding, we can identify a Universal business partner to meet your needs.

Put our plastic expertise to work for you — call at 800-548-8090 to begin the process.