Pros and Cons of Thermoforming
In vacuum forming or thermoforming fabrication, the material is just as important as the mold. If a lower-quality plastic sheet is used, the end product could be compromised. The color of the sheet could be uneven and inconsistent. Unpredictable melting could occur, causing irregular gauge thickness. Longer curing and drying could add operation time and cost to the fabrication process. In other words, having the best vacuum formable plastic sheet will always yield the best-finished product.
In short, vacuum forming is a stripped down, simpler adaptation of thermoforming. With vacuum forming, a heated, pliant plastic sheet is stretched on top or inside of a mold. The formable sheet then conforms to the shape of the mold with the application of a vacuum to ensure the plastic fills the mold, tightly and neatly. Once the sheet is formed, the vacuum is released, along with the now-formed plastic sheet.
Vacuum forming is ideal for prototyping and manufacturing parts with a shorter-run production output due to being an easy and economical operation. It is also an outstanding way to fabricate more shallow molds without the higher operational costs associated with thermoforming. Newer, technological advances have allowed vacuum forming with deeper molds, as long as the formable sheet is of higher quality and is mechanically stretched before application to the mold.
When selecting the material for your project, forming plastic is an ideal option. Vacuum formable plastic sheets, usually made of PVC (Polyvinyl Chloride) are designed especially for the vacuum forming or thermoforming process. They can withstand heat application without melting or breaking down. They are also highly regarded for their ease of processing and are inexpensive in comparison to other sheets. Be sure to choose a plastic or PVC sheet that meets your specific requirements, such as thickness, color, surface texture, and overall size. Look for a product that offers precise gauge control and consistent color with lot-to-lot traceability. This way, there will be no differences between manufacturing runs.
There are a variety of applications that benefit from both vacuum/thermoforming and formable plastic sheets. The production of kiosks and automated teller machines include external plastic structures that accommodate delicate, internal mechanisms securely and with branded aesthetics. Since the formable sheets are highly customizable, medical device housing and electronic equipment cases can be properly fitted for a precise fit and appropriate protection. On a smaller scale, electrical components are a perfect application because of the inherent flame retardance of the formable plastic sheet material.
If you are considering your options for a small run of manufactured molded parts or experimenting with a prototype, vacuum forming/thermoforming with vacuum formable plastic sheets is an excellent choice. While the manufacturing process itself is straightforward, the selection of an industry-proven formable sheet will provide high-performance durability without cutting into your bottom line. Be sure to choose a high-quality formable plastic sheet that will hold up to the demands of your next project; you will have a consistent, reliable end product every time.