Here are some often-asked questions that may help you understand the thermoforming process, and Waveform Plastics. Should you have any questions, feel free to contact us at any time, at info@waveformplastics.com.
1. What is thermoforming and vacuum forming?
2. What are the benefits of thermoforming?
3. What parts are a good "fit" for thermoforming?
4. What do you need from me to make a part?
5. Is tooling (the mold, in this case) expensive?
6. What do you make molds from?
7. What's the difference between a male and a female mold?
8. What is a typical minimum run (part quantity)?
9. What's the typical lead time?
10. Should I thermoform or injection mold my part?
11. When thermoforming a part, why can only one side be controlled?
12. What types of plastic can you form?
13. What material thickness can you form?
14. Where can you ship to?
15. How do I get a quote on a part?
16. Where can I find answers to my other plastics and thermoforming related questions?
1. What is thermoforming and vacuum forming?
Thermoforming is the process of heating a sheet of plastic material, and using pressure to shape it using a mold. Vacuum forming refers to the use of vacuum to force the plastic into the shape of the mold. We also do pressure forming, which, as you might guess, uses pressure, along with vacuum, to force the plastic into the mold cavity. Each type of forming has it's own specific advantages. To learn more about the thermoforming process, see this guide (Adobe Acrobat pdf format). 
2. What are the benefits of thermoforming?
Thermoforming is efficient and very cost-effective for the production of many plastic parts depending on the part size, shape, and quantity. Up-front costs are usually much lower, and lead times to tooling and production are generally much shorter than other processes such as injection molding. Temporary tooling offers an inexpensive short-term test for design issues and product market acceptance.
3. What parts are a good "fit" for thermoforming?
Large panels, housings, enclosures, and other similar parts are ideal for thermoforming. Tooling costs for these parts is considerably less than for injection molding, which due to the large part size may have prohibitive tooling costs. Parts with features mostly confined to one side of the part are best suited to thermoforming, but it is often possible to implement or add features to the uncontrolled side during trimming, fabrication, and assembly.
4. What do you need from me to make a part?
We've started from a drawing on a napkin! If you have a concept, then we can create a design, including CAD models, renderings, and detailed drawings. If, on the other hand, you already have a CAD model or design, we can start from that and create molds and other tooling that will allow us to make the finished product. Our services include everything from design to prototypes to production, and we can do as much or as little as you need us to do.
5. Is tooling (the mold, in this case) expensive?
The molds used in thermoforming are designed based on a variety of factors - life expectancy, finish, complexity, and tolerances, to name a few. Generally speaking, tooling for thermoforming is much cheaper than that for other processes, such as injection molding. Molds can be as cheap as a few hundred dollars, depending on the specific requirement. Don't be scared away by up-front costs. Thermoforming can be extremely economical, especially for low to medium volume applications.
6. What do you make molds from?
Production molds are typically cast or machined from aluminum. Deeper molds are usually cast, while shallower molds may be machined directly from a block of aluminum. Aluminum molds can be temperature controlled, which allows tight tolerances, better detail, and shorter cycle times (which translates into a lower cost part). Molds may also be made from various composites which offer short or medium life and easy machining. For prototypes or lower quantity production runs, we'll often make a mold from varying densities of polyurethane board (such as Renboard or Prolab). For prototypes, we can also use medium density fibreboard (MDF), a wood product.
7. What's the difference between a male and female mold?
The decision to use a male mold or a female mold depends on the shape of the part, where tolerances are important, surface finish, mechanical requirements of the finished part, and many other factors. With a male mold, the plastic is stretched over the mold, and then vacuum is applied to draw the plastic down onto the surface of the mold.
With a female mold, the plastic is drawn down into a cavity by the vacuum.
8. What is a typical minimum run (part quantity)?
There are two minimums: production and material. Production minimums vary greatly, based on setup times and part complexity. We'll do just a few parts if needed, especially for prototyping. There is really no production "minimum". Materials also affect minimum quantities. If we can use a stock material, then there is typically no minimum quantity. However, if you require a specific colour, or have special material requirements, minimum quantities are often based on a minimum extrusion run, typically 2500 to 5000 pounds.
9. What's the typical lead time?
Simple prototypes are often prepared in two to three weeks. Again, this can vary, but we do try to minimize prototype turnaround to keep your design cycle short. Production lead times can vary based on material requirements and availability, and quantity. From approval of a prototype, typical production lead time is from as little as one week to a month or two for more complex parts, or in cases where production tooling needs to be fabricated.
10. Should I thermoform or injection mold my part?
Both process are unique, and offer specific advantages and disadvantages. Thermoforming typically has a lower up-front cost, while injection molding is ideal when you're producing hundreds of thousands of parts. Look here for a more detailed comparison.
11. When thermoforming a part, why can only one side be controlled?
The mold defines the shape of the plastic, and tolerances can be controlled on the side of the plastic that contacts the mold. The opposite side, away from the mold, is predictable, but not controlled, because the plastic will stretch around the mold and produce varying thicknesses. There are a number of techniques that we use to minimize this effect, when it's important.
12. What types of plastic can you form?
There are many plastics that can be thermoformed. Many are designed specifically for thermoforming. You can choose from a wide range of engineering plastics to precisely meet your job requirement. Just few of these materials that we work with include:
- Polyethylene
- Polystyrene
- Polypropylene
- ABS
- T.P.O.
- Polyester
- Acrylic
- Polycarbonate
- Plastic alloys
13. What material thickness can you form?
We typically use materials in the 0.040" to 0.500" range. While we don't typically form materials thicker than 0.500", we can machine parts from thicker plastics on our in-house 3- and 5-axis CNC routers.
14. Where can you ship to?
We have customers throughout North America. If you require overseas shipment, let us know, and we can probably arrange that, too.
15. How do I get a quote on a part?
Complete our online quote request form, or contact our sales staff for assistance.
16. Where can I find answers to my other plastics and thermoforming related questions?
Contact our staff for answers to any questions you may have!
Coming soon: Glossary of terms.
