“What is a good material for vacuum forming?”


This is a
popular question received from clients. This question has a rather long answer. Most Thermoplastic materials are thermo-formable, and thus vacuum forming compatible. Some of the most common and easier materials for forming are listed below.

Vacuum Forming Materials:Vacuum Formed PETG Part

  • ABS (Acrylonitrile-Butadiene-Styrene)
  • Acrylic (Plex, Lucite and Acrylite)
  • HIS (High Impact Styrene or Polystyrene)
  • PETG (Vivak or Spectar)
  • Polycarbonate (Makrolon or Lexan)
  • Polyethylene (HDPE or LDPE)
  • Polypropylene
  • PVC or Rigid Vinyl
  • Check with us for other materials that may be available for your requirements

Each plastic material has a variety of different properties, and they form at different temperatures. The Acrylic, PETG and Polycarbonate are normally clear (can be special ordered in colors), however the Polycarbonate may have to be heat dried prior to the vacuum forming temperature phase (depending on thickness).


ABS and HIS both form very well, and are normally White or Black. The ABS normally has a fine texture called Hair Cell on the primary surface, the Styrene is smooth on two sides. On a special basis Styrene and ABS can be run in almost any thickness up to .375″ thick, and in almost any color (minimums apply) and in a huge range of custom run sheet sizes.


While many other materials may be available for special applications and with various improved properties, these are the most commonly available and used materials.


Some of the important factors in choosing a material for your vacuum forming project would be: clarity, strength of finished part, temperature, depth of draw, UV resistance, Flame Retardant Rating, thickness and size range.
Vacuum Forming Mold 300x183 Looking For Vacuum Forming (Formable) PlasticsChocolate Molds 300x200 Looking For Vacuum Forming (Formable) Plastics

Large parts can be produced using this process, for example – Hot Tubs and Pick Up Truck Bed Liners. Also vacuum forming is used to produce very small parts like chocolate molds and numerous packaging applications.

Most vacuum formers started in their garage (or kitchen). A simple vacuum forming ‘machine’ can be produced at very low cost using 2 X 4 wood, peg board, and your shop vac. Obviously this is not the way the above hot tub was formed, but the process is rather simple and is much more an art than a science. We have seen several YouTube videos showing entry level – DIY style vacuum forming machines. Most use the kitchen oven as the heat source and are used to make small chocolate molds, wax molds, hobby parts and more. Many materials can be used in this simple process, and we are happy to assist you with your basic questions of the vacuum forming process.

There is a wide array of materials that can be used, and they have different properties – no one material meets all your needs. Contact us for details on your vacuum forming requirements or with question.

Google+ – Hayden Hess

9 Responses to “Looking For Vacuum Forming (Formable) Plastics”

  1. Great info:The HIS Styrene seems to fit my needs and color is not a factor what is least costly is better. Need . 040 thickness for testing and what sheet sizes i can buy.
    Thanks Philip Biggins

    • Plasticman says:

      Hi Philip,
      Yes, styrene is very inexpensive. The thin material comes in white, but it is easily painted or silk screened.
      We do supply a .040 thickness sheet, and here is the link to check pricing: Styrene Sheet Pricing – the .040″ is listed as 3/64″ thick.
      Please let us know if we can assist further.
      Thank you, Your Plasticologist

  2. Ray Call says:

    The plans for my homebuilt airplane call for 1/8 inch thick Plexiglas thermo formed into a wing tip light lens. The lens will have a compound shape. The plans start with a plastic sheet 8 x 12 inches. It seems to me an acrylic or polycarbonate would work and further, should the acrylic be extruded or cell cast? What material would you suggest? The airplane, if it flies per the plan’s specs, should see 200 mph or more in use.
    Thanks
    Ray

    • Plasticman says:

      Hi Ray,

      Acrylic is the best choice for your inquiry. It is the most rigid of the two, and will form much easier.
      Regarding Extruded versus Cast Acrylic, the answer is Extruded. Much easier to form.
      Can’t tell you anything about how well it will handle the speed, that is a design issue.
      Let us know if you need further assistance.

  3. Chris says:

    What I’m looking to form has been traditionally handled by PETG. The item must be as close to water clear as possible. Current piece thickness approaches 1/8″ (.125). My concern is the expense of PETG. I’ve seen less expensive formable plastics (Lexan, Makrolon, etc), but I do not know they’re forming characteristics / durability / etc. as compared to PETG. Is spending the money on PETG worth it, or can I use a less expensive plastic to achieve similar results? Thank You.

    • Jesse says:

      Chris, the clearest plastic in .125″ would be Acrylic. As we have mentioned before in our blogs–each plastic has advantages and weaknesses. Acrylic is great for displays because it is clearer than glass and has a hard surface so it doesn’t scratch as easily as other plastics. The downside to Acrylic is that it is brittle.

      Lexan and Makrolon are name brands of polycarbonate which is more impact resistant and not as brittle as Acrylic. However, polycarbonate scratches a lot easier than Acrylic.

      PETG can be vacuum formed, looks great and doesn’t scratch as easily as polycarbonate and is not as brittle as Acrylic–so you get the best of both worlds. Yes, it may be a little more expensive, but well worth its value. I hope this helps make your decision easier!

      • Chris says:

        Jesse, Thank you very much for the information. After doing additional research, I learned about “absorption rates” and that some materials need to be dried before than can be used. This, along with the other factors you mention, helped solidify my decision to use PETG. Thank You!

  4. Jesse says:

    Great! Glad I could help Chris!

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