I'm prototyping a hardware that involves many thin walls to bend around curves and such, so it needs to be flexible, cheap, and also transparent. It may also be the same plastic used in a production version.

The only example I can think of is the plastic you find around the inside of a new dress shirt collar. (McMaster Carr doesn't seem to have anything like it, except polycarbonate, which seems expensive and overkill; surely I'm thinking of a much cheaper plastic. Maybe PP, but not finding enough info to confirm, or find out where to get some in that form.) I almost went with transparency rolls for transparency projectors, but it's too thin/flexible (5 mils).

  • $\begingroup$ You can heat up acrylic and bend/form it. Polycarbonate is a good option as well, but more expensive. $\endgroup$
    – GisMofx
    Commented Oct 10, 2018 at 17:02
  • $\begingroup$ I had a similar application (a visor) which successfully used styrene sheet. It is opaque and available in various thicknesses. I would look on a popular Asian site for resellers. $\endgroup$ Commented Oct 12, 2018 at 3:38
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    $\begingroup$ PETG has the lowest thermoforming temperature of all the "engineering" plastics . You can get samples from McMaster -Carr. $\endgroup$ Commented Oct 12, 2018 at 4:04

1 Answer 1


Polyester film / PET / PETE, according to McMaster-Carr support, is a clear, flexible, inexpensive plastic, and is the type found around the inside of a new dress shirt collar.

It's minimum cold bend radius (no heating necessary), at least of certain PET materials, can be approximated from its thickness as R=150T where T is the thickness.


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