Using Thermoplastics for Hat Making

Working with Wonderflex®

Some of the most exciting modern materials in millinery are thermoplastics. Working with thermoplastics can add a new dimension of design to your creations. They are often used for cosplay and costume construction. They can be painted, are water-resistant and are strong.

There are a variety of thermoplastics available, with a range of hat-making applications. We have already looked at using Fosshape® for hat blocking and how its fabric-like texture resembles buckram when hardened. Harder sheet thermoplastics, like Wonderflex®, can be great for millinery use, as well.

Sheet thermoplastics come in large, hard panels of plastic. They are available in a variety of colors and thicknesses and each variety has its own molding point temperature. A heat gun can be used to shape the sheets, which harden into very strong materials as they cool. Different types of thermoplastics will retain heat for different periods of time, making some easier to mold than others. For safety, wearing heat resistant gloves will protect your hands when working with these materials.

Wonderflex® World is one of the major producers of thermoplastics for hat and costume making. They manufacture both Fosshape® and Wonderflex®.

hat brim edge with millinery wire

What is Wonderflex®?

Wonderflex® is a sheet thermoplastic that is reinforced with a gauze fabric. This means that it will stretch on the bias when heated. The top side is smooth and the material can be cut with a knife or scissors. It bonds to itself and other materials, such as Fosshape®, paper, wood, fabric and foam.

Wonderflex® has an activation temperature of around 150°-170° F (70°-80° C) and quite a slow cooling time. This means that you have 2-3 minutes of sculpt time before the thermoplastic hardens and it can be reheated repeatedly.

The gauze reinforcement (shown above) is what makes Wonderflex® different from other sheet thermoplastics. Becuase of this, it is very strong and tear-resistant and has more stretch, so it is easier to thin and manipulate for detail work. Wonderflex® also has a built-in adhesive that will not stick to your hands (although using an aluminum foil lining is still a good idea if you are shaping it over a mold).

Another exciting thing about Wonderflex® that is cold waterproof, so you can make millinery which can be worn in the rain! Just remember, hot water can soften this thermoplastic material.

3 Ways to Sculpt Wonderflex® for Millinery

  1. The easiest way to shape Wonderflex® is to block it with your hands. This can be done completely freeform or on a hat block, dolly head or any other household object. A cardboard tube was used to create the Wonderflex® Spirals shown above, for instance. If you have a high heat tolerance you may be able to work bare-handed (once the material has cooled slightly). However, for safety, wearing heat resistant gloves is highly recommended.
  2. Using a positive mold is another way to make unique millinery shapes. A positive mold can be created by cutting a shape from foam. Cover the foam shape with electrical tape and then sculpt the Wonderflex®  over the shape. This will make a lightweight shape which can be painted or decorated.
  3. A negative mold – or hollow shape – can also be used. Silicone flower molds, for example, would work well. Simply push the Wonderflex® inside the mold to make hollowed trims and headwear.
Wonderflex® for hat making

Moving Forward with Wonderflex®

Recently, Wonderflex® Pro was released. Unlike the original, this new material does not have the gauze reinforcement, so it can be molded into finer details and more complex shapes. It also has a glossy side which makes painting much easier.

A milliner’s life is full of trial and error experiences to learn hat making techniques and discover which materials you like best. Thermoplastics like Wonderflex® are fun to play and experiment with. They can help you create truly one of a kind millinery trims and hat designs for your clients.

Thermoplastics Projects

Click HERE for all Thermoplastics Projects.