Working With Thermoplastics
Working with thermoplastics in the production of orthotics and prosthetics can sometimes be tricky. Often, the practitioner is working with very hot, sticky materials in a very tight time frame. Also, since different materials have different characteristics, combining materials can sometimes yield unexpected results. It is important to know the materials which you are using. Before using a new material, you should determine the following:
Keep the following in mind when fabricating devices using thermoplastics:
- How long should the material be heated, and at what temperature?
- Is the material autoadhesive (i.e., will it stick to itself when it is hot)?
- Will the material expand or shrink when heated? Will this change in dimension affect both length and width of the piece being heated?
- What adhesive will perform the best in combining the materials being used?
Keep the following in mind when fabricating devices using thermoplastics:
- Always use a turbo-convection, convection, or infra-red oven when heating materials. A standard oven will not heat materials evenly, and damage to the material and/or the oven may result.
- Oven temperatures vary. Test your oven temperature before heating materials, and test samples of each material to determine exact heating time and temperature.
- Use a Teflon coated tray or sheet to keep materials from sticking. DO NOT place directly on rack.
- Spray heat protective gloves with USDA approved silicone spray to keep materials from sticking to you when removing from oven and placing on cast.
