When it comes to the cutting and steel-rule die trimming of polyester thermoforms, we have to consider several obstacles and difficulties that we may be faced with. Polyester is harder to cut than traditional thermoforming materials for several reasons including:

• Material hardness is noticeably greater than the traditional PVC
• Quick knife dulling
• Polyesters require roughly 1.5 times the tonnage per linear inch of cut as compared to PVC at similar machine conditions
• knife travel is required at 100% to complete a clean cut, unlike other materials that require 50%-75%

Although it may be harder to cut and trim polyester thermoforms, it is well worth it. Using polyester results in benefits such as producing products with a superior aesthetic finish (higher gloss and smoother surface). Below are some tips which will aid you in mastering the art of cutting and trimming polyester thermoforms.

• Sharpen knives more frequently than on PVC tooling
• Make sure the flange width provides enough material (preferably 1/4 inch) to have good lay flat and be out of the areas close to the blister cavity radius where some residual thermoforming stress may be present
• Bring heat to the material either through a heated backer plate or a heated knife. The softening of the material immediately extends knife wear and regains full use of traditional PVC tool configurations

To overcome issues that you are experiencing with cutting and trimming polyester thermoforming film, try the above suggestions and see results.