THERMOFORMING TROUBLE SHOOTING GUIDE
Incomplete forming
Excessive sheet sag
Non-uniform sheet sag
Non-uniform pre-stretching
Non-uniform wall thickness
Sheet pulling out
Bubbles, blisters or pits
Scorching, degradation
Whitening of formed part
Blushing
Loss of embossing detail
Webbing or wrinkling
Chill marks, drag-off lines
Surface marks
Pinholes/pimples
Shiny streaks
Shrink marks
Part warpage and shrinkage
Plug sticking
Mold sticking
Sheet tearing during forming
Part cracking
Plug Sticking
Probable Cause
Potential Solutions
1. Plug too hot.
1. Reduce plug temperature.
2. Use mold release agent or lubricant.
3. Coat plug with Teflon resin.
4. Cover plug with wool felt or cotton flannel.
5. Utilize syntactic foam plug.
