Terminology - F

  • FILLET: A narrow, concavely curved strip of rubber at the angle where the rubber and insert meet in a molded rubber product.
  • FINISH: The quality or the appearance of the surface of a rubber product.
  • FISSURE: A split or crack in a cellular material.
  • FLASH: Excess rubber on a molded product, resulting from cavity overflow at the parting lines where the mold sections are separated. Flash has two dimensions — extension and thickness. Flash removal can impact part costs significantly, allowing for the widest possible flash tolerance will help contain costs.
  • FLATNESS: The deviation from a true plane or straight edge.
  • FLUOROCARBON POLYMER: Fluorocarbon (FKM) is often called by its trade name Viton®. It has excellent temperature range to 400°F, compression set, and oil resistance. This polymer performs well against ozone, UV, and oxygen, and is resistant to many chemicals and acids.