Flash (manufacturing)

[citation needed] Proper design of mold parting surfaces can reduce or eliminate flash.

Other times, the complexity of the part requires so many mating pieces with such precise geometries that it is almost impossible to create a perfect fit on every impression.

[3] The process of removing flash, known as deflashing, is commonly performed via cutting, breaking, grinding, or tumbling.

It is very typical for molders to have their operators trim flash with hand tools at the molding machine between cycles.

Many molders and OEMs seek out the use of batch processes including vibratory tumbling, cryogenic deflashing[4] or media blasting to remove unwanted flash from large batches of parts.

Flash, center, on a molded plastic laundry basket. Plastic has filled an area that should be an empty space, probably by seeping through a gap where the molds were not clamped sufficiently close together.