SKH Metals BIW Fixture Design Engineer Interview Questions and Answers for Experienced

Shut off angle in molding refers to the angle at which the mold halves meet and close to form a complete part.

• Shut off angle is crucial for ensuring proper part ejection and preventing flash formation.

• It is typically between 0.5 to 3 degrees, depending on the material and part design.

• A larger shut off angle may be required for parts with deep cavities or complex geometries.

• Improper shut off angle can lead to part defec

In pp plastic material, coating is preferred over painting for better adhesion and durability.

• Coating is commonly used on PP plastic material for better adhesion and durability

• Painting is less preferred on PP plastic due to poor adhesion and durability

• Examples of coatings for PP plastic include polypropylene-specific primers and adhesion promoters

Undercut angle in plastic is the angle between the side wall of a mold and the vertical direction.

• Undercut angle is important in plastic injection molding to ensure proper release of the part from the mold.

• It is typically measured in degrees and affects the draft angle required for the mold.

• A larger undercut angle allows for easier part ejection but may require more complex mold design.

• Examples of parts with undercut a...read more

Warpage and sink marks are common defects in plastic parts caused by uneven cooling. Prevention methods include proper gate design, cooling system optimization, and material selection.

• Warpage is the deformation of a plastic part due to uneven cooling, leading to dimensional inaccuracies.

• Sink marks are depressions on the surface of a plastic part caused by uneven cooling and shrinkage.

• Prevention methods include proper g...read more