Specify Minimum Wall Thickness, Not Only the Average

The ARM guide says rotomolded parts inevitably vary in wall thickness. A nominal figure describes an average for design calculations, while a minimum figure gives the manufacturer and inspector a more useful lower limit. The guide also notes that increasing shot weight changes both thickness and production time.

Critical areas deserve attention

For a transport case, latch mounts, corners, handles and base contact points are often more important than a single average measurement. Specify where thickness will be measured and which areas can tolerate variation. A thicker shell can also reduce usable internal space.

• Identify high-load and hardware-attachment locations on the drawing.
• Agree on a sampling method and a minimum allowable reading.
• Balance added material against weight, cost and interior volume.

The cover shows an illustrative manufacturing mold detail, not a thickness measurement or performance certification.