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Thin Wall Plastic Injection Molds

Thin wall plastic injection molds are specialized molds that focus on mass-producing plastic parts that are thin and light, such as disposable food savers, storage bins, and 5-gallon pails. The thin wall parts provide product weight reduction, material cost savings, and faster cycle times, which means higher productivity and lower costs per part. A consistent and repeatable thin wall finished product is critical to performance and requires tight tolerances in the mold design as well as expertise in knowledge of plastics and shrinkage.


Thin Wall Plastic Injection Mold Additional Features

Sometimes part geometry creates challenges in molding. When a part’s length of fill exceeds the wall thickness and thickness is less than .080” you could be looking at a thin wall mold — for example, when flow length to wall thickness is greater than 200.

Here are some tips on tool design for thin walls:

  • Consider steel harder than P20, especially when high wear and erosion are expected.
  • Interlocks prevent flexing and misalignment.
  • Cores that telescope into the cavity reduce core shifting and breakage.
  • Heavier support plates with support pillars, typically preloaded.
  • Reduce pin pushing with more and larger ejector pins.
  • No. 2 diamond polish to eliminate part sticking and/or plating.
  • Proper venting is critical.
  • External heated manifolds can help reduce pressure loss in runner systems. 

Don’t change the geometry of your desired part, first talk to us and challenge our innovation.  Contact Us

Thin Wall Plastic Injection Mold Customer Example

A disposable food storage container company was looking for an additional capacity mold based on improved sales volume. They wanted a 12-cavity mold that guaranteed consistent thin wall fill with a fast cycle time. We were able to deliver this mold through our innovative process.

Large Increase in Capacity Example
  • Part Height:  2.015“
  • Volume:  0.439 cubic inches 
  • Material:  PP
  • Shrink: 0.018”
  • Stroke: 2.000”
  • Total mold weight:  7,200 lbs.
  • Eternal Mold Dimensions:  L 23” x W 33” x H 39”
Thin wall plastic Injection
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