Tech Tips

Choosing the Right Mold Classification Saves You Time and Money

Choosing the Right Mold

One of the first things we’ll consider in quoting the mold is the right class mold for your project. We can determine the best mold class based on the tolerances allowed on your prints, the approximate number of cycles your project requires and the budget you have to work with.

To help you with this, we’ve listed a few of the classes of molds with the estimated number of cycles the mold can produce along with a brief description of the mold.

Please note, even though each class has its own unique mold requirements, there are a few things that you will want to have on all molds, regardless of the class.

Some of these things are:

  • Mold designs to be available for review and approval prior to start of construction.
  • Complete set of mold drawings to be supplied with all finished molds.
  • All molds and inserts (with the exception of prototype) to have adequate channels for temperature control.
  • Mark all inserts with the type of steel and Rockwell Hardness.
  • Vents at the parting line.
  • In multi-cavity molds and/or inserts, all identical cavities are to be individually identified.

Class Molds   

Class 101
Cycles: One million or more
Description: Built for extremely high production.  This is a top of the line mold made with only the highest quality materials.

Class 102                   
Cycles: Not to exceed one million
Description: Medium to high production mold. Good for abrasive materials and/or parts requiring close tolerances. This is a high quality mold.

Class 103                               
Cycles: Under 500,000
Description: Medium Production Mold.  This is a very popular mold for low to medium production needs. This is the most common mold type.

Class 104                   
Cycles: Under 100,000
Description: Low Production Mold. Used for limited production preferably with non-abrasive materials.

Class 105                   
Cycles: Not to exceed 500
Description: Prototype only. This mold will be constructed in the least expensive manner possible to produce a very limited quantity of prototype parts. It may be constructed from cast metal, epoxy or any other material offering sufficient strength to produce minimum prototype pieces.

Class 401 to 404
Description: These molds have similar requirements to the ones listed above, but are built with stronger materials to be sure they withstand running in injection molding presses rated above 400 tons.

Please click here for our complete guide describing all of the above mold class specifications and more…

Until next time,

PS References for this post are based on the standards set in: Customs and Practices of the Moldmaking Industry; Classifications of Injection Molds for Thermoplastic Materials by the Moldmakers Division of The Society of the Plastics Industry, Inc.

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