What are the most important factors in toolmaking

We have learnt a thing or two about design for manufacture, toolmaking and injection moulding over the years and we endeavour to share this knowledge to help optimise the injection moulding process. The mould tool is the key element in the injection moulding process, and a big investment, so it is vital to get it right, first time.  The process begins with product design and design for manufacture to ensure the tool is designed to produce products that are easily and economically manufactured saving on cost, raw material and energy consumption. 


To maximise performance and deliver value for your production, the correct mould tool material must be specified from the outset. The most commonly used mould tool materials are:


  • Aluminium - Suitable for low-volume projects involving general-purpose /non-aggressive plastics (resins) PP, ABS, PE and nylon.
  • Pre-Hardened Steel (P20) - The most widely used semi-hardened tool steel, good for medium-volume projects.
  • Fully Hardened Steel (H13) - Commonly used for high-volume projects, complex tools and abrasive materials.
  • Corrosion-Resistant Steel (Stainless) - Used for high-volume projects and a great choice when surface finish is the primary consideration.


The incorrect material choice can lead to ongoing maintenance costs, production downtime and increased production costs.


There are many factors that can affect mould tool life. These include part/tool complexity and thermoplastic material type.  Complex and intricate part geometry can affect tool strength.  Mechanical movements and feed type can increase maintenance requirements. Plastic materials can produce corrosive by-products which impact the lifespan of the tool. Materials with abrasive additives, such as glass-filled, can increase wear on the tool. 


The lifespan of a tool can vary significantly as it depends on the material the tool is made from, the number of parts produced and the type of thermoplastic used, however, a reputable injection moulder should be prepared to offer some guarantees for the moulds they manufacture. Routine tool maintenance and servicing is carried out free of charge for all tools manufactured by us for their entire working life at Rutland Plastics.  More information about tooling and toolmaking is available in our interactive design guide on our website.

Free design guide

Rutland Plastics has produced a free Design Guide to help you with all aspects of designing for plastic injection moulding.
Download free guide


We can provide advice and quotes on anything from a simple sketch to a 3D computer model. Most drawing formats can be handled although we find STEP, Parasolid and DXF translate most successfully.