When you're sourcing plastic injection moulds, you'll have noticed that a lot of mould makers advertise 'lifetime guarantees' for their moulds. Before you jump to the conclusion that you'll be able to get perfect products from this mould tool for the next 50 years or more, 'lifetime' means the life of the mould, not yours. Injection Mould Tool Life stands for the number of moulding cycles a mould can make before it needs to be replaced.
Which factors affect tool life?
Any injection mould will be subject to wear. Wear will occur particularly to ejectors, gates, slides & other moving parts of the tool. Surface finishes such as high polish or sparked finish will also become less defined over time. The following factors affect how quickly wear takes place:
- The material the mould is made of. Soft aluminium moulds will incur much more wear from the plastic material than hard steel moulds. Steel moulds should last for millions of mouldings, but not when certain plastic materials are used - see the next point.
- The material the mouldings are made of. Certain materials can be very abrasive, such as glass filled nylon for example. Other materials are very corrosive and will rust normal steel moulds, so aluminium alloy or stainless steel moulds should be used, or the steel mould should be stainless steel or aluminium alloy plated.
- Mould setter skill. Moulds need to be set up to work in the injection moulding machine correctly. Overlocking, poor tool alignment, excessive ejector stroke, overpressurisation of the plastic material, not enough lubricant on the ejectors are all examples of poor setting which wear any mould down much more quickly than necessary.
- Mould maintenance. A regular bit of TLC goes a long way to prolong mould tool life !
Mould tool life guarantees
So, when you're sourcing an injection mould tool, make sure you check the exact guarantees the mould maker has in place. Here at Toolcraft, we make high quality moulds that are suitable for the use they'll be put to. We look after them when we mould from them too. We're very happy to guarantee every tool made by us, when injection moulded by us, as follows:
- Moulds made of P20 steel - guaranteed to 300,000 mouldings
- Moulds made of H13 steel - guaranteed to 500,000 mouldings
- Moulds made of 7000 series Aluminium - guaranteed to 30,000 mouldings (but this will reduce for aluminium mould tools with mechanical moving parts and those where metal inserts are loaded in and out of the tool).
Does that mean the mould has to go in the bin when these numbers are reached? Of course not. A well-made tool may last many times its original guaranteed lifetime, just like your washing machine might now be 10 years past its 1-year guarantee. Repairs may be needed, or parts may need to be reinforced, but the mould tool is likely to serve for many more years. At Toolcraft, the craftsmanship is guaranteed.
To read more mould tool advice, have a look at our injection mould advice pages. And if you're ready to source an injection mould of the quality you should expect,