Want to make a great product? Make a great tool! (If only it was that easy!)
Tooling is a crucial and expensive item on the manufacturing to-do list. Think about it this way: Each decision you make about the tool is a decision you’re making about your product. But how well do you understand the process of making a tool?
Let’s take a quick look at the process of toolmaking.
Designing the tool is the most critical step in the tooling process. You want to get all the kinks out before any cutting begins because errors are expensive. This is where using a contract manufacturer (CM) offering Design for Manufacturing (DFM) services can really pay off.
First things first: Decide what category of tooling is required
This decision is driven by your anticipated production quantity. You’ll need to figure out the life expectancy of the product first, then work backwards to figure out the tool requirements that will support the product's needs. Your tool will fall into one of three quantity-driven categories:
*Quantities will vary depending on part, material, fabrication, maintenance, etc.
Hard tool or Soft Tool?
This is largely determined by two factors: production quantity and product material.
Urethane is the material of choice for soft tools. They cost less, but have a shorter lifespan and limited features (for example, you might have to sacrifice porosity.) Examples of soft tool processes include:
Using soft tools for small production runs (1,000 to 10,000 parts) can keep your investment low and result in a shorter ramp-up time.
Hard tools are made of long-lasting materials like steel. If well-maintained, high-density injection molding tools could produce up to 100,000 shots for metals or up to 500,000 shots for plastics. Hard tools should be used for:
For smaller production runs, and budgets, aluminum is a less expensive — but much less durable — alternative to steel.
Mold Flow Analysis (for Plastics)
Before a design is finalized the toolmaker makes sure the tool performs as expected.
Benefits of Design for Manufacturing (DFM)
The purpose of Design for Manufacturing (DFM) is to design the part so that it’s easy to manufacture. Working with a CM that provides DFM services will ensure your part isn’t overdesigned and is manufacturable.
Open communication with your CM and a clear understanding of your product’s life expectancy, usage and appropriate materials is essential. Here’s the thing: You could make your product without the DFM process, but why would you? Without any design analysis or optimization, you may very well end up with a non-compliant, cosmetically disappointing product. Why take that risk?
Tool material has a significant impact on performance and life expectancy. Material is determined based on the tool's
The goal is to make a tool as hard and as consistent as possible based on thermal conductivity requirements. For instance, very high-quality materials can withstand the ebb and flow of thermal changes, whereas poor quality materials will crack.
Pro tip: Invest in good quality tool material and you could double the life of the tool.
When You Need a Stronger Material
Sometimes coatings like nickel plating are used to help prolong the life of a tool. While coatings can be helpful, it’s always better to start off with the right tool material rather than depending on coatings, which will wear off over time.
Warning: Using materials with drastically different thermal properties is a bad idea since they will shrink and expand at different rates, creating gaps in the tool.
Your contract manufacturer will send you a PEG (parting line/ejector placement/gate location) design for review before the tool is cut. Carefully review the PEG to understand where these features are located and how the design will affect your final product, both aesthetically and functionally. Your CM should ask for your approval on the PEG before the tool design is finalized and fabricated.
Once the design is completed, the toolmaker begins fabrication. A third party is often enlisted to apply a heat treatment to harden the tool. A heat treatment certificate should be provided and verified. The tool is then shipped to the manufacturer's location.
Regular preventive maintenance is the best way to ensure a long life of excellent tool performance. A regular maintenance schedule should include:
Pro tip: If you have concerns about tool maintenance, ask your CM if the supplier keeps a regular maintenance schedule or log book.
Even with regular maintenance, tools can wear out earlier than expected. The most common reasons for a tool to wear out early are:
Learn more about designing quality tools: