Toolmakers & Toolmaking
The first known tools were stone implements made by the earliest humans and through the centuries the art and craft of toolmaking has developed alongside technological and material advancements.
There is still a requirement for the crafting skills of a toolmaker but much of the tooling made now involves a level of automation.
The modern manufacture of moulds and dies requires a high degree of accuracy and the tool materials are hard. There is also an increasing demand for complexity and surface finish in the mould cavity. The body of the tool carries cooling channels, cooling the mould after filling to speed up the production curing cycle time. Modern manufacturing methods can be used to generate these channels conformally to the cavity profile, further speeding up the efficiency of cooling to reduce cycle times and optimise process efficiency.
Industry4 – the 4th industrial revolution – is at the heart of modern tool making. Designs are developed in 3D CAD as ‘digital twins’, allowing the simulation of the moulding and product performance prior to committing to the cost of making the tooling. The combined use of Finite Element Analysis (FEA), Computational Fluid Dynamics (CFD), and mould flow software provides an accurate depiction of process and product allowing designers to optimise in a virtual environment. The design data and accuracy definitions are sent electronically to the machining centres digitally and the tooling can be carried out in a lights-out facility with minimum manual intervention.
As products continue to increase in their complexity and surface finishes and accuracy specifications push the limits of what is possible the demands on tooling and the skills of designers will be tested to the limits.
Press tooling is a term used to define a metal tool used to shape or cut metal sheet. In its simplest form the tool may punch out a shape from a sheet of metal or fold the sheet into a prescribed profile. The press machinery will typically be hydraulic, pneumatic, or mechanical – terms describing the method of applying force to close the press.
Where the tool is designed to punch out a shape the operation can be described as blanking, piercing, or trimming.
Where the tool deforms the sheet or billet it may be described as a bending, forming, or forging operation – terms defining the effect on the workpiece material.
Mould tools are used to generate plastic components, the liquified plastic or polymer is pushed under pressure into a cavity to make a part. These mould tools are used across the world to generate mass produced plastic components on a massive scale.
A modern moulding tool is durable and highly efficient. The principles of design for material flow and cooling of the tool are optimized to minimise cycle time. The use of multi-cavity mould tools multiplies the output from the moulding process.
Pattern making is the process of producing a replica of an object. In manufacturing environment this production of a dummy is to facilitate a moulding process. The pattern/dummy creates a form shape and is then removed, and the component material substituted. A simple example of this process is vacuum casting where a pattern is placed in a vat of liquid silicon, the silicon is left to set and then is cut open to remove the pattern. Under vacuum conditions a moulding polymer is introduced into the silicon mould, after curing the moulded component is removed. There are many variants of processes using pattern making, in many the pattern is removed intact but in some the pattern is sacrificial. Pattern making is used extensively in metal casting processes, the pattern creating cavity in the sand mould for placement of cores and the ingress of metal.