Injection Moulding wins hands down for multiple production parts.
China moulds in just 2 weeks!
This may be due to the type of evaluation that is required, the number of people involved, or that they are really production items!
Methods can vary but typically the greater the numbers, the closer the prototyping method gets to the production method. For example 50 sets of sheet metalwork would be laser cut and formed and 100 mouldings would be injection moulded albeit with a different level of tooling.
It is worth noting at this point, that we have no allegience to one process, and therefore we can offer unbiased options to ensure you have the right process for your pre production parts as we will now discuss.
Vacuum casting and reaction injection moulding (RIM) occupy the central ground. Whilst requiring tooling, they both have specific attributes that make them attractive to producing quantities of large or complex parts. Vacuum casting can emulate colour and texture in a variety of grades of polyurethane (PU) resin, both hard and flexible.
Similarly RIM requires tooling, but due to the low pressures employed, facilitates the production of larger parts, without the dramatically increasing price of a similar injection moulding.
For injection moulded plastic parts, we now offer a range of tooling options, several of which move this process firmly into the pre- production arena. Leadtimes can be competitive with vacuum casting and depending on quantities, price can be competitive as well. All with the significant upside of having prototypes in production intent materials!
If material requirement is paramount, it may be worth looking at our article, 'I want my prototype in ABS, like the production part. What can you do?'
Then there is additive manufacture (metal and plastic). Most often if parts are being made with additive manufacture in production, then they contain features that prevent alternative manufacturing options. For example lattice structures in the core to reduce weight, or they are the combination of several conventional parts fused together. In these cases there is little chance of employing anything apart from the intended production process.
However, there are times when additive manufacture can be applied very effectively to parts that will be moulded or machined. For example, Laser Sintering (SLS) can produce a few hundred relatively small parts with no cosmetic requirement, very quickly and at an attractive unit cost. Similarly high resolution stereolithography can be used for small batches of very detailed components requiring specific attributes, such as stiffness, in lieu of machining (or DMLS) from metal.
If the requirement is for metal components, these are frequently machined and post processed, as the production items would be, just in significantly shorter leadtimes. Under the pressure of time, CNC machining from solid will often offer advantages over casting and post machining, so long as the geometry permits.
We are here to ensure that you get the best from your prototyping experience. As you can see Plunkett Associates can provide a multitude of options of processes alongside material choice to ensure you get the best possible for your pre production parts.
With no vested interest in any one process, we can offer truly impartial guidance on the options, and support you all the way from initial prototypes through design approval/launch to subsequent tooling and production.
If this is what you are looking for, please give us a call or upload an enquiry here.