For research and development departments, cutting costs without sacrificing design is a constant struggle. But when it comes to plastic prototypes, using machined plastic parts instead of molds may help companies deliver top design without paying top dollar.

Using molds to make plastic parts can be cost effective when producing large quantities, but when a part is in the planning stages, machined plastic parts might be the best option. They can save manufacturers both money and time.

Why don’t more companies use machined plastic parts for their prototypes?  Manufacturers might think of machined plastic as an option when their final production quantities will be too small to justify the cost of a mold or when they are creating a highly-precise part that is too intricate for a mold. On the other hand, if they’re using a mold for the final product, they might assume they need to use a mold for the prototype, too.

But that is not always the case. While not all prototypes lend themselves to molds, most prototypes can be made with machined plastic parts depending on the design. Some molded designs have to become machining “friendly,” however it is relatively easy to do with the right plastic machining vendor.

Here are some of the advantages machined plastic prototypes can offer:

Flexibility. Whatever a designer creates for a mold can be created just as effectively with a machined part. The difference comes when it’s time to make adjustments. For molding, that means making a whole new mold at a cost that can run upwards of tens of thousands of dollars. Compare that to machined plastic parts, where manufacturers can make adjustments for next to no cost.

Shortened Time Frames. Machined plastic parts offer a much quicker turnaround when changes are made to a design. A new mold typically takes six to ten weeks to make. For a machined plastic part, a new prototype can go into production soon after a designer communicates the changes needed.

Initial Production Costs. The machined prototype can save manufacturers money when it comes time for production, too. Instead of starting off with a mold, a company can use machined plastic parts for its initial runs. Once the company steps up production to the point where a mold becomes cost effective, the company can then shift to a mold. This will not only help cut initial production costs, but can also make it easier to make adjustments if any problems in the design are noted when the product reaches its first customers.

Peace of Mind. Besides the cost and time savings, machined plastic parts can also give designers some extra peace of mind. With molded parts, designers have to be fully committed to a design before going forward with the expense of creating a mold. The lower cost of producing machined plastic parts can give them more wiggle room. They can try out an idea without the fear of incurring huge costs if it does not work out. With all that flexibility, manufactures might just end up with a product that is not only cheaper to develop, but better designed as well.

But what about the new frontier—3D printing? As with machined plastic parts, making changes to a prototype can be quick and cost-effective. The difference lies in how closely those parts fit a manufacturer’s final needs. While 3D printed parts can work well for concepts and fit, they fall short when trying to use them to measure true performance and function. There are a number of reasons for this. First of all, 3D printing materials are still somewhat limited, so manufacturers don’t have the breadth of choices they would have with plastic machined parts. Second, tolerances are not as accurate as they are with machined parts. And finally, surface finishes are not as fine.

In the end, while 3D printing offers some initial cost savings over molds, it can come at the sacrifice of precision. Tweet This  For now, machined plastic parts can still offer the highest quality prototypes for the price.

Photo Credit: sussialfredsson, Twenty20