Design to Cost

Once you have chosen to manufacture a product using the investment casting process, the next step is to design the product so that it can be produced at the lowest cost and with the optimum functionality. The unique properties of our casting process are used for this. In other words, to control the production costs, the product has to be designed for optimum manufacturability.

The engineers at CIREX understand better than anyone else how Design to Cost has to be applied to investment castings. Design to Cost is a method that combines cost modelling and quality to deliver the best product at the lowest possible cost. The methodology is applied in the design process of a casting product.

By applying the design-to-cost method, cycle times are reduced and the need to perform additional operations are minimised. Consider the prevention of finishing or surface treatments. These operations are both costly and time consuming. The design phase is the ideal time to prevent and minimise these costs. Below, we describe three ways how we can reduce product costs during the design process:

1. Strategic gating

In the investment casting process, the positioning of the ingate is a vital feature that engineers must consider in their design. Each casting requires one or more ingates. During the design of the product, the position and measurement of the ingate must be considered. Ideally, the ingate’s location is seamlessly integrated into the design so that it does not disrupt the product performance. The ingate location should be incorporated on geometry adjacent to the thickest part of the casting to minimise porosity. Preferably, it should be on a surface that doesn’t have stringent tolerance requirements for functionality. Avoid isolated heavy sections, if possible, as these may require additional gating, which negatively impacts cost.


Using other manufacturing processes, complicated design features like lettering, date codes, internal threads, splines, and other unusual shapes require costly secondary operations. Investment casting, on the other hand, can incorporate these features directly into the casting, no matter how complex. Although this may slightly increase the cost of tooling, you will not have to pay for additional secondary operations for each part. This ensures a considerable drop in piece part price. Incorporating these complicated designs and cosmetic features into your investment cast geometry will eliminate secondary operation costs down the line.


To reduce your total costs, the most important thing is to involve the supplier at an early stage of the product design. Only this way it is possible to avoid potentially expensive design details and redundant product weight and to look at integrating multiple functions in one casting at an early stage. 

It regularly happens that customers approach CIREX and request several parts that will be assembled into one final product. By applying the Design to Cost methodology, we can consolidate these parts in one single casting without any secondary assembly. By doing this, our engineers help you to optimize the component so that you gain maximum benefit from the capabilities of investment casting, while also securing a decrease in piece part price with the elimination of secondary assembly operations.

Together with the customer, we can optimise the product and design ‘near-net-shape’. This design technique allows us to maximize the benefits of investment castings. This achieves a significant reduction in weight with the same functionality. All this with one goal: cost reduction. 

Experience is the best teacher when it comes to optimizing your part for performance to avoid costly redesigns. At CIREX, our engineers have gained considerable experience over the years. They know how to engineer features that ensure dimensional stability, and which features put castings at risk of failing. By involving our design team at an early stage, we can incorporate features like ribs and cores to provide strength and optimal solidification without sacrificing performance.

Do you have any questions about Design to Cost, or are you curious about the possibilities for your product?

Please contact us.