Tolerancing of diecastings is highly dependant on the shape, length and location of each feature as well as the alloy being used for the application.

The most important factors when tolerancing a component are not how tight any tolerance can be, or the process capability that can be achieved, but what is needed to meet functional requirements and which dimensions and features are critical. Once specified, the appropriate process will be chosen to best achieve them. There are cases when tolerancing is looser than is desirable, leading to poor product quality and life. Equally, there are cases when it is higher than is necessary, which leads to higher product cost and scrap rates. Tolerances should be as tight as necessary, not as tight as possible.

Dynacast standards exist as a guideline for designers. In all cases, both standard and critical tolerances are covered. Standard tolerances can be achieved in all cases, with good tool maintenance, while critical tolerances may be achieved on a limited number of features through discussion with Dynacast. Where critical tolerances are not quoted, consult Dynacast. The tolerances achievable will be assessed, taking into consideration the form of the part, the proximity of the feature within the tool and its relation to other features on the part. Tool life and wear must be taken into consideration with tolerancing as this will affect short-term versus long-term process capabilities.

For specific suggestions on your application, contact us for a detailed analysis.