Some people are unfamiliar with the term “investment cast sprue,” but it is a very important part of the precision casting process. A sprue is a hollow structure that allows multiple parts to be cast at one time. It connects two to several individual wax patterns, allowing a single pour of molten alloy to fill multiple patterns at one time. For small parts, this could mean that many castings could be made at once, making the process more efficient, time-saving and cost-effective. Properly constructing sprues takes expertise and experience from the foundry staff.