Case Study: Dalton Foundry

Foundry Uses HPI's 3D Sand Printer To Make Deadline

Dalton Foundry of Warsaw, Indiana had a case to solve for a customer—and time was running out.

Client: Dalton Foundry

Product: Gear Case Housing

Batch Size: Prototype (20)

Product Size: 29" x 26" x 12"

Material Cast: Class 30 Gray Iron

Traditional Method Cost & Timeframe: 8 Weeks at $13,000.00

HPI's 3D Sand Printing Method Cost & Timeframe: 1 Week at $1,165.00

Product Overview

The problem part in question was a section of 443-pound gray iron gear case. The corners—or ribs—in several points were cracking during the casting process. The gear case cover housing is used in industrial air compressors found at work sites to generate air and power. This was a prototype casting that was scheduled to go into production but couldn't be moved forward in the process if the end result was cracked.

Client Challenges

Dalton attempted several different processes and gating-related modifications, but a crack kept appearing. Because of the location and nature of the crack, Dalton employees thought the cracking may be a result of stress during the solidification process. Repeated simulations were run referencing the original design, which led to the conclusion that the defects were related to the design itself. The stress in the casting was the result of the original design’s base being so large that it took much longer to solidify than the other areas of the casting.

Our Solution

A plan was put in place to cut the metal tooling again, but the redesign of the part took much longer than expected. Now time was becoming critical to the project. It was at this point that Dalton turned to Hoosier Pattern and opted to make the cores using our 3D sand printer. In this specific case, Dalton saw the 3D printer could print directly from the CAD file without the upfront tooling cost—this was groundbreaking, especially with a prototype piece that had a history of cracking. With our 3D sand printing capabilities, design changes could be made quickly and a new core could be printed and pour-ready within days.

Results & Conclusion

The first pour using the 3D printed sand core was a success—no defects or cracks were found on the prototype. Twenty additional castings were needed and all of them were poured flawlessly using the 3D printed cores. Not only were there zero defects, but all the prototypes were made in a few days rather an in the few weeks a traditional tooling method would have required.

Our Competitive Advantage

Hoosier Pattern works very closely with all of our customers, enabling our designers to make changes on the fly to keep projects moving forward and meet customers’ needs and deadlines. Hoosier Pattern's 3D sand printer operation is effective and more practical for quick turnaround times.

"Our customer was up against the wall needing parts. We were aware of 3D printing and that a printed core would be turned in less than a week. The success of the part required two leaps of technological faith: stress simulation and using printed cores. Both worked out great" - Rob Burita, Tooling Engineer, Dalton Foundry

Posted in: General