Case Studies News

Case Study: Strand Design

HPI Case Study


Customer: Strand Design; Chicago, Illinois
Part: Fourneau Bread Oven
Batch Size: Prototype to Tooling 
Material Cast: Gray Iron 

What it is: 

The Fourneau Oven is a cast-iron container that goes inside of an oven. It is designed to make bread using the no knead method made famous by Mark Bittman of The New York Times. The device's walls heat the dough evenly and the enclosed cooking space traps the steam from the baking bread, creating a golden, crispy crust.

Customer Challenge: 

Strand Design came to HPI many different times with multiple design molds for the oven that weren't possible due to the way it was designed. The designers asked HPI to reengineer the molds to add proper gating and risers to have it done within a short time span. Once the design was tested, it was noted that it was too heavy as one solid piece. 


As designers, Strand Design did not want to hand over the design work to a third party. So, Hoosier Pattern worked side by side with the owners to redesign the oven to make this project a reality. The final design was broken up into parts so the container was easier to handle. The 3D printed sand molds were printed within a really tight schedule and came out perfectly.



Ultimately, Strand Design opted to not only have Hoosier Pattern print the prototypes for the Fourneau Oven, but they decided to have Hoosier Pattern complete the tooling for it as well. Strand Design's Fourneau Oven is just one of the many projects that proves Hoosier Pattern is the one stop shop for prototyping projects that will ultimately need tooling in a short amount of time. 

HPI Competitive Advantage: 

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


It was a very exciting mail day when we recieved our own Fourneau Ovens. Congratulations, Strand Design on this awesome product you have made. Hoosier Pattern is excited and proud to be apart of it. Happy Baking! 


To order your own Fourneau Oven click here.

Case Study: OK Foundry & Oswalds Mill Audio

HPI Case Study

Client: OK Foundry, Richmond VA 
End User: Oswalds Mill Audio
Product: Cast Iron Open Baffle Loudspeaker


OK Foundry, an iron foundry based in Richmond VA well known for their architectural castings, was recently involved in creating a very unusual end product: a large, freestanding open baffle speakers made of gray iron. The dimensions for this one-of-a-kind set of speakers were 34.6" x 51.1" x 3" each and weigh around 330 pounds each.  

OK Foundry’s client, Oswalds Mill Audio (ΩMA), is a unique audio company based in DUMBO, Brooklyn. Their design philosophy states, “Instead of following current trends and embracing so called ‘cutting edge technology’ we take a look back.” All of their hand made audio equipment is made in Pennsylvania out of local hardwoods, slate and steel. In addition to their extremely high-end products having a retro appearance to them, they also embrace audio fidelity concepts used in cinemas and studios in the 1930's through the 1950's.

ΩMA had created a design for a large open baffle loudspeaker system cast from iron. Because of the complexity of the design, the foundry determined that the 3D sand mold made more sense than the price for tooling for essentially a “one-off” casting. Also, the tooling to extract the mold would have compromised the design and because HPI was able to print the right and left sand molds there was no need to individually tool the same set.


HPI created the complex mold utilizing our ExOne® 3D Sand Printer and OK Foundry was able to pour and create a remarkable product which will be on display at the International Contemporary Furniture Fair, May 17th-20th at New York City’s Jacob Javits Convention Center.

Photographer Cynthia van Elk has provided some photos capturing the whole process of creating the speaker from sand mold to end product.

HPI takes pride in being able to provide a wide range of solutions to complex design issues facing foundries and fabricators today.