Case Studies News

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

Case Study: Strand Design

Product Development and Prototypes On A Time Constraint

Chicago designers get help with redesign, a prototype, and tooling for a project all in one place.

Client: Strand Design

Product: Fourneau Bread Oven

Batch Size: Prototype

Material Cast: Gray Iron

Traditional Method Timeframe: 2-3 Weeks

HPI's 3D Sand Printing Method Timeframe: 1 week

Product Overview

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 crispy golden crust.

Client Challenges

Strand Design came to HPI more than once with multiple oven design molds that weren't possible due to the way it was designed. The designers asked HPI to re-engineer the molds to add proper gating and risers, allowing it to be completed within a short time span. Once the design was tested, it was noted that it was too heavy as one solid piece.

Our Solution

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

Results & Conclusion

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

Our Competitive Advantage

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

"Working with Hoosier was such a pleasure and they were so accommodating that we already knew before the prototypes were done that we would want to work with them to create the production tooling for the project" - Ted Burdett, Co-Owner, Strand Design

If you’d like to see the Fourneau Oven and learn more about how it works, click here

 

When To Use 3D Printed Sand

In the metal casting industry, two basic pieces are needed: a mold of some sort and a foundry to pour the mold. A traditional pattern shop supplies the pattern while a foundry packs sand around the pattern to make the mold. From there, The mold is poured resulting a casted part.

Hoosier Pattern fits the bill of the traditional pattern shop, but our expanded capabilities give us a competitive edge with the addition of our in-house 3D sand printer. By printing ready-to-pour-sand molds, we are able to bypass the tooling, possibly saving our customers time and money.

Since purchasing a 3D sand printer and having it in our facility since 2013, HPI has made strides within new and diverse industries. The possibilities with sand printing are almost endless and with the HPI team, we try to make every "out of the box" concept a reality.

We are always looking for new customers and ways to solve problems within the industry. When talking with new and potential customers we are often asked questions like the following:
 

                "How do we know when we should use 3D printed sand for our projects instead of using traditional foundry tooling?"

                "What are the advantages of sand printed parts?"

                "How would using 3D sand printing benefit my project?"


Since 3D sand printing is still a fairly new process in the industry, it's important to give our clients a detailed overview of what to expect when starting a new project with this process. If we had to sum up the benefits of 3D sand printing in a few points, we'd be sure to hit on the following:

Perfect for Prototypes

Sand printed molds and cores are printed from a CAD file and are a one-time use. This process makes printed sand molds and cores ideal for prototyping parts. CAD files can be altered in a very timely manner, allowing for quick changes to the design if needed. Customers are able to avoid paying for tooling that is produced and priced to be used hundreds or thousands of times.

 

Multi-Piece Core Assembly With A Single Printed Core

Eliminate multi piece core assemblies by printing a single “merged” core to eliminate mud joints and improve accuracy of core.

 

Easy to Manufacture

In the world of pattern-making and design, it's not uncommon for engineering changes to pop up. In traditional pattern-making, these changes no matter how small, can pose a problem once the tooling has been produced. Since our 3D sand printed molds and cores are printed from a CAD file, the customer is able to create and design geometrically complex castings to be manufactured with ease. Designs don't have to be compromised in order to meet low-cost, high-functioning manufacturability.

 

It's Fast

The conventional method of building a pattern can take anywhere from weeks to months. HPI's standard lead time for 3D printed sand is 2 weeks, with the option of 1 week and 3 day expediting available. This turnaround time includes printing, cleaning and packaging the parts, followed up by sending the item to a foundry to be poured.

 

The printer at HPI has a job box the size of 70" x 39" x 27" and prints about 1.3" every hour. A full job box takes anywhere from 19-23 hours to print, making for an incredibly quick turnaround.

 

Hoosier Pattern is rooted in traditional pattern-making and will continue to produce high-quality traditional foundry tooling. However, the 3D sand printer opens opportunities to work with clients who need smaller quantities and quicker turnarounds. It is a tool in the HPI toolbox used to help customers with projects and set us apart from the competition. In fact, Hoosier Patternis the only place in the United States that owns and operates equipment in house and supplies high-volume production tooling.

 

Our in-house printers and dedicated team members work diligently and consistently to bring the best products to our customers. We will continue to raise the bar within the industry and always work to improve our company and our products, because our customers deserve the best. 

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. 

Solution: 

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.

300

Conclusion: 

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


Background

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.

Solution

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.