What Waupaca Foundry makes

Waupaca Foundry is an iron foundry. It pours gray iron, ductile iron, high-strength ductile iron, and austempered ductile iron (ADI) castings, and the company describes itself as the world's largest manufacturer of these four casting types and the largest non-captive iron foundry in the world. Its plants melt nearly two million metric tons of iron each year and produce castings weighing as little as 2 pounds and as much as 350 pounds.

The work runs from raw material to finished component. Waupaca designs, builds, and maintains its own vertical molding machines, and it runs in-house core making, trim presses, and automated grinding. Metallurgists validate castings with casting-simulation and solidification-modeling software before the iron is poured, and the company machines castings in-house as well, including a machining operation adjacent to its Plant 2/3 gray iron foundry that CNC-machines brake components for the commercial vehicle market. Waupaca collaborates with OEMs and their Tier 1 suppliers on lightweighting, on converting fabrications and weldments to iron castings, and on VA/VE cost work. It has also moved into additive methods: a company engineer co-authored the first definitive study comparing conventional cores to 3-D sand-printed cores, work the American Foundry Society recognized in 2025.

The customer base is broad within heavy industry. Waupaca markets castings to automotive, off-highway, commercial vehicle, rail, industrial, oil and gas, and municipal customers, and its lightweighting programs reach electric-vehicle applications through control-arm and structural conversions.

Ownership and history

The foundry traces to 1871, when John Rosche started the Pioneer Foundry on the banks of the Waupaca River. The modern company dates to 1955, when metallurgist Clifford Schwenn acquired it and renamed it Waupaca Foundry, Inc. Through the 1960s it grew from a 4-ton cupola operation into a multi-plant molder, installing the first automatic vertical molding line in the United States at its Plant 1 in 1967. By 1999 it described itself as the largest non-captive iron foundry in the world, with more than 2,300 employees.

Ownership has passed through several hands. The Budd Company acquired Waupaca in 1968; Thyssen bought Budd in 1978; the company operated as ThyssenKrupp Waupaca from 2002 and crossed $1 billion in annual revenue in 2005 under that name. In 2012 KPS Capital Partners acquired the business and restored the Waupaca Foundry, Inc. name. Proterial, Ltd., then known as Hitachi Metals, bought it in 2014. On February 29, 2024, Waupaca Foundry was sold to Monomoy Capital Partners, its current private-equity owner. Daniel Collin serves as Chairman.

Today the company runs its headquarters and three foundries and a machining plant in Waupaca, Wisconsin, plus foundry operations in Marinette, Wisconsin (Plant 4) and Tell City, Indiana (Plant 5), with more than 4,000 employees across the group. The leadership team is led by Chief Executive Officer Mike Hawthorne, appointed in February 2025 after roles running Bendix Commercial Vehicle Systems and New York Air Brake; he succeeded Mike Nikolai, who had led the company for nine years. Rob Johnson is Executive Vice President of Administration, CFO, and Treasurer; Steve Wasil is Chief Commercial Officer; Mary Blair is Chief Supply Chain Officer; Todd Pagel is Vice President of Operations; and Jarrod Osborn is Vice President of Engineering.

Certifications and quality

Waupaca Foundry states that it maintains a quality management system registered to ISO 9001:2015 and IATF 16949:2016 at all foundry locations, with certificates available per plant for Plant 1, Plants 2/3, Plant 4, and Plant 5. IATF 16949 is the automotive-sector quality standard, and holding it across multiple foundry sites is the baseline expectation for supplying vehicle programs. The company builds quality control into the process rather than treating it as a final gate: it cites 5S, Kaizen, Green Belt, and Six Sigma practices, casting simulation before pour, in-line machine monitoring, and end-process verification. That discipline shows up in customer recognition. Waupaca earned General Motors' Supplier Quality Excellence Award in both 2024 and 2025.

Known customers

Waupaca Foundry does not publish a customer roster, which is normal for a merchant iron foundry supplying OEM and Tier 1 programs under confidentiality. One relationship is on the public record through a quality award:

Beyond that, the company's own materials describe collaboration with automotive OEMs and their Tier 1 suppliers, plus off-highway, commercial vehicle, rail, industrial, and oil and gas manufacturers. Those are sector statements, not named accounts.

Investment and stability

Waupaca Foundry has been reinvesting through its most recent ownership change rather than pulling back. In October 2025 it announced the final stage of a multi-year capital program worth more than $100 million to modernize operations, improve worker safety, and add advanced foundry technology, with roughly $20 million of that directed at its Plant 4 foundry in Marinette, Wisconsin. The program is a concrete signal of continued investment in domestic iron casting capacity. In the same period the company announced an expansion of its sales organization. It also adjusted its footprint, with the closure of a finishing plant in Ironwood, Michigan reported in January 2025.

Sourcing evidence

Waupaca's US ocean-import record is thin, which is what you would expect from a domestic iron foundry that buys scrap, alloys, and services close to its plants. US customs bill-of-lading records show 491 sea shipments between February 2015 and December 2025, at an average of about 0.26 TEU per month. The record is not a picture of a company importing production inputs. It is dominated by intercompany flow from Hitachi Metals, the former parent group, and by anti-vibration rubber components and auto bushings from suppliers such as Shanghai Automobile Import and Export and Sumiriko AVS Wuxi, with the most recent shipments being capital equipment: machining centers, ABB robotics, and Linde forklifts. Because the import record reflects related-party and equipment purchases rather than demand for production materials, it is not a useful read on the foundry's order book, and this profile does not treat it as one.

Coverage caveats: these are US ocean-freight records only. Domestic scrap and alloy purchases, truck and rail movements, and any air freight do not appear; some records name freight intermediaries rather than manufacturers; and product categories come from declared manifest codes, which are noisy. Absence of a record is not evidence of absence.

Frequently asked questions

What does Waupaca Foundry make?

Waupaca Foundry manufactures gray iron, ductile iron, high-strength ductile iron, and austempered ductile iron castings. It melts nearly two million metric tons of iron a year and produces castings from 2 to 350 pounds for automotive, off-highway, commercial vehicle, rail, industrial, and oil and gas customers, and machines castings in-house.

Who owns Waupaca Foundry?

Waupaca Foundry has been owned by Monomoy Capital Partners, a private-equity firm, since February 29, 2024. Earlier owners included The Budd Company, ThyssenKrupp, KPS Capital Partners, and Proterial (formerly Hitachi Metals). The company was founded in its current form in 1955.

Where is Waupaca Foundry located?

Waupaca Foundry is headquartered at 1955 Brunner Dr, Waupaca, Wisconsin 54981. It operates three foundries and a machining plant in Waupaca, plus foundry operations in Marinette, Wisconsin and Tell City, Indiana.

How many employees does Waupaca Foundry have?

Waupaca Foundry reports more than 4,000 employees across five foundry and machining facilities. Company materials variously cite figures from 3,000 to 4,500 depending on the source and date.

What certifications does Waupaca Foundry hold?

Waupaca Foundry states that it is registered to ISO 9001:2015 and IATF 16949:2016 at all foundry locations, with certificates available for each plant. IATF 16949 is the automotive quality management standard required to supply vehicle programs.

Who are Waupaca Foundry's customers?

Waupaca Foundry does not publish a customer list. It has earned General Motors' Supplier Quality Excellence Award two years running, and it describes serving automotive OEMs and their Tier 1 suppliers along with off-highway, commercial vehicle, rail, industrial, and oil and gas manufacturers.

Last verified September 28, 2026. Is this your company? Request a correction.