Lawton St. Paul (formerly Northern Iron & Machine) is an iron foundry in St. Paul, Minnesota. We deliver precision-engineered castings for transportation, energy, and infrastructure. Backed by modern foundry techniques, strong engineering support, and ISO-certified quality systems, Lawton St. Paul provides reliable, high-performance components tailored to your specifications.
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Lawton Standard St. Paul produces the highest-quality machined cast iron parts in our three induction-melting furnaces.
We can produce castings of gray, ductile, and austempered ductile iron from a few pounds up to 250 lbs. We can produce in both high-volume and short-run quantities.
Many of our iron parts are routed to our machining facility, where our CNC equipment transforms the castings into precision parts.
Whatever your iron casting needs, Lawton Standard St. Paul can assemble them to your specifications. We have the knowledge and equipment to manufacture simple inserts and multiple-component assemblies.
Lawton Standard St. Paul supports manufacturers and OEMs across a range of heavy-duty industrial markets that demand reliable, repeatable castings and finished components. We serve customers who need iron parts that perform under stress, hold precision tolerances, and reduce supply chain complexity by combining casting, machining, and value-added services in one place.
Precision cast housings, brackets, and structural components
Machined and subassembled parts ready for installation
Wear-resistant and load-bearing components for mobile and stationary equipment
Close-tolerance assemblies for drivetrain, steering, and suspension systems
If your product requires engineered iron castings, CNC-machined components, or assemblies delivered ready to install, St. Paul is designed to be the supplier that shortens your supply chain and keeps quality consistent across runs.
Cores create the internal geometry of an iron casting, while the mold forms the outer shape. At Lawton Standard St. Paul, cores are produced using two proven processes: phenolic urethane and shell core.
Phenolic urethane cores are made on an IMF Disco 3500 and Simpson ABC 6 system. In this process, silica sand is blended with a three-part binder and blown into a precision core box die using compressed air, forming the negative shape required for the casting.
Shell cores are produced on Redford shell core machines. Here, sand is mixed with a heat-activated resin and blown into a heated core box. The heat cures the resin, forming a rigid core with excellent dimensional stability.
After forming, cores may be coated with core wash and cured in a forced-air oven. This step improves surface finish and helps prevent iron penetration during pouring. Once complete, cores are placed into the mold before the cope and drag mold halves are closed, preparing the assembly for casting.
Lawton Standard St. Paul produces gray and ductile iron castings using two high-capacity automated green sand molding lines designed for repeatability, efficiency, and consistent casting quality. Green sand is a controlled mixture of silica sand, Bentonite clay, and moisture, carefully monitored to maintain the strength, permeability, and compaction required for reliable molds.
In this process, sand is compacted around a precision pattern that forms the negative of the casting’s shape. The pattern also includes the runner, gate, and riser system that controls how molten iron flows into the mold. Each mold is produced in two halves—the cope (top) and drag (bottom)—which are assembled after the cores, filters, and risers are positioned. Once closed, the mold is weighted to ensure the halves remain sealed during pouring.
St. Paul molding capabilities include:
Osborne molding line
Mold size: 30 × 30 × 12 inches
Flask-based system for larger and more complex castings
DISA vertical molding system
Mold size: 20 × 24 × 8 inches
Match-plate tooling for efficient, high-volume production
These complementary molding systems allow St. Paul to support a wide range of casting sizes, geometries, and production volumes, helping customers move from prototype to repeat production with consistent results.
At Lawton Standard St. Paul, iron is melted in three 5-ton coreless induction furnaces, producing up to 45 tons per shift. Furnaces operate at approximately 2,750–2,800°F, melting a controlled charge of scrap steel and internal iron returns.
A General Kinematics charge feeder and Gaylord preheat hood support efficient furnace charging and consistent melt conditions. During the melt cycle, alloying elements are added to maintain the required chemistry for each iron grade.
Once the target composition is reached, the furnace is tapped, and molten iron flows into a tundish or transfer ladle, where slag and impurities are removed. From there, iron is transferred to pouring ladles and carefully poured into prepared molds.
St. Paul produces both gray iron and ductile iron, supporting applications that require a balance of strength, machinability, and durability.
After solidification, castings move through shakeout, where sand is separated from the part and reclaimed for reuse. The gating and riser system (sprue) is removed and recycled into future melts. Castings are then shot blasted and ground to remove remaining sand, parting lines, and excess material, producing a clean as-cast surface ready for machining or shipment.
For customers requiring finished components, Lawton Standard St. Paul provides extensive in-house CNC machining, specializing in gray and ductile iron castings in the 50–250 lb range. Our machining department includes Mori Seiki horizontal and vertical machining centers and Okuma turning centers, supported by additional tooling, finishing equipment, and precision inspection systems such as Brown & Sharpe automated CMMs.
By combining casting, finishing, machining, and inspection in one facility, St. Paul helps customers reduce the number of suppliers, shorten lead times, and receive ready-to-install iron components built to specification.
At Lawton Standard St. Paul, metallurgy plays a central role in delivering consistent gray and ductile iron castings. Our in-house metallurgical lab supports every stage of production—from melt chemistry to final verification—helping ensure castings meet customer specifications and perform as expected in the field.
Key metallurgical capabilities include:
Tensile testing to verify the strength, yield, and elongation properties of cast iron
Optical emission spectrometry for fast, precise elemental analysis of molten iron
Nodularity testing using ASTM reference standards to confirm ductile iron structure
Green sand testing to control mold sand chemistry, strength, and permeability
Heat treating using ovens certified to AMS 2750E for annealing and stress relief
These systems allow the St. Paul team to monitor materials, molds, and finished castings with precision—ensuring the mechanical properties, microstructure, and dimensional integrity required for demanding industrial applications.
By combining metallurgical expertise, process control, and modern testing equipment, Lawton Standard St. Paul helps customers achieve reliable castings, consistent machinability, and repeatable production results.
At Lawton Standard St. Paul, quality is built into every stage of production, from incoming materials to finished parts. The facility operates under a comprehensive quality management system, including ISO certification, with documented controls covering purchasing, production, inspection, and shipment.
Quality verification includes metallurgical testing, hardness checks, dimensional inspection, and process monitoring. During initial production runs, castings undergo full dimensional layouts and soundness evaluation, while ongoing production is monitored to detect tooling wear and maintain consistency.
Inspection equipment includes coordinate measuring systems and manual gauging tools, allowing the team to verify critical dimensions and maintain stable processes throughout machining and finishing.
This disciplined approach helps ensure that every casting leaving St. Paul meets customer specifications for chemistry, structure, and dimensional accuracy, delivering reliable parts ready for production use.
The St. Paul foundry has been producing iron castings for industrial customers since 1892, when the operation began as a malleable iron foundry serving growing Midwestern manufacturers. Over more than a century, the facility has continuously adapted. We’ve invested in new equipment, expanded machining capabilities, and refined our processes to meet the needs of OEM and industrial customers.
Today, Lawton Standard St. Paul combines that long-standing foundry and machining experience with modern production systems and the shared resources of The Lawton Standard Co. This allows the team to support customers with the responsiveness of a local operation while benefiting from the engineering standards, investment, and collaboration of a broader manufacturing network.
What sets St. Paul apart is its focus on doing the fundamentals exceptionally well: controlled processes, skilled people, and the ability to turn complex castings into finished components ready for production use. Customers rely on the team not just for iron castings, but for consistent quality, dependable delivery, and the kind of practical problem-solving that comes from generations of foundry experience.
Committed to clean air and community transparency
Lawton Standard St. Paul is looking for great people to join our team. We offer excellent benefits, healthcare, a 401 (k), and 15 paid days off in the first year.