Heartland Enterprises supports OEMs with highly precise, large dimension CNC milling services using the latest vertical and horizontal machining centers available. We perform milling, drilling, boring, contouring, counter-boring, countersinking, forging and casting. Our company is well known for large dimension CNC milling, especially for the machining of large-sized pistons used by multiple industries. We’re a turnkey provider for our customers, managing all raw material purchasing, manufacturing, subcontracting, and delivery.

Highlights of our CNC milling services include:

  • Ability to accommodate parts up to 60″ x 30″ x 29″
  • Specialty, low, and high volume production runs for parts weighing up to 1,000 lbs
  • State-of-the-art machining centers that can achieve tolerances as tight as +.001″

Certifications & Quality

We’re AS9100D / ISO9001:2015 certified, practicing stringent quality control procedures to ensure that each part exceeds our customer’s expectations. We’re proud to serve the aerospace, oil & gas, agriculture, military, manufacturing, power generation, and semiconductor industries.

All parts are subjected to a rigorous inspection process using a highly accurate probe measurement system. We offer a wide range of in-house fixturing to accommodate an array of parts, supported by quick-change pallet systems that provide accurate and repeatable setups.

Material Capabilities


Featuring next-generation computer-controlled systems; all of our machining centers are operated in a cell to maximize productivity.

Our Okuma MA-600 4-axis horizontal machining center features a 39.37″ x 35.43″ x 39.37″ build envelope; and quick loading and unloading of parts using two 24.8″ x 24.8″ pallets.  To ensure maximum productivity, we’ve equipped the unit with auto gauging, tool breakage detection, high-pressure coolant, and tool management software. For vertical machining, our 4-axis Mori Seiki MV-65B, Mori Seiki NV7000, and Okuma Crown 4018 units utilize rotary tables and feature an 8,000 rpm spindle speed.  Our Mori Seiki units can accommodate parts up to 60″ x 30″ x 29″ and our Okuma unit offers a 40″ x 18.1″ x 17.7″ build envelope.

Case Study:

Implementing multi-function equipment to reduce part-handling
Job Description

A repeat client requested a significant increase in quantity of an existing large, 75 lb. cast iron piston.


Historically over 5 different machines across 17 unique operations were needed to fully complete this part, resulting in long production runs and costly parts.


Heartland partnered with our Okuma distributor to analyze our process and equipment. To be more productive and cost effective, we implemented a Multus U-4000 multi-function CNC machine, which includes a main and sub spindle as well as a flexible milling head. The new equipment allowed us to reduce the number of operations to complete the increased orders of the large pistons from 17 to 6 operations, saving time and reducing part handling from machine operators continuously moving the large parts.

Contact Us


Machining Process Milling
Equipment Okuma MA-600
Mori Seiki MV-65B
Mori Seiki NV7000
Okuma Crown 4018
Machinery Axis Multi-Axis
Fixturing In-House Fixturing and Tooling Pallets
Tolerance (±) 0.001 in
Maximum Weight up to 1000 lb
Materials Aluminum
Alloy Steel
Carbon Steel
Cast Iron
Inconel 718
Inconel 901
Inconel 625
Stainless Steel
Quality/Inspection Probing
Production Volume Minimum 5
Specialty Production Shop
High Volume
Available Lead Times1 4 w
1 Quoted on job by job basis

Additional Information

Industry Focus Aerospace
Gas and Oil
Power Generation
Industry Standards International Organization for Standardization (ISO) 9001:2015 / AS9100D
File Formats Adobe Illustrator (AI)
Drawing Interchange Format, or Drawing Exchange Format (DXF)
Initial Graphics Exchange Specification (IGES), ANSI file format.
Inventor (IDW, IPT)
Joint Photographic Experts Group (JPG or JEPG)
Product Data Exchange using STEP (PDES), Standard for the Exchange of Product Model Data. A standard format for exchanging data between advanced CAD and CAM programs.
Portable Document Format (PDF)
Pro-E or Pro/Engineer (DRW, PRT, XPR)
Standard ACIS Text (SAT)
3D ACIS Model File
SolidEdge (DFT)
Standard for the Exchange of Product Model Data (STEP)
Tagged Image File Format (TIFF)
Unigraphics (PRT)