AC Motors designed for Hazardous Duty, Critical Duty, and Specialty Applications

About Mil Spec, Inc. Totally Custom Orientated

About Mil Spec, Inc.

Mil Spec, Inc. is a designer and manufacturer of electric motors engineered to meet the specific requirements of unique applications.

Mil Spec, Inc. was founded in 1986 with the ambitious goal of obtaining U.S. Navy certification of our vacuum pressure impregnation (VPI) sealed insulation system. In 1988 we received certification by passing a most rigorous group of tests and documentation retention procedures, and joined eight other qualified manufacturers holding that certification. Today, we are one of only four electric motor manufacturers retaining the Navy approval.

In addition to providing motors for the Navy, we also design and manufacture electric motors for the U.S. Army and highly custom industrial motors.

We are extremely flexible in our approach to your requests. We have no rigid policies regarding development costs, stocking programs, warranties or terms of sale. We are a totally custom oriented company built on favorable pricing, short and reliable lead-times, quality products, clear information and comfortable relationships.

VPI Vacuum Pressure Impregnation Sealed Insulation System

This system was developed for harsh environments to greatly extend the winding life expectancy and therefore the motor life expectancy. Each stator coil is hand wrapped with a fibrous wicking material and inserted into the lamination slots. After all coil connections are made and protected, the stator is loaded into a pressure vessel and immersed in the specially selected epoxy resin. All gas, including that held by surface tension, is evacuated under vacuum. The epoxy is drawn into the stator core, completely occupying all voids in the winding. After a series of processes, ending in a controlled bake, the winding is 100% impregnated and sealed. Each stator then receives a 24-hour submergence test under water that has been treated to maintain stringent surface tension values. All electrical test results collected before and after submergence are serialized and maintained at the factory for a minimum of seven years.


Electric motors provided for U.S. Army hardware must have two extraordinary characteristics. They must be highly reliable and uncompromisingly versatile. Each motor must function, whether operating life support equipment or combat weapons in harsh environments such as the desert, the mountains, the arctic, or the tropics. Each must be capable of withstanding extreme temperature variations and exposure to sand storms, monsoons, ice storms and salt laden fog.

Mil Spec, Inc. is a supplier of electric motors meeting these rigorous performance and environmental requirements. Mil Spec, Inc. will provide motors meeting:

  • NEMA MG1 standards for extreme temperatures (-50 ° to +160°F)
  • MIL-STD-810 method 507 for humidity standards
  • MIL-STD-810 method 509 for salt fog standards

Previously developed electric motors for the U.S. Army include Series 13211E, 13214E, 13221E, 13225E and 13229E.

These motors are furnished with permanently lubricated bearings conforming to AFBMA-STD-20 ABEC 1 with C3 internal clearance for superior performance during an extended life cycle. Also supplied are corrosion resistant shafts, passivated to meet QQ-P-35 standards, corrosion resistant fasteners and a unique protective rotor coating.

We currently have NSN’s in place to ease the process of gaining our products.


Mil Spec, Inc. is an eager and dependable manufacturer of specially designed electric motors that satisfy your custom requirements. Those needs might include an extended design life, special dimensions or accessories, unusual materials or coatings, quiet operation, super precision balancing, special shaft extensions, special bearings or all of the above. With our certified vacuum pressure impregnation system, we have all the resources for complete corrosion protection.

We are a small flexible company that is not limited to existing designs or existing standards. We will work with you to best meet your needs rather than merely offering something close.

Each design is a special combination of electrical, mechanical and metallurgical considerations with a watchful eye on budget and schedule.

All of our industrial motors are hand wound with epoxy-coated stators and rotors. All inquiries are individually handled by experienced factory personnel. All electric motors are built to our detailed drawings which will be submitted for your approval. We test all motors prior to shipment. Depending on your concerns, we offer a standard package of tests or will offer a tailor-made package.

Mil Spec, Inc. offers competitive prices, dependable lead times, quality products and responsive information.


Electric Motor Design Enclosures

  • Open
  • Open Drip-proof (ODP)
  • Totally Enclosed Fan Cooled (TEFC)
  • Totally Enclosed Non-Ventilated (TENV)
  • Totally Enclosed Air Over (TEAO)
  • Explosion-proof (EXP)

NEMA Frames and HP

  • NEMA 42 thru326
  • 1/8 HP to 30 HP

Electrical Design

  • Standard and special voltages up to 600 VAC
  • Three phase and single phase
  • Single and muti-speed
  • 25HZ, 50HZ, 60HZ, 200 and 400HZ
  • Speeds from 2 pole to 12 pole
  • Class B, F and H insulation

Standard Design Features

  • NEMA Design B
  • Painted Internal Surfaces
  • Single voltage
  • 60 Hertz
  • Class F Insulation
  • Continuous Duty
  • 50°C Ambient
  • Bearings: Permanently Lubricated
  • Lifting Provision: Eye Bolt 180T and Larger
  • Stainless steel shaft
  • Each motor is serialized
  • Hand wound
  • Balance: .001

Optional Design Features

  • VPI Sealed Insulation System
  • IP 55-58 Degree of Protection
  • Dual voltage
  • Locked bearing construction
  • 40°, 65°, 80° C Ambient
  • Intermittent Duty
  • Monel Shafts
  • Thermal protection
  • Precision or super precision balancing

Optional Service Conditions

  • Exposure to salt spray
  • Exposure to salt splashing
  • Salt laden atmosphere
  • Submergence
  • Temperature from -50°F to 176°F

Routine Tests

  • No load watts input, amps, and RPM
  • Winding resistance
  • High potential test
  • Insulation resistance
  • Mechanical balance
  • Visual inspection

Periodic Tests

  • Full performance to 125% rated load
  • Locked torque and current
  • Breakdown torque
  • Temperature rise

Contact Us


1(636) 349-2205


1(636) 343-1934

Garry Hodges

Director of Business Development

Steve Hauck

Director of Engineering

Rich Lohmann

Mechanical Engineer

Jared Campbell

Quality Manager

David Rhoads

Senior Design Engineer

Jeff Ferris

Senior Electrical Engineer

Arledi Jones

Government Sales Manager

Lauren Guenther

Senior Accountant

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