Machine Ways

Detroit Edge Tool Company is the largest manufacturer of machine ways and rails in the world!

DETCO’s machine way manufacturing facilities have the latest in CNC machining centers and grinders, which allows DETCO the ability to produce tight tolerance machine ways, bed ways, lathe ways, and rails demanded by machine tool builders. DETCO’s robot automation rails, gantry rails, and guideways have become industry standard for dynamic motion in automation environments. Hardened ways and rails determine the basic accuracy of machine tools, assembly machines, and automation equipment. Flame hardened, or through hardened, DETCO’s machine ways and rails are manufactured to OEM specifications. The chart below illustrates these tolerances.

Machine Ways and Machine Rails
Detroit Edge Machine Ways are surface ground and hardened to customer’s specifications

What are Machine Ways?

Few machine tool components are more fundamental than the way system, which provides the interface between moving and stationary elements of the machine. Machine Ways can either be flame hardened or through hardened to 58-62 RC, and determine the basic accuracy of machine tools. Ways are robust in their build, and perform better in abrasive cutting applications or machines with high-powered spindles in corrosive environments.  Machine ways are the smooth, precise tracks that Machine carriages move on, such as robots, machine columns, and spindle housings. Special attention is given at the butt joints to see that the rollers and the runner blocks transition smoothly. These metal bearing plates are manufactured to such high precision that they can carry continual increases in load as their curvature becomes more convex. Special attention is given to see that the rollers and the runner blocks transition smoothly. Box ways are also called the linear motion bearings, and support the spindle and table and guide their movement.

Machine ways were used as far back as the 19th century. In the past machine builders used wooden ways, but the material of choice for machine ways became cast iron. Cast iron was a better material because it cooled into shape, fit with scraping and was easy to cut using single point tooling. Today we use cast iron, hardened steel, and other ferrous metals.

Types of Machine Ways

Plain sliding/ Slide ways

This is a machine way with sliding friction. They can be an integral part of the bed or they can be attached on top of the bed and the slide mounted on the side way.


• Easily check geometric feature
• Large bearings are provided for the slides
• Adjust clearance (a gab strip may be required)

Rolling element

Moving elements are supported on the flat, and the straight guide ways are mounted on the static elements. Rolling element machine ways have low friction which means when moving along the guide’s direction their resistance is low.


• Lower stiffness
• less damping
• require no power to support load


This is a combination of a hydro-static bearing with a flat, straight way. A restriction is formed between the guide and the pressurized oil pocket. The pressure in the pocket is controlled by the oil flow thus the pressurized oil flow supports the load.


• They have little friction
• Require a pocket

Different Industries Use Different Machine Ways

Detroit Edge Machine Ways are used on all Boeing Wing Spar & Skin Profile Milling Machines in North America

Every industry has its own machines that are reliant on machine way or rail guides. Here are a few different industries that use different guide systems:

Ball rail systems

Ball rails are used in applications in the industrial robot industry. This is a fixed rail track with circulating ball bearings and runner slides. It is suitable for industrial environments because of its load resistance.

Roller rail systems

These are suitable for use in machines like injection molding, robots, printing, and paper machinery, presses, and heavy-duty machinery. Roller runners slide in a fixed rail system. Freedom of movement can be adjusted with the central roller during assembly.

Miniature ball rail systems

Miniature ball rail systems are mostly used in medical technology and in the semiconductor industry. These guide rails require extremely small ball-bearings, that have a very high load capacity. These guide rail units usually have the same load ratings for four different load capacities.

Cam roller guides

The conveyor and automation sectors make use of these guides for the undercarriage of their machinery. They are specially designed for speeds as high as 10m/sec.

How to Choose a Machine Way System?

Box guides

Extremely heavy loads are better supported by box way systems. A machine is made with slower spindle speed, extremely tough or abrasive material, and requires proportionally lower feeds. In short, they are a better choice for heavy-duty applications where rapid movements are critical. These guide rails absorb shock loads better.

Material Composites

Machine guides are usually made from hardened high strength galvanized steel and are corrosion resistant. A hardened rolling surface is paramount for bearing components for long life use.

Machine Way Materials

    • Steel

      This is the most popular metal for most types of manufacturing. This metal is prized for its durability and its strength, but it is unfortunately prone to erosion. Like stainless steel it is graded for specific purposes and used in manufacturing and automotive industry.

    • Ferrous Metals

      They contain steel and a variety of alloys or cast iron. If strength is what you want in machine building this is the product you are looking for.

    • Cast Iron

      This is the metal mostly used in machinery and the automotive industry. It surpasses aluminum in its popularity and strength. Various kinds of tooling are manufactured from this product. It is preferred to steel for machine tooling because of its vibration and dampening qualities.

Methods Used for Hardening These Surfaces

Flame Hardening

This heat treatment process is where oxyfuel gas is directly impressed on the surface area to be hardened which is then subjected to quenching.  Detroit Edge uses a water, oil, or air quench process depending on the application.  The result is a hardened surface layer on the outside over a soft inside layer. This application’s costs are considerably less than induction hardening.

Learn more about Detroit Edge Flame Hardening.

Through Hardening

Steel that is hardened needs to contain a certain amount of carbon in its iron mix. Carbon dissolves in molten iron and is therefore added to the iron mix. This will cause the components that are treated to harden all the way through to the core.

Detroit Edge Box Ways used in a 480” Column Travel Phoenix Gantry Mill

Standard Specifications - Machine Way Tolerances

Closer Tolerances are available upon requestFinishedSemi-finished
Dimensional+/- .001+/- .025+/- .003+/- .075
Matched Thickness or Width.0005.013.0015.04
Match at Butt Ends.00025.006.001.025
Twist.001 T.I.R..025.002 T.I.R..05
Squareness.0003.0075.0015 T.I.R..04
Parallelism.0002 T.I.R..005.0015 T.I.R..04
Hole Location.0005.013.001.025
Micro Finish8/160.2/0.4320.8