Meet the Machine

Used Okuma GENOS L400: Two Axes on Purpose

The Okuma GENOS L400 has the bigger number in its family and the simpler machine. There is no live tooling, no C-axis, no Y-axis and no sub-spindle. That is not a gap in the spec sheet. It is a 2-axis CNC Lathe built for one job: turning.

This is a practical look at the L400 for a used buyer: who it fits, what the spec sheet says, where used listings disagree with it and what to check before you buy.

What the GENOS L400 Is

The GENOS L400 is a 2-axis CNC Lathe from Okuma: X and Z, a turret and a tailstock. It sits in Okuma's GENOS L family next to the L300-M, which uses the same 10-inch chuck but adds live tooling. In this family, the milling machine takes the lower number and the turning-only machine takes the higher one. We decoded that naming in How to Read an Okuma GENOS L Model Name.

Okuma describes the current GENOS L400II as compact and built for high-speed operation, with a one-piece cast iron base, a horizontal way system and hand-scraped headstock and tailstock mounting surfaces. It also lists a separated coolant tank for easier maintenance.

Okuma GENOS L400II Specs

Okuma's US page lists these figures for the OSP-P500 configuration. Older L400s and other markets can differ, which is why the next section matters.

Two Axes on Purpose

A turning-only lathe does one thing: it turns. Shafts, flanges, bushings, pins and chucked parts with no milled flats, cross holes or keyways. For that work, live tools and a C-axis are a cost you pay for and never use.

Here's the part most buyers never think about: every axis you add is another thing to maintain, another thing to program and another thing to check on a used machine. A 2-axis CNC Lathe has no live tool drive to wear out, no C-axis brake and no Y-axis slide. If your parts do not need them, the simpler machine is the one with less to go wrong.

The L400 also makes sense as a second-operation or dedicated machine next to a mill-turn. Let the multi-axis machine do the parts that need it, and run the plain turned work on the simpler machine.

What Used Listings Say, and Where They Disagree

Two real listings show why you read a GENOS L400 spec sheet carefully. A 2014 GENOS L400 listed by Used CNC LLC shows a 20.47-inch swing, a 15.3-inch maximum turning diameter, 19.6 inches of machining length, 15 hp, 3,000 rpm, a 12-station non-powered turret and an OSP-P300L control. A 2022 GENOS L400II-e listed by Southern Fabricating Machinery Sales shows a 15.35-inch maximum turning diameter, 20 hp and an OSP-P300LA-e control.

None of this means a listing is wrong. Maximum turning diameter is quoted more than one way, bar capacity is often just the spindle bore restated, and power ratings differ between markets. It does mean you should not compare two L400s on listing numbers alone. Ask for the machine's own data plate and spec sheet.

The Turret: Count the Stations

Both listings above show a 12-station turret. Okuma has offered more than one turret on the GENOS L family, so count the stations in the photos or ask. Twelve stations let you leave more tools set up between jobs, which matters if you run short batches on a turning-only machine.

The L400 shares its static tool holders with other GENOS L machines. If you already run GENOS L300s, your static tooling should carry over. Live tooling does not apply here, because the L400 has none.

Which Control You Are Getting

Every GENOS L400 runs an Okuma OSP control, because Okuma builds its own controls. The generation still matters. Listings show the OSP-P200L, the OSP-P300L and, on later L400II-e machines, the OSP-P300LA-e. The 2022 L400II-e listing includes One-Touch IGF, Okuma's conversational programming.

If your shop runs another control, plan for the change in habits. For more on why Okuma builds both the machine and the control, see Okuma: The Only Builder That Makes Its Own Machine and Its Own Control.

GENOS L400 or L400II?

The L400II is the later generation. The clearest number to compare is the Z-axis rapid. The 2014 GENOS L400 listing shows 985 inches per minute, about 25 m/min. Okuma lists the L400II at 30 m/min (98 fpm). For short-cycle production work, faster rapids cut the time the tool spends moving instead of cutting.

The -e suffix shows up on later L400II machines. In the listings we reviewed, it comes with the OSP-P300LA-e control. Check the control model on the machine, not just the suffix on the nameplate.

What to Check on a Used GENOS L400

• Read the spindle motor plate to confirm the power rating.
• Confirm the control model and back up the parameters and programs before the machine moves.
• Count the turret stations and check that the turret indexes cleanly to every station.
• Check the tailstock: manual or programmable, taper size and quill travel.
• Measure the chuck jaws and confirm the chuck and cylinder size match your bar work.
• Run the spindle through its range and listen for bearing noise.
• Ask what is included: chip conveyor, tool presetter, collet chuck and spindle liners.

If you need milled features on the same parts, look at the live-tool side of the family instead. Our Used Okuma GENOS L300 Meet the Machine covers the M and MYW versions.

The Simple One Is the Point

The GENOS L400 is not a stripped-down L300-M. It is a different answer to a different question. If your parts only need to be turned, it gives you a 10-inch chuck, an Okuma OSP control and a cast iron base, without paying for axes you will never use.

Frequently Asked Questions