Meet the Machine

Used Okuma GENOS L300: The W Takes the Tailstock

We have two 2014 Okuma GENOS L300s on the floor right now. An L300-M and an L300-MYW. Same year, same 10 inch chuck, same A2-8 spindle, same 12 station turret.

Walk to the right hand end of each machine and they stop being the same lathe. The M has a tailstock. The MYW has a second spindle in that spot, and no tailstock at all.

That is the trade the letters describe. The Y adds off center milling. The W adds a sub-spindle, which lets an L300 finish both ends of a part in one cycle, and it takes away the one thing that holds up a long shaft. Which machine is worth more depends entirely on which of those your parts need.

Our guide to reading a GENOS L model name decodes the whole family. This piece is about the L300, and the two on our floor.

Two 2014 L300s, Side by Side

Here are the two machines by configuration, using Okuma's GENOS catalog for the factory figures and our listings for what is on each machine.

Five of the eight rows are identical. The other three are the whole story: a Y axis, a sub-spindle, and the tailstock the sub-spindle replaces.

What the W Buys

The W is Okuma's suffix for a sub-spindle, an opposed second spindle that takes the part from the main spindle. On our MYW it travels 20.47 inches. Okuma's catalog lists it at 6,000 rpm, 7.5 kW for 30 minutes and 5.5 kW continuous, with 48 N·m of torque.

It lets the machine cut the front of a part on the main spindle, hand it across, and cut the back on the sub-spindle, without an operator flipping it. On a part with features on both ends, that removes the second setup and the second fixture, and the alignment risk that comes with rechucking.

What the W Costs

The tailstock. Our GENOS L guide puts it plainly: a sub-spindle machine has no tailstock, because the sub-spindle occupies that space.

On short, chucked work that does not matter. On a long, slender shaft it matters a great deal, because a part hanging out of the chuck with nothing supporting the far end will deflect and chatter under the tool. The M can put a center in the end of that shaft. The MYW cannot.

So the question is not which machine is more capable. It is which kind of part you run. Parts that need back working favor the MYW. Shafts that need support favor the M.

Resell CNC Take

Price the W against your parts, not against the M. If you flip a lot of parts by hand today, the MYW earns its premium in setups you stop doing. If you turn long shafts, the M is the more useful lathe, and the extra letters on the MYW are capability you would pay for and never use.

The Y Axis Is 100 Millimeters

Okuma's catalog lists 100 mm of Y travel on the L300-MY, plus and minus 50 mm, on what it calls a double slide system. That is roughly 3.9 inches.

It is enough to mill a flat, cut a keyway or slot, or drill a hole off the centerline, all of which a C axis alone cannot do cleanly. It is not a milling machine. Treat the Y as a way to finish features that would otherwise need a trip to a mill, and check that your features fit inside the 100 mm.

The Live Tools

Both of our L300s have live tooling. Okuma's catalog lists the L300-M milling tool spindle at 4,500 rpm, 7.0 kW for 30 minutes and 3.3 kW continuous, with 24 N·m of torque, driving a V12 NC turret that indexes in 0.1 seconds.

Okuma also published what that turret will cut. In S45C carbon steel, its L300-M machining examples reach a 20 mm end mill, a 14 mm drill and an M16 x 2.0 tap. The C axis positions to plus or minus 0.015 degrees with plus or minus 0.007 degrees repeatability.

Those are the limits to plan around. Cross holes, flats and tapped holes are well inside them. Heavy face milling is not what this turret was built for.

The Numbers Underneath

Specifications vary by year and build, so pull the sheet for the exact serial number in front of you. These are the figures from Okuma's GENOS catalog, with dimensions confirmed against our listings.

One line needs a note. Okuma's early GENOS catalog lists 11 kW for the 30 minute rating on the 10 inch M machines, while Okuma's 2018 press release puts the L300 at 15 kW for 30 minutes and 11 kW continuous. Read the motor plate on the machine rather than trusting either number.

Built Before the Rename

Okuma's English launch announcement for the GENOS L is dated January 2011. The line is Okuma's value range, built by Tatung-Okuma in Taiwan. In October 2018 the L300 became the GENOS L3000-e. Okuma's release tied the change to engineering: an integral spindle motor in place of the belt drive, more rigid guideways, thermal compensation as standard, and spindle power up from 15/11 kW on the L300 to 22/15 kW.

Both of ours are 2014 builds, four years before that change, with the original belt driven spindle. The three digit name is a quick first clue to a GENOS L's age, but 2018 was a transition year, so on a 2018 machine read the nameplate and the spindle spec rather than the model name alone.

Which Control You Are Getting

Okuma introduced the OSP-P300 control in September 2012, and our GENOS L guide places GENOS L machines from roughly 2013 to 2016 on the OSP-P300L or P300L-R. A 2014 L300 should be on one of those, but confirm the exact string on the control's identification screen or the cabinet nameplate.

The OSP runs on a Windows PC with a hard drive. Before you buy, get a full backup of parameters, ladder, tool data and programs, and power cycle the control while you are standing at the machine.

U.S. Parts and Service

Okuma America supports these machines through a distributor network of roughly three dozen locations across the United States, Canada and Mexico, and its Global Repair Center in Charlotte, North Carolina provides legacy parts support. More on the company in our Okuma brand profile.

Two on Our Floor

2014 GENOS L300-M. Okuma OSP control with Ethernet and USB, 12 station turret with live tooling and C axis, MT5 tailstock, a Royal QG65 collet chuck with a 3 jaw chuck included, Su-Matic face and cross live tools, parts catcher, tool presetter and chip conveyor.

2014 GENOS L300-MYW. Live tooling, Y axis and W axis sub-spindle, high pressure coolant, parts catcher, tool presetter and chip conveyor, with Su-Matic and MD live tools, a Su-Matic main and sub face tool, two boring holders, a WTO quad static block and spindle liners from 1.0 to 1.625 inches.

Two different answers to the same question, on the same floor. Inventory changes, so check the Okuma brand page for what is available today.

Used-Market Value

Configuration. On a GENOS L, the suffix drives the price more than the year. An MYW is the top of the family and priced that way, which is only a good deal if your parts use the Y and the W.

Control and backup. The control generation, and whether a current backup comes with the machine.

Tooling. Live tool holders and static blocks are expensive to assemble. A machine that comes with a working set for your parts is worth more than the same machine bare.

Automation fitted. Bar feeder or bar feeder interface, parts catcher and presetter. A bar feeder and an interface are different line items.

What to Check on a Used GENOS L300

Photograph the turret face. Our GENOS L guide found the live tool interface on the sub-spindle models listed as BMT in some catalogs and VDI40 in others. Match the photo to a holder catalog before you buy a single live tool.

Check turret repeatability hot. Index all 12 stations after the machine has warmed up and check size scatter. On an Okuma lathe this shows up as inconsistent parts, not an alarm.

Run the live tools and C axis. Through their speed range, listening for bearing noise and checking C axis indexing.

On an MYW, check the Y and the handoff. Run the Y through its full 100 mm, then run a part through the transfer to the sub-spindle and confirm it seats and runs true.

On an M, check the tailstock. Travel, quill and alignment to the spindle.

Read all three hour counters and get the control backup.

Who Runs One

The L300-M suits a shop turning shafts, pins and fittings up to 300 mm across that need cross holes, flats or tapped features, and sometimes need a tailstock under a long part. The L300-MYW suits a shop running parts with features on both ends, where flipping each part by hand is the bottleneck. We made the broader case for that kind of machine in Done In One, and for another Okuma turning center, see our Meet the Machine on the Okuma LB4000.

Frequently Asked Questions