Meet the Machine

Used Makino a81: The nx Added Four Inches You Can't See on the Pallet

A used Makino a81 can be one of three machines. The pallet is the same 630 mm square on all of them, and so are the X and Z travels. What changes is the Y column, the spindle and the control, and those three things decide what the machine will actually cut.

Makino writes the name with a lowercase a, and older plates and many listings print it as A81. The spelling changes nothing. The suffix, the Y travel and the control generation change everything, and a listing photo will not show you any of them.

Three Machines, One Pallet

The Makino a81 sat at the top of the Makino 1-Series in 2012. Trade coverage of IMTS that year described it as having the largest pallet in the 1-Series line, a 630 mm (24.8 in) square that carries 1,200 kg (2,640 lb). Every a81 built since uses that same pallet. Here is how the three versions line up.

The first two columns share a frame. The third does not, and the difference is in the one axis a buyer is least likely to measure.

The Four Inches Makino Added in 2014

Makino introduced the Makino a81nx in April 2014. Dave Ward, then horizontal product line manager at Makino, said the machine "builds on the success of the original a81 platform and sets a new standard for large-part machining performance." The headline change was a 100 mm extension of the Y-axis column, taking Y travel from 800 mm (31.5 in) to 900 mm (35.4 in). That is 3.9 inches of reach that sits above the pallet, not on it.

On a horizontal machining center the Y axis is the vertical stroke of the spindle. It sets how tall a part, fixture or tombstone the spindle can reach. Makino puts the gain at 12.5 percent more work envelope and lists a maximum workpiece of 1,000 mm (39.4 in) in diameter by 1,300 mm (51.2 in) tall on the a81nx.

Ward also cited enhancements to the bed and column castings. The standard payload did not change. It is still 1,200 kg (2,645 lb) on the a81nx, with 1,500 kg (3,307 lb) as an option. The nx gives you more height, not more weight, unless the machine was ordered with the heavier rating.

That matters when you are comparing two listings. A 2012 a81 and a 2015 a81nx photograph the same: same pallet, same enclosure proportions, same X. If your fixture work runs tall, the 100 mm is the whole reason to pay for the newer machine. If it does not, it is 100 mm you are paying for and not using.

The M Is the Spindle

In 2007 Makino introduced the Makino a81M with what it called an integral drive spindle. Makino rated it at 744 ft-lb of torque from 0 to 392 rpm and 50 hp from 2,000 to 5,000 rpm, and pitched it at large-diameter rough boring and face milling in tool steel, carbon steel, stainless steel, titanium, cast iron and compacted graphite iron. Dealer listings show an 8,000 rpm top speed on the a81M, a 60-tool magazine and the Professional 5 control.

For scale, a 2012 listing for a standard a81 with an HSK-A100 spindle shows 488 Nm, about 360 ft-lb, of peak torque. The a81M roughly doubles that at the bottom of the speed range, which is where heavy roughing in hard metal happens. It gives up top speed and, judging by a 2007 listing that shows 1,417 ipm rapids on X and Z, some rapid traverse along the way.

In the nx generation, Makino lists the high-torque spindle as an option rather than a separate model. It offers an 8,000 rpm high-torque spindle on the a81nx and says it delivers 50 hp of continuous power, 19 percent more than the previous model. When it is fitted, rapid traverse drops from 50 m/min (1,968 ipm) to 36 m/min (1,417 ipm). A high-torque a81nx carries no suffix on the plate, so the build sheet is the only way to know which spindle you are buying.

The standard spindle moved too. Makino's 2014 release rated the a81nx 10,000 rpm spindle at 305 Nm of duty-rated torque, 45 kW extended-duty and 26 kW continuous, with duty-rated power up 25 percent over the earlier machine. Makino says faster acceleration and deceleration on both nx spindles cut rigid tapping times by up to 30 percent.

Which Control You Are Getting

The a81 crossed three Makino control generations, and the model name does not tell you which one is on the machine.

A 2014 a81nx and a 2017 a81nx can carry different controls, so nx alone does not settle it. Read the pendant, not the plate. The 2012 a81 also shipped with Makino's Geometric Intelligence servo control with Radical Mode, and the a81nx added a GI mode aimed at cutting pocketing time in aluminum billet. Ask which GI features are enabled, and confirm with Makino what support is available for the control generation you are looking at before you price the machine.

Count the Pockets

The tool magazine on an a81 is its own buying decision. Makino's 2012 coverage listed a ring-type 40-tool magazine as standard. Many used a81s are listed with 60 tools. On the a81nx, 60 tools is standard and Makino offers 80, 136, 187 and 299 tool magazines. The 2014 release introduced a chain-type 80-tool magazine with shorter tool-seek times.

For the a81nx, Makino lists a maximum tool length of 690 mm (27.2 in), a maximum tool diameter of 356 mm (14.0 in) and a maximum tool weight of 30 kg (66 lb), or 35 kg (77 lb) as an option. Tool-to-tool time is 1.7 seconds on both generations. Chip-to-chip is listed at 3.5 seconds on the 2012 a81 and 3.7 seconds on the a81nx. Every a81nx magazine includes a tool loading station.

Two machines with the same year and the same suffix can differ by more than 200 tool pockets. If your work depends on running many jobs without a tool swap, count the pockets before you compare the prices.

The Numbers Underneath

The 2012 figures come from Makino's IMTS 2012 coverage. The a81nx figures come from Makino's current a81nx page and its 2014 launch release. Where a cell says to confirm, Makino did not publish the figure in the sources we used.

Listings Get the Z Wrong

Several dealer listings give the a81 a Z travel of 35.4 inches, or 899 mm. That is the X travel copied into the wrong field. Makino and the trade press both list Z at 1,020 mm (40.2 in). One listing for a 2004 A81 shows a spindle speed of 10 rpm, a dropped 10,000. Treat the listing as a starting point and check the travels against the machine.

Where the a81 Sits in the Makino Lineup

The a81 is the 630 mm machine in a horizontal line that also includes the a51, a61 and a71nx, all of which we have listed. For the company behind it, see our Makino brand profile. For another 630 mm-class pallet-changer horizontal, see our breakdown of the Mazak HCN-6000 and HCN-6800.

Used-Market Value

We are not going to put a price band on the a81. There are too few comparable sales in public view, and an asking price is not a market value. What we can say is which factors move the number, in roughly this order:

1. Which a81. The a81nx and its extra Y sit above the a81. The a81M appeals to a narrower set of buyers cutting hard metal.
2. The spindle. High torque or standard, and its rebuild history.
3. The control generation. Professional 3, 5 or 6.
4. The magazine. 40 or 60 pockets is a different machine from 187 or 299.
5. What came out of the cell. Makino has installed the a81nx in MMC2 pallet systems running MAS-A5 cell control for engine block work. A machine pulled from a cell may or may not come with its pallets, so ask.

What to Check on a Used a81

Read the build sheet. Confirm a81, a81M or a81nx, the spindle type, the magazine size, the payload rating and the options. The plate will not tell you all of it.

Get a spindle quote before you bid. On machinist forums, owners report that an a81 spindle swap requires a special Makino installation tool, and one poster describes Makino asking for a refundable deposit on it. Know what a spindle costs you before you know what the machine costs you.

Run the spindle. Bring it up through its range, listen for bearing noise and check temperature. One rebuilder documented an A81 spindle with rough bearings, a worn taper and a damaged front nut after a crash, so inspect the taper too.

Check the support systems. Forum advice on Makino horizontals of this era calls out the spindle oil chiller, the rotary coupling and the radiators.

Measure the Y. If the listing says a81nx, the spindle should travel 900 mm vertically. If it stops at 800 mm, you are looking at an a81.

Cycle the whole magazine and the pallet changer. Run every pocket and swap pallets repeatedly. Watch for hesitation and listen at the changer.

Index the B axis. Run it through a full rotation and check indexing repeatability. On the a81nx, Makino uses a three-roller bearing on the B-axis table.

Plan the rigging. Listings put the machine at about 41,000 lb, and the 2012 footprint was 138 x 215 in before chip handling and service clearance.

Watch a real part run. A test cut proves the spindle, the axes and the control at the same time.

Who Runs One

Makino points the high-torque spindle at iron castings and hard-metal aerospace parts, and the a81M was pitched at titanium, stainless steel, tool steel, cast iron and compacted graphite iron. Makino has also profiled an a81nx running engine blocks in an MMC2 cell. The standard 10,000 rpm machine, with its 50 m/min rapids and GI servo control, fits large aluminum and steel housings, manifolds and multi-face fixture work that needs the 630 mm pallet.

U.S. Parts and Service

Makino's U.S. operation is based in Mason, Ohio. The a81nx is still on Makino's product pages, so the platform has current factory coverage. For older a81 and a81M machines, call Makino with the serial number before you buy and ask about spindle, control and changer parts for that exact build.

Resell CNC Take

Read the Y before the year. An a81 and an a81nx share a pallet, an X and a Z, so the listing photo cannot separate them. Settle the version first, then the spindle, then the control and the magazine. Condition comes last, because condition is the only thing on that list you can fix after the machine is on your floor.

Frequently Asked Questions