CENTERLESS GRINDER
20x12
Hi-Accuracy
With FANUC Collaborative Robot
Clean-sheet engineering. The largest Royal Master ever built. Making its world debut at IMTS 2026.
The 20×12 has been two years in the making, engineered from a blank page. It is the first large-format centerless grinder built on an entirely new platform in 30 years. At IMTS, it debuts grinding a transmission shaft loaded by a Fanuc collaborative robot, and invites every visitor to look inside and understand exactly how it was built and why.
20″x 12″
20″ DIAMETER X 12″ WIDE GRINDING WHEEL / 12″ DIAMETER REGULATING WHEEL
1,800,000 LBS
OF STATIC STIFFNESS
8,800 LBS
ENGINEERED MACHINE WEIGHT
UNDER 1 MICRON
GRINDS TO UNDER 1 MICRON ROUND AND STRAIGHT OVER 12″
• ORIGINAL SERIES
THE STORY BEHIND THE PART
THE SOLUTION FOR YOUR CHALLENGE
YOU NEED A LARGE, CENTERLESS GRINDER. YOU'RE DONE REBUILDING 1950'S IRON.
You’ve been running Cincinnati machines and need a modern replacement.
The 20×12 was engineered to match the static stiffness, wheel size, and feel of the Cincinnati machines your operators know, with all modern engineering underneath. No adaptation. No bolt-ons. Built right from the start.
You want to grind large, demanding parts with real precision.
Just under 2 million pounds of static stiffness. 9 nanometer glass scales. All-servo controlled, no hydraulics, no warm-up time. Move a quarter micron on your part: that’s what it moves.
You’re choosing between new iron and a rebuilt carcass
• . There is no equivalent on the market that starts from scratch at this scale. The machine at the show didn’t need to be power-washed before it was built. It was engineered, not reassembled.
TECHNICAL SPECS
BUILT TO A DIFFERENT STANDARD
STATIC STIFFNESS
1,800,000 lbs
Back in the day, all the data for the Cincinnati centerless grinders pointed to weight and static stiffness. That gave us a waypoint in our design. We didn’t just match the static stiffness and weight of the Cincinatti machines, it is the engineering that is built into the system on top of those two brochure points that sets the machine apart.
WHEEL SIZE
20″ x 12″
20″ diameter x 12″ diameter Regulating wheel. We are right in-between the 24×10 and the 20×8 wheels, but it is just the right fit. Using existing cincinatti wheel mounts you can use your current wheels and mounts on this machine.
DIAMETER POSITIONING
0.000,009 Nanometer
Not every need requires this level of precison, its nice to have it but we offer a simple thrufeed version of thie machine for your more basic thrufeed applications. Using a pulse generator, one micron diameter adjustments can be made and still take advantage of the dual slide system.
SPINDLE DESIGN
Hard Bearing / No Outboard
Timken hard bearing headstock design delivers high rigidity under heavy loads without requiring an outboard support
MACHINE BED
Starrett Granite
Granite surface plate machine bed lapped to .0002″ flatness
AUTOMATION
Seamlessly Integrated
Seamlessly Integrated | From high-volume step feeders to pick and place or robotic cells, the 20×12 couples with all types of automation. Gauging with machine feedback is commonly added to complete the system.
WHAT SETS IT APART
THE HIGHLIGHTS
1,800,000 lbs of Static Stiffness
We heard from Cincinnati owners — weight and static stiffness matter in an XL centerless. We delivered. Within 300 lbs of a Cincinnati OM and matching the static stiffness. We listened.
20" x 12" Grinding Wheel — 12" Regulating Wheel
The largest wheel in the Royal Master lineup. The 12″ wide face handles large-diameter, long-reach parts. Your current Cincinnati wheel mounts and wheels are a direct fit to this platform. Current mounts also fit with an optional adapter.
9 Nanometer Glass Scales — 1/4 Micron Positioning on Upper and Lower Ram
The precision Royal Master is known for, now on the XL platform. Large parts, tight tolerances, quarter-micron repeatability.
All Types of Automation Supported
From high-volume step feeders to pick and place or robotic cells, the system couples with all types of automation. Royal Master engineering on the machine and automation makes for a seamlessly integrated system. Gauging with machine feedback is commonly added.
Hard Bearing Headstock Design — No Outboard Support Required
Engineered in conjunction with Timken for a spindle that delivers high rigidity under heavy loads without an outboard bearing. A rigid solution confirmed through modern engineering tools.
Dual Slide System — Upper and Lower Ram Beds
Independent upper and lower ram beds for maximum setup flexibility and process control on complex applications.
Granite Surface Plate Base — Lapped to .0002" Flatness
Same precision foundation as the Hi-Accuracy line. Thermal stability and surface reference built into the machine, not compensated for afterward.
ENGINEER
DEEP DIVE
Take a deep dive into the engineering of our newest centerless grinding system. Learn about the static stiffness calculations and all the robust engineering that makes this an exceptional machine — one that even the most hard-core Cincinnati centerless fans will enjoy working on. At Booth 6626, a second 20×12 is available for discussion with all guards and way covers removed, giving you unlimited access to every component.
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