Benchmark Carbide is an innovative grinding company that is a manufacturer of carbide endmills and reamers. The company is based in Springfield, Massachusetts, USA.
“We have a very strong brand name and we have been making excellent tools since 1996,” says Benchmark Carbide owner Paul St. Louis. Since 2001, the company had slowly improved its performance – until recently when orders for its patented endmills dramatically increased. It takes a lot to keep up with that kind of demand. Paul counts on his 11 ANCA CNC tool and cutter grinders with automatic loaders. “We run our ANCA machines 24 hours a day, seven days a week, producing around 1300 endmills a day. On a good weekend we can make over 3000 endmills,” Paul said.
The Benchmark Carbide factory
Automation significantly increased production
It is a neatly organised, compact shop. “Every machine is fitted with automatic tool loaders and we run a lean shop with only 18 people on the floor. Dual wheel packs and in-machine dressing on the ANCA machines means we have flexibility and the capability to operate long hours unattended, producing superior tools without interruption.”
Three of the machines are the production-oriented TX7s with auto loaders running larger tools to 1.5” (38 mm). Eight RX7s run the smaller tools from .006 to .500.” “With eight manual machines, I could not do a third of what we produce now,” Paul said. The automation and lean shop organisation permit Benchmark to operate as a low cost producer and to offer the market some highly innovative tool designs that reduce the cost of machining aluminium and other material. The TX7s feature a powerful 49HP (37kW) 10,000 RPM spindle, an automatic wheel changer, auto-loading system, and a 3000 RPM headstock. ANCA’s ToolRoom tool and cutter grinding software drives the machine.
Change over of wheel pack, coolant manifolds, work holding and loader pallet on the TX7 can be done with minimal machine down time. Other brand machines require from 15-20 minutes to several hours for changeover to produce another type of tool. For the TX7, wheel packs and corresponding coolant manifolds are prepared off-machine and quickly exchanged to grind a new tool.
Benchmark boss, Paul St Louis
How Benchmark reduce vibration in the tools they make
Benchmark’s customers look on them as innovators. They make endmills for machining aluminium a little differently than others do. And they work exceptionally well, outperforming other brands.
Most tools by other manufacturers are made with a cylindrical margin, where the shank is the OD of the tool that is cutting. Endmill makers typically flute it out and leave behind a narrow - often .003” wide margin. This is often difficult to hold. If it is too wide, it will push away, too narrow, and you get chatter. “With our ANCA machines we run the grinds on the OD: primary, secondary and a ground-on edge prep which reduces chatter and vibration and we can control the thickness of it to .0015” and .002” wide,” Paul said, “so when the tools are milling aluminium they do not squeal or chatter. Machining is consistent and high quality. The tool repeats. And we have two grinds on the fluting to move the chip a little better.”
The company makes two-, three-, four- and five-flute carbide tools for high-speed machining of aluminium. Variable helix mills are a Benchmark specialty, starting with a 45-degree helix and ending at a 60-degree helix.
The helix design reduces vibration in the tool. “With the ANCA machines producing five-flute tools we can remove .0001” per tooth and over 50% of the tool diameter. With that tool in a 10,000 RPM machining center spindle you could run 500 ipm (12.7 m/m),” Paul pointed out. The edge prep by Benchmark goes around the radius and does the end in a single grind. The machine and software capability lets Benchmark maintain its edge. ANCA ToolRoom software is key to allowing Benchmark produce the variable helix.
Benchmark can produce tools in a single set-up
The direct drive, high-speed 3000 RPM work head (A-axis) of the TX7 allows users like Benchmark to include cylindrical grinding operations in the tool grinding process without changing the set-up, and to fully grind stepped or tapered blanks to the final tool. This means tools can be produced complete in a single set-up, minimising production time for many tools that formerly may have required two operations to complete.
The ANCA TX7s at Benchmark use the patented Big Plus wheel mounting system which contributes to high precision running of the grinding wheels. The system, superior to a conventional tapered holder, provides a more complete and concentric contact plus flange contact. The resulting rigid assembly nearly eliminates runout and deflection, and benefits wheel life, surface finish, and part tolerance.
Mounted to the back of the chuck on the TX7’s high-speed work head, the dresser roll is easily accessed or introduced to the wheels with minimal axis strokes for in-process dressing. On the TX7s, the loader is mounted behind the machine and has its own control panel to enable quick, safe set-up requiring only one operator. The loader brings the tool into the machine on a pneumatic carriage while the headstock automatically positions itself to receive the tool in a rapid tool change cycle.
The CNC wheel changer on the TX7s allows Benchmark to apply two wheel packs to one application, accomplishing more operations in a single set-up. Mounted on a manifold, coolant piping changes with the wheel packs, so that coolant flow is always tuned to the wheel in use for optimum coolant application.
Software is the key
Clayton Pirie manages the ANCA machines at Benchmark. He says he is always learning as ANCA is constantly enhancing its software and providing updates to the shop.
“ANCA’s user-friendly software has enabled us to produce a number of innovations that other tool makers don't have,” Clayton said. “The CIMulator3D lets us lay out the whole tool off-line without wasting grinding machine time. We can dream up a tool and see if we can make it before we ever get to machining. It’s an innovator’s best tool.”
ANCA’s CIMulator3D provides an off-line tool development environment which enables the efficient design of new tooling and the required manufacturing process, avoiding loss of production. Set-up time for new tools is dramatically reduced, and production can begin more quickly. In addition to being used to program tools offline, the CIMulator3D is also on the machine's operator panel, allowing operators to simulate and check tools prior to grinding.
Paul observes: “When we did half the volume, it seemed more stressful on the shop floor. Today, there are only three set-up people in each shift, yet it’s a calmer atmosphere. We are producing much more with much less stress, thanks to the ANCA machines. The machines are doing consistently high quality work over long runs.”
Find out more about Benchmark Carbide at www.benchmarkcarbide.com
Find out more about ANCA products at www.anca.com
Written by Dave Arnesan, USA.
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