courtesy IngersollClick image to enlarge

For the right job, the latest generation of solid carbide three-flute drills are unbeatable.

By Kip Hanson

Due to their smaller flutes and limited chip space, three-flute drills might be considered niche cutting tools, good for nothing more than coring out cast or pre-drilled holes in soft, short-chipping materials like gray cast iron. And while some of this statement has merit, the fact remains that, for the right job, these specialty tools can punch holes like there’s no tomorrow.

World class

“These things really fly,” says Paul Larson, product manager for drills and thread mills at Guhring Inc. in Brookfield, Wisc. “When drilling a 12 mm (0.50 in.) diameter hole in a wrought aluminum alloy, for example, you’re looking at cutting speeds of 450 to 600 SFM and a feedrate of 0.3 mm/rev (0.012 ipr) or greater. You can also expect a hole that’s nice and straight, with a reamer-class finish besides.”

Larson is quick to point out that the company’s GS200 series three-flute carbide drills machine much more than aluminum. They’re also quite effective in low carbon and alloy steels, as well as the cast iron mentioned earlier. This makes them a favorite of automakers, heavy equipment manufacturers, and producers of heat exchangers or hydraulic manifolds, where the tool's ability to resist deflection when encountering cross-holes and angled surfaces means greater hole accuracy, improved tool life, and up to 50 per cent higher throughput.

“The drill’s three margins help to keep it centered and eliminate the wandering you might get with a two-flute,” says Larson. “That said, they do require slightly more Z-axis thrust, and it’s especially important to run them at the correct speeds and feeds if you're to generate the correct chip form and ensure good evacuation.”

The SFeedUP campaign

Tim McKnight seconds those views. A product manager at Ingersoll Cutting Tools in Rockford, Ill., part of the IMC Group, McKnight says Ingersoll’s SolidDrill33 delivered double the tool life and productivity when drilling GG25/40 cast iron cylinder blocks at an automotive customer.

In this particular application, the manufacturer applied MQL (minimum quantity lubrication), although McKnight suggests that high-pressure coolant might have improved these results even further. “Coolant pressure is a huge factor in drill life and performance,” he says.

Here again, this was a short chipping material, which McKnight agrees is where three-flute drills work best. He also notes that the manufacturer paid special attention to holding the drill—as he points out on Ingersoll's Machining App calculator, a three-flute drill's power and torque requirements are roughly half again that of their two-flute cousins. "We haven't heard any complaints of the drill spinning or pulling out of the holder, but in the application just mentioned, we used a thermal shrink chuck to eliminate that possibility.”

Fast and nimble

Steven Oszust Jr., the product development manager and lead tool design engineer at Saginaw, Mich.-based Fullerton Tool Co., is a big fan of three-fluted drills and disagrees with the “core drill only” reputation they’ve earned over the years. “Speaking for our AlumaDrill, at least, they’re the exact opposite,” he says. “Where I consider a traditional core drill as more of a workhorse that powers through at relatively low speeds and is used to prepare the hole for a subsequent operation, the 1565 AlumaDrill is almost nimble, with a lighter construction, deeper gullets, and lots of room for chip flow.”

Oszust also disagrees with the “short chipping” limitation of some three-flute drills. As its name implies, the AlumaDrill’s original intent was for holemaking in aluminum components. Yet Fullerton also recommends the tool for plastic, composites, yellow metals such as brass and copper, and even titanium, the last of which is notorious for its toughness and long, stringy chips.

“We offer many iterations of the drill, including stock standards, engineered specials, multi-step combinations, and coolant-thru tools, so the name AlumaDrill is a bit of a misnomer,” says Oszust. “For instance, we apply a special coating for titanium applications, but it’s essentially the same tool. We've also found it quite effective in mild steel. The tool is designed for relatively light chip loads and higher cutting speeds, which together with the drill point’s double chisel angle and high rake, tends to generate a light, whispy chip that evacuates easily.”

Like his counterparts at Guhring, Ingersoll, and other cutting tool manufacturers, Oszust says three-flute drills produce smoother, rounder, and straighter holes than do two-flute drills. He also reinforces what was said earlier about using the supplier's feed and speed recommendations, advice that customers should follow for any machining operation. Says Oszust, “About the only materials we steer clear of with these drills are hardened steels and some of the newer metals you’re seeing used in the automotive industry, like CGI (compacted graphite iron). Three-flute drills have their place, but it's important to remember that there are many other very effective holemaking solutions out there."

www.fullertontool.com

www.guhring.com

www.ingersoll-imc.com

Québec budget earmarks $526M for manufacturing innovation

Quebec-based aerospace think tank Aéro Montréal is giving a passing grade to the Quebec provincial budget, thanks to an important tax credit.

Growth strong, but supply shortages drive record inflation: Canada Manufacturing PMI

The latest IHS Markit Canada Manufacturing PMI has been released, and it shows growth in output, new orders and employment.

Fast But Firm - Profile of Success: Koss Aerospace

by Mary Scianna

Profilesof toolholding success in high speed machining

End mill for composites

Sandvik Coromant's CoroMill Plura compression end mill for composites combines a positive and negative helix design to "compress" the top and bottom of the component edge.

High Speed? Not Really

by Kip Hanson

Forget about the price, solid carbide is the clear winner when it comes to holemaking

SST opens largest NA EDM consumables facility

SST is opening what the company says is the largest North American EDM consumables facility in New Britain, CT. The company held a ribbon cutting ceremony on November 1. The facility is set to open November 18.

Canada, Ontario support auto investment

The Federal and Ontario governments have created a sub-committee under the Canadian Automotive Partnership Council (CAPC) to promote investments in automotive manufacturing in Ontario.

Manufacturers are still essential in Ontario

Despite severe new lockdown rules for Ontario announced January 12, the manufacturing industry will be allowed to continue operating, a decision applauded by Canadian Manufacturers & Exporters (CME).

North America is the cause of supply chain disruption: K+N report

Roughly 80 per cent of the supply chain disruption impacting global trade and frustrating metal manufacturers across Canada stems from congestion issues associated with North American ports, according to a new report from global freight forwarder Kuehne + Nagel.

BDC sets up $250 M fund for legacy industries

The Business Development Bank of Canada (BDC) has launched a $250 million venture capital fund to foster innovation and digitization in legacy Canadian industries including agriculture, resource extraction and manufacturing.

Makino showcases machining technologies

Automation for die and mould manufacturing, high speed machining, EDM advances and machining software developments were among the topics manufacturers participated in at a Makino event held September 15-17 at the company's Auburn Hills, MI, Tech Centre.

OPG picks 5 Canadian firms to bid on $100M dam maintenance

Ontario Power Generation (OPG) has listed five Canadian companies able to bid on future repair, replacement and refurbishment work for large control gates at its hydroelectric generating stations.

GM’s Ottawa plant to close next year

GM has announced that it will close its Oshawa, ON auto plant as part of a global restructuring.

Cutting Splines

Need to make a million gears?

Face milling for high surface finish

In the metalworking industry, ensuring a high-grade surface finish has always been one of the main directions in cutting tool development. This is also true for indexable face milling cutters.

Stay In Touch

twitter facebook linkedIn