Invented Milwaukee’s Sawzall in 1951; designed drills, circular saws, jigsaws, sanders, grinders, and rotary hammers
When Jerome Schnettler joined Milwaukee Electric Tool Co.’s engineering department in 1951, he doubled the department’s size. Chief engineer Edward Ristow was a self-taught one-man engineering department then; he had joined Milwaukee in the late 1930s. From the first project they completed together, the two men helped create an environment of innovation and change at Milwaukee that still guides the company today. In the process, they left behind a legacy of inventions that established Milwaukee’s place as an industry leader.
Milwaukee’s legendary Sawzall is the best-known tool associated with these men. Ristow had been adapting wobble-plate mechanisms to the tool’s design, but he wanted to create a powerful, portable, high-speed saw that would cut wood, metal, or composite materials with a reciprocating action. A number of reciprocating drill attachments were already available, but there were no independent tools based on this technology. Schnettler jumped in and produced all the detailed production drawings for every part in the prototype Sawzall.
The Sawzall quickly became popular among the trades. In 1961, the company introduced a two-speed model. A dial-controlled speed saw was added in 1965, and the company introduced the first double-insulated model in 1973. Ristow retired in 1968 after he and Schnettler had contributed to the designs of the company’s right-angle drills, circular saws, jigsaws, sanders, grinders, and rotary hammers.
Schnettler’s hands-on construction experience, formal engineering education, and drafting talent were a perfect combination for Milwaukee. After working on the Sawzall, Schnettler took it upon himself to modernize the company’s production sample boards by drawing every part of every tool Milwaukee made. Until then, machinists used the actual sample parts for measurements and set up on the plant floor. This was the tool industry’s 1950’s version of converting to CAD.
Schnettler eventually became vice president of engineering and manufacturing, and finally vice president of operations. In 1982, he became Milwaukee’s president.
Both men made lasting contributions to the tool industry that significantly improved the way we work on jobsites. We acknowledge their work by including them in this year’s Hall of Fame.
Robert H. Riley Jr.
Invented first cordless drill for Black & Decker in 1961; developed tools for early space programs
Robert Riley never knew what would happen when he tested battery packs for the first cordless drills in his lab at Black & Decker, so he built a special room to contain the occasional explosions. Nicad battery technology was in its infancy in 1960 when Riley experimented with portable power, so he had to improvise. He created four-cell packs consisting of half-sections of D-cell batteries held together with plastic shrink wrap.
He’d hook them up, max them out, and see how much power he could generate with his DC motors.
These days it may be hard to imagine a world without cordless tools, but the motivation behind Riley’s research stemmed from the day’s demographics. Aluminum storm window installation was one of the biggest markets for contractors in the late 1950s and early 1960s. A contractor would typically show up at a home during the day, plug his tools into a porch lamp adapter, and ask the housewife to turn on the light switch. Then the demographics changed and women entered or re-entered the job market. Homes were vacant during the day, and nobody was there to turn on the power for contractors. Battery power seemed to be the answer, and cordless tools got off to a fairly inauspicious beginning.
Riley faced a tough challenge. In 1960, 120-volt, professional-grade drills put out 200 to 250 watts, Riley’s first 4.8-volt cordless drills could only produce 10 to 20 watts, so he employed new techniques to make his battery-powered tools as efficient as possible. He made the brushes out of silver graphite, designed a 12-to-1 gear reduction to increase torque and reduce gear loss, used a 64-pitch gear with very fine teeth, and reduced the armature pinion’s diameter to 1/8-inch. He also made the rotor out of silver graphite to reduce voltage drop on the comutator, and wired the switch contact with flexible wire so he only needed one stationary contact.
In 1962, Riley filed for a patent on a heavier duty ½-inch drill for industrial use. It had two handles and each housed a battery pack. Early test results proved the tool could drill 567 3/16-inch diameter, 2-inch-deep holes–or run continuously for one hour and 16 minutes–on one charge. Riley’s patent application clearly set the stage for today’s cordless tool designs, stating the intent that the invention produce, ” … the same output torque as that of a conventional ½-inch electric drill.” Riley received a patent for the drill in 1965.
By the late 1960’s Riley had doubled the tool’s power output to 35 to 40 watts. His research took an unexpected turn when Martin Marrietta contracted with Black & Decker to design tools for the national space program in the mid-1960’s. The first tool Riley helped develop was a zero-impact wrench for the Gemini project. The tool allowed an astronaut to spin bolts in zero-gravity without spinning himself. And then came the Apollo moon program. Black & Decker developed a cordless rotary hammer for the mission; it had hollow core-sample drill bits and could operate at extreme temperatures and in zero-atmosphere conditions.
Cordless tools didn’t become widely popular until the 1980s, but Robert Riley stands near the top of the Hall of Fame list for his inventions and the way they changed the tool industry forever.
Edgar P. Anstett
