Machine Design

Inventor's Corner: A More-Versatile Set of Box-End Wrenches

The “Peanut Wrench” set from Jack Nguyen includes box-end wrench fittings (which work like open-end crowfoot wrenches) that can be used as-is (like a thumbwheel wrench or socket) or mated with one of a few handles. The end of each handle has a square drive (¼, 3/8, or ½ in.) that goes into a square recess on the box-end wrench fittings. The box-end wrench fittings are sized to fit SAE, metric, E-Torx, and spline-style fasteners. The wrenches provide a versatile and complete, yet compact, set of tools to tackle many wrenching jobs.

Of course, says Nguyen, there are already many kinds of wrenches available to loosen or tighten nuts, screws, bolts, and fasteners. Current types include stubby, flexible, S-shape, half-moon, open-end crowfoot, and thumbwheel ratchet with sockets. However, it is important to use the correct wrench for a job to avoid damaging the fastener, while ensuring user safety, and reducing fatigue over extended use. The trouble is that purchasing the many different types of wrenches can be costly and the ensuing collection can require lots of storage space. Also, many wrench sets are housed in large, cumbersome toolboxes, which are difficult to lug around in the field.

Not only is the Peanut Wrench set more versatile, Nguyen says manufacturing them uses less material and smaller production tooling and forging dies. Also, there is less energy expended in producing and transporting them to market.

He says he got the idea when he saw a set of open-end crowfoot wrenches while shopping for hand tools. “The thought came to mind that wrench sets could be made more like the ubiquitous socket and ratchets sets, where each socket does not have its own permanent handle.” He then worked up the idea using standard wrench samples, a digital caliper, and SolidWorks 3D CAD software.








“I showed a concept drawing to a mechanic acquaintance and he really liked it and immediately understood the benefits,” says Nguyen. “With all the hand tools that exist, he was amazed that this was not already being made and sold. As far as I know, the design is new.”

Nguyen recently submitted his patent-pending design to Craftsman and Snap-on to review for licensing. Contact: Jack Nguyen, San Clemente, Calif., [email protected]

Are you (or do you know) an engineer who has come up with a sophisticated invention in your spare time? Want to get your idea showcased in Machine Design magazine? Contact [email protected] or (216) 931-9242.

Watch the short video about Peanut Wrenches!

© 2011 Penton Media, Inc.

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