Select your wrenches wisely

Workers often try to use tools for a task they weren’t meant to do. When that happens, the tool and the task can get damaged, plus the user may be injured.

Richard Wright, president of Wright Tool Company, offers these tips that can help workers get the most out of wrench use:
1. Always wear eye protection.
2. Never use cheater bars or hammers.
3. Inspect and discard bent, worn or cracked tools.
4. Choose the largest possible drive size for the job.
5. Do not use metric sockets on English fasteners or vice versa.
6. Place the socket all the way on the fastener.
7. A box or socket wrench is stronger and less likely to slip off the fastener than open-end, flare nuts or adjustable wrenches.
8. Avoid over-torque. Use a torque wrench to reach the exact torque required.
9. When removing fasteners, do not use a torque multiplier. Removal torque can be twice the tightening torque, which can overload a torque multiplier.

Choose the proper drive size
Most sockets are available in at least three drive sizes. For example, a 9/16" socket is offered in 1/4", 3/8" and 1/2" drives.

A 1/4" drive socket is the least expensive and works in the tightest spaces, but the wrench handle is too short for heavy loads. For perspective, a 3/8" drive socket is 25 percent stronger than the 1/4" drive socket and a 1/2" drive socket is 21 percent stronger than a 3/8" drive.

Handle length is a good guide for wrench selection. Choose one long enough to provide the required leverage, but not so long that fasteners will break from overloading.

If a fastener can’t be turned with the handle size designed to be used with a particular socket, use a larger drive and socket. Hitting the handle with a hammer or using a cheater bar can overload the wrench.

Match the wrench to the fastener
The closer a wrench fits to the fastener, the less your chance of fastener damage. Newer wrench designs spread the load over a larger area of the fastener.

All sockets wear over time and will not fit the fastener as tightly as when they were new. Worn sockets should be replaced, especially when used on high-strength or 12-point fasteners.

Worn sockets are weaker and more likely to round the corners of fasteners. Discard the socket when you can see nut-end wear, if it feels sloppy on a fastener or if the socket’s drive square is sloppy and mushrooming around the square drive.

If you must work on a worn fastener, a 6-point socket works better than a 12-point socket. Or, use an impact socket which is stronger than a hand socket. 

Freeing frozen fasteners
Apply penetrating oil and let it soak in. If the fastener is rusted, tap it with a hammer.

A larger drive with a longer handle may work, but do not use a larger drive handle than recommended because something will likely break; possibly even the user. Never use a cheater bar.

If these tactics don’t work, try an impact gun and impact socket. A slugging wrench, which is built to be hit with a hammer, is another possibility with larger sizes of frozen fasteners.

If you can’t remove a fastener with a socket or impact wrench, you may have to resort to breaking, burning, or grinding.

Published in the May/June 2002 issue of Contractor Tools and Supplies magazine.

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