USING HAND TOOLS SAFELY

by Richard B. Wright, Chairman, Wright Tool Company

Safety, getting the job done and costs are all very important—but in just that order. Shortcuts, substitutions and the use of cheater bars are not worth the risks involved. The cost of a few additional tools is far less expensive than the cost of an accident and the accompanying pain and delays.

The following recommendations provide basic considerations for safety. Although you may be familiar with some of these tips, it's always a good idea to review them-and brush up on the ones that are unfamiliar!

GENERAL TOOL SAFETY TIPS
1. Always wear safety goggles to protect your eyes.
2. Never use cheater bars or hammers.
3. Inspect and discard bent, worn or cracked tools.
4. Use the correct drive size. Choose the largest possible drive size-it is stronger and safer.
5. Use the correct size socket. Do not use metric sockets on inch fasteners or vice versa, because the fit is not good enough.
6. Place the socket all the way on the fastener.
7. The safest wrench is a box or socket type because it is stronger and less likely to slip off the fastener. Open end, flare nuts and adjustable wrenches are not as strong as the corresponding sizes of box and socket wrenches. Open end, flare nut, and adjustable wrenches are not intended for heavy loads such as breaking loose frozen fasteners or final tightening.
8. Avoid over-torquing. A torque wrench will permit tightening to the exact torque required for best performance and safety.
9. Do not use a torque multiplier when removing fasteners. Because removal torque is often more than twice the tightening torque, a torque multiplier can easily be overloaded.

CHOOSING THE PROPER DRIVE SIZE
Most sockets are available in at least three drive sizes. For example, a 9/16-in. socket is offered in 1/4-, 3/8- and 1/2-inch drives. A 1/4-inch drive socket is the least expensive and will work in the tightest space, but the handles are too short for heavy loads. If the handles were longer, the drive square would twist off before the fastener was fully tight or a tight fastener was removed. The 1/4-inch drive socket is ideal for low-torque applications such as electrical work or in close quarters behind automobile dashboards.

A 3/8-in. drive socket is 25 percent stronger, but also .022 inches larger in diameter than the 1/4-inch drive socket. A 1/2-inch drive socket is an additional 21 percent stronger and .027 inches larger in diameter.

Most of the time, the best way to choose a drive size is by choosing a drive with handles long enough to provide the required leverage, but not so long that the fasteners will break from overloading. Ideally, sockets should be designed so that each larger drive has stronger and larger sockets. This provides a wide choice of tools for a variety of fastener strengths from copper electrical fasteners to hardened alloy steel fasteners.

Special care should be taken when using the smallest sockets of a particular drive. A hard pull on the handle may overload the socket and/or the fastener. Remember, too, that the strength of larger sockets of a particular drive are limited by the drive square and are, therefore, not appropriate for high-strength fasteners such as Grade 8 bolts or 12-point fasteners.

Industry standards dictate the appropriate handle lengths for each drive. If a tight fastener can't be turned with one size handle, the safe procedure is to use a socket of a larger drive and the corresponding longer handle. Hitting the handle with a hammer or lengthening it with a cheater bar may overload both the socket and the handle, and is never recommended.

WRENCH OPENINGS
It is very important that wrenches provide a close fit. A close fit ensures that they are stronger and do not damage the fastener. Newer designs of wrench openings, such as the Wright Drive, are much better at spreading the load over a large area and avoiding rounding the corners of fasteners. In addition, quality manufacturers make sockets as close to the fastener sizes as possible.

SPOTTING WORN SOCKETS
No matter how good a socket is, the fit on the fastener becomes worse as the socket wears. Therefore, sockets should be removed from service when they become worn. This is particularly important when working with high-strength or 12-point fasteners. Look for wear in the nut end-if the difference is apparent, it should not be used.

Another clue that a wrench is worn is when it feels sloppy on a fastener. Likewise, if the drive square is sloppy or shows signs of mushrooming around the square, the socket should be replaced. Worn sockets are not only weaker and less likely to do the required job, they are also more likely to round the corners of fasteners.

The same points regarding the opening of the socket also apply to the fastener. If the fastener head is worn or rusted, it will not allow good engagement. Normally, the mechanic does not have a choice. One precaution, however, is not to reuse fasteners with damaged heads and to recognize and take extra care in turning fasteners with rounded or rusted heads.

The use of 6-point sockets is often appropriate since they work better on worn fasteners than 12-point sockets. Impact sockets are stronger than hand sockets and can be used in place of hand sockets for tough jobs.

WHEN THE FASTENER CAN'T BE TURNED
The first step in freeing a fastener that can't be turned is to apply penetrating oil and let it soak in. If the fastener is rusted, tap it with a hammer to try to break it loose. If there is room, a larger drive with a longer handle may work. Use of an adapter with a larger drive handle is not recommended, as something will most likely break, possibly even the user. Again, never use a cheater bar.

Next, try an impact gun and impact socket. This combination can deliver a higher torque than can be safely done by hand to the same size opening. Another advantage is that the user won't go sprawling if the fastener suddenly turns or breaks, which are distinct possibilities when working on a frozen fastener. A slugging wrench, which is designed to be hit with a hammer, is another possibility with larger sizes.

To keep fasteners from becoming frozen, replace worn ones so the wrench has something to work on. It's equally important to replace worn out wrenches so that the strongest and safest wrenches are always available in a tool set. High quality wrenches perform better, last longer and are safer.

If it is impossible to remove a fastener by turning it safely, there are other ways to remove fasteners such as breaking the nut, burning, or grinding. Remember, it is not your fault if the fastener is damaged or corroded to the point it can't be turned. Nor is it your fault if the design engineer selected an inappropriate fastener or placed it too close to obstructions to allow for proper removal. It usually takes less torque to assemble a joint than to disassemble a joint, so it is perfectly possible to build something that can't be safely taken apart by a wrench.

Taking the time to review safety issues and tips is the first step in preventing possible accidents and mishaps with hand tools. For a safety video offering additional training and advice, contact the Wright Tool Company at (800)321-2902.

SAFETY TIPS FOR IMPACT SOCKETS
1. Always wear safety goggles.
2. Use only impact sockets on impact guns. Never use chrome sockets on impact guns.
3. Never exceed a gun pressure rating of 90 psi.
4. Don't dwell longer than necessary to get torque.
5. Put the socket on the fastener before starting the impact gun.
6. Do not hold impact sockets, universal joints, or extensions while impact tools are running. Serious hand and wrist injury can occur.
7. Use adapters only for special applications-not for general use.
8. Pay attention to the joints between the gun and fasteners for less loss of torque and less wear.

MORE SAFETY TIPS FOR HYDRAULIC WRENCHES
1. Hydraulic wrenches are preferable to impact guns for installing large fasteners because the torque can be controlled.
2. Be extra careful with these tools because of the ease with which very high loads can be involved. Follow all work instructions and safety precautions carefully.
3. Carefully inspect tools before use for wear or cracks.
4. Good fit of the wrench on the fastener is essential.
5. Do not tighten a fastener beyond the specified torque. Removal torque may be several times tightening torque so that an over-tightened fastener may be impossible to remove, particularly if threads are damaged or corrosion has joined a bolt and nut together.
6. In removing a fastener, be careful not to apply so much torque to the fastener that it breaks. Take proper safety precautions so that no one is injured if the fastener or overloaded wrench is damaged.
7. Impact guns or slugging wrenches are preferable for difficult-to-remove fasteners.

Article appeared in Construction, April 22, 2002 edition.

About the Author:
Richard B. Wright is chairman of Wright Tool Company, a leading manufacturer of professional-quality sockets and wrenches. Located in Barberton, Wright Tool manufactures more than 3,600 tools for the industrial, contractor, and MRO markets.

Mr. Wright holds a degree in Mechanical Engineering from the California Institute of Technology and an M.B.A. degree from the University of Pennsylvania Wharton School. A licensed engineer, Mr. Wright holds several patents in the field of hand tools and electrical instrumentation.