Care and Feeding of Pneumatic Tools

March 1, 2003

If tools could talk

By Emily Refermat

If your pneumatic tools could speak, what would they say?

Would they complain of being wet all the time or are they burning up inside? Are there signs of premature aging, perhaps from lack of good preventative maintenance? Compare your care practices to this pneumatic tool preventative maintenance plan and find out.

Dry, clean, and lubricated
The air powering your pneumatic tool is not the air you breathe. Compressing of normal air compresses the moisture in the air as well and moisture can wreak havoc on your tools. Remember to attach a water separator or filter before the air gets to your tools, otherwise the dampness inside your tool will lead to rust — causing bearings to seize, loss of power, and excessive wear on the turbine blades and rotor. If using a water separator, the bleed valve needs to be open, allowing a steady drip of water to drain out instead of “moisturizing” your tools. “Having [an] air dryer on your compressed air system . . . will help eliminate up to 70 percent of moisture found in air systems,” Craig Peterson of U.S. Tool says. Using “a coalesce or standard filter [as well] will aid in removing most all other moisture.” Portable filters are advantageous when working in remote sites.

Clean air is just as important as dry air. Particulate contamination can distress a pneumatic tool and cause shortened life. One manufacturer recommends a 50-micron or other fine filter on the air compression system in order to ensure “fresh” air. No matter what size the filter is, its job is to collect dirt. Left unchecked it can get full, actually inhibiting airflow. Cleaning your filter with soap and water or following the manufacturer’s instructions, then blowing air back through it in the opposite direction will prevent clogging.

Lubrication is often the foremost issue with pneumatic tools. Not just any lubricant will do. Pneumatic tool lubricant (the one specified by the manufacturer) is specially designed to lubricate and cool, then blow through without leaving a buildup (many also have water dispensing agents according to Peterson). Check the level of lubricant often, ensuring an adequate supply is available. If the lubricator is not installed on the air compression system, then lubricate each tool daily. At the end of the day, add the lubricant to your tool, run it for a couple seconds, and let it sit overnight. Again proper lubrication is important. Too little lubrication means your tool is burning up inside, becoming brittle, and may chip; however, too much causes “blow by” and excess oil will splatter on whatever you’re working on. To test if your tool is properly lubricated, hold some white paper (with a hard surface) at the exhaust of your tool for a minute. Look at the paper and decide if the absence of oil means you have too little lubricant or the drips and runs of oil falling off the paper mean you have put in too much.

Without proper care, pneumatic tools will produce less or inconsistent torque, have a shorter blade life, show excessive wear on gears, and have a shorter motor life.

Take a closer look
Examine your pneumatic tools for air leaks between the case and housing and housing and handle or backcap. There should be no cracks in the housing and the housing should not look deformed in any way. The throttle lever should depress firmly and gradually and then return completely, shutting off the motor. Tools with gearing should not make excessive gear noise or rattle. Nameplates and warning labels must be legible. “Annually, a quick disassembly, inspection, cleaning, [replacement of worn parts, and] reassembly will provide many additional years of trouble free service,” Peterson adds.

Air pressure
Keep an eye on the air pressure regulator. Most pneumatic tools require 90 psi for correct operation. Also, know the cubic feet per minute (cfm) of your air compressor system, the average tool consumes between 50 and 75 cfm. Don’t run too many pneumatic tools at the same time off a small system or too far away from the air compressor. This will produce lower flow volumes, altering speed, reducing torque output, or causing inconsistent performance Peterson warns.

Although the pneumatic tool may be in pristine working condition the operator behind the tool needs to know how to use it safely. Wear Personal Protective Equipment (PPE), do not use excessive air pressure, and never clamp the trigger in the on position. Turn off the air-supply and disconnect the tool before installing, removing, or adjusting accessories, when loading, or when performing repairs and clearing jams. Only operate the tool on the workpiece and only use appropriate fittings.

Richard Fowkes, sales director of Kett Tool Co., when asked what type of care a mechanic can give to pneumatic tools to get the most life out of them, said “[t]ools are simply made, [just] clean and lubricate.” Simple, yet important instructions to keep your pneumatic tools clean, happy, and running smoothly. So give your pneumatic tools a little TLC and if one day tools can talk, they’ll say nothing but good things about you.

Additional ReSources
Modern Tool Room
P.O. Box 24774 Gallows Bay
St. Croix, VI 00824

888 Forest Edge Dr.
Vernon Hills, IL 60061

About the Author

Emily Refermat