Air-powered tools lead a tough life on farms. They’re used heavily for a day or two to change dozens of sweeps on a field cultivator or replace knife guards on a small grain platform, then left idle for weeks at a time. Making their lives even more difficult, the infrequent times they’re
intensely used are often under dusty, gritty circumstances. When they’re not in use, air tools often get buried in the clutter atop workbenches or become a footrest on the passenger-side floorboard of a farm truck.
While abuse and neglect can damage air tools, their greatest enemies are dirt and moisture. Air-powered tools have precision internal components that spin at thousands of revolutions per minute. Dirt and grit can do great harm to internal components spinning at high speed at close
tolerances. Moisture is equally damaging because it interrupts the layer of lubrication that keeps those internal components from grinding themselves into metal filings.
Make tools last longer. "Excluding" and "including" are the keys to air tool longevity. Excluding dirt and grit can be as simple as using your breath to blow dust and debris from the female coupler on air hoses before coupling them to air tools. In a perfect world, users would flush male and female air couplers with brake cleaner or contact cleaner every time they’re connected, but few of us live in a perfect world.
Between uses, especially if an air tool will be stored in a dirty environment, cap the male air inlet on air-powered tools. Auto parts stores offer packages of assorted rubber caps for vacuum lines. Select a rubber vacuum cap that fits snugly over the male air inlet to keep debris out of air tools.
Moisture is the other villain. Every time air tools are connected to a compressed air delivery system, there is a risk of injecting moisture. Air is heated as it is compressed. When the heated air enters the metal storage tank or passes through distribution lines or hoses, the humidity in that heated air condenses on the cooler surfaces. Air movement from the storage tank and through delivery lines literally injects drops of condensed moisture into air tools.
The first line of defense against moisture damage to air tools is to install water filters in the lines as close as possible to where the air tools are attached. The second defense, which is the "including" part of air tool maintenance, is to regularly add lubricant to the intake port of air tools.
Special water filters/oilers installed in air lines accomplish both tasks automatically while an air tool is being used. I prefer to put a few drops of air tool oil in the air inlets of my air tools before every use so I know they’re well lubricated every time I pull the trigger.
If an air tool is going to sit idle for a few weeks between uses, add a few drops of lubricant to the air inlet when you’re done using the tool. Just be sure to reconnect the tool to compressed air and hit the trigger a few times to distribute the lubricant throughout the tool so all internal components are protected while the tool is idle.
It is important to use only lubricants that are approved for air tools. I can speak from (expensive) experience that penetrating oils such as JB-80 and WD-40 are not good for air tools. Those products are designed to evaporate and leave only a thin, minimal residue that is inadequate for protecting the high-speed, precision innards of air tools.
Beware of air tool lubricants advertised to do more than lubricate air tools. Glen Simpson, a technical support representative for Stanley-Bostitch, warns that if an air tool oil brags that it cleans, degreases or drives out water, don’t use it. These products may contain isopropyl alcohol or solvents that attack rubber O-rings and seals. The best oil is the one recommended by the air tool manufacturer.
Finally, if the outside of your rubber air delivery hoses start to flake or crack, replace them. If the outside rubber is failing, so is the inside liner, thereby sending pieces of rubber into air tools to damage precision components.
Cool Tool of the Month
If air tools aren’t available, arm power is the only way to break loose tight nuts or bolts. Snap-on Inc.’s ¾", 41"-long, one-piece breaker bar, pictured below, is no longer available, but combining the company’s L8112A ¾" breaker bar head with its 36"-long L872RM handle and L872H 19" extension produces a 55"-long monster breaker bar that will break down and fit in many toolboxes.