July 25, 2006 > TechKnow Talk
In 1953, a tiny, three-person company in San Diego, Rocket Chemical Company, was attempting to develop products to protect metals from rust and other corrosion in hopes of marketing them to aircraft manufacturers and the fledgling missile industry. Corrosion protection is achieved by displacing water. Many "water displacement" formulations were tried without much success, until chemist and company founder Norm Larsen concocted an effective formula on his 40th attempt. His notebook is said to have read "Water Displacement, 40th attempt," which was shortened to the more marketable WD-40. This original formula worked so well that it has never been modified, and is still in use today.
The product was wildly successful right from the start. Rocket Chemical supplied WD-40 to a Southern California aerospace contractor, Convair, who painted it onto the external surfaces of its Atlas missiles, where it did an excellent job of corrosion prevention. Convair employees were so impressed that some took cans of WD-40 to use at home. Upon hearing this, Norm Larsen, who must have been a skilled entrepreneur, conceived the idea of placing some WD-40 in aerosol cans and selling it to hardware stores in San Diego. By 1960, Rocket Chemical Co. was selling WD-40 as fast as it could make it.
The company changed its name to match its sole product in 1969, and has been in business as WD-40 ever since. It did not diversify beyond that single product until 1995, when it purchased the 3-IN-ONE oil brand. In 1999, it acquired Lava, a heavy-duty hand soap. In recent years, the WD-40 company has continued to grow by acquisition and new product development, adding several household cleansers and carpet cleaning products. Today, WD-40 employs more than 200 people in 160 countries, and reports sales of more than $200 million annually. The original product is still by far the best seller; one or more cans of WD-40 can be found in 80 percent of U.S. households.
It is pretty amazing stuff. The aged joke says the handyman needs only two tools: duct tape and WD-40. If it moves but shouldn't, use duct tape. If it doesn't move but should, use WD-40. But in fact the myriad uses of WD-40 far surpass the ability to get something unstuck and moving.
The company claims the following basic functions for its flagship product: cleaning, water displacement, penetration, lubrication, and protection. As a cleanser, it removes a wide variety of substances, including dirt, grease, and adhesives. Its water displacement properties keep electrical systems dry to prevent moisture-caused short circuits. It has superb penetration characteristics, which allow it to get into the most tightly coupled joints, freeing frozen or rusted parts. As a lubricant, WD-40 reduces friction to ensure parts in contact move smoothly and "squeak-free." Its corrosion protection capabilities derive from its ability to eliminate moisture and other corrosive agents and to provide a lasting barrier against them.
It will clean just about anything from most painted surfaces without damaging the paint (but always try it on an out-of-the-way spot first to be sure). It will remove bugs, tar, and tree sap from a car. Spray a little in the channels of a garage door for lubrication. Use it to silence a squeaky hinge or chair. It's an effective degreaser, and using it to clean tools or sporting equipment leaves a residue that discourages rust and water damage. WD-40 may damage certain types of plastics, but it is safe for all metal, wood, and rubber materials. The shelf life is so long that no expiration dates are used. The can you bought 25 years ago should still work just fine.
Over the years, users have submitted over 2000 uses for WD-40 to the company, ranging from the clever to the bizarre. Here are a few examples: lubricate wires pulled through a conduit, eliminate squeaks in brake or clutch pedals, recondition leather, repel animals from gardens or trash cans, degrease and lubricate bicycle or motorcycle chains, remove soot from glass candle holders or oil lamps, free cable terminals corroded to battery posts, lubricate zippers, remove gum from carpet, coat a mirror to preclude fogging, remove stains on clothing, clean tires and wheels, unclog shower heads, protect toilet screws and plumbing fixtures from rust, and remove lipstick, ink, crayon, etc. from upholstery. The manufacturer does not guarantee these suggestions will work, and recommends common sense and attention to instructions and warnings on the can.
Let's return to the original question of its composition. The answer is: only a few people know for sure, and they aren't talking. The formulation is a proprietary, closely-guarded company secret. But some ingredients are obvious. WD-40 is petroleum-based. That's why it can damage certain types of plastics. The Material Safety Data Sheet, which must be filed by manufacturers of industrial chemicals, lists the only hazardous ingredient as Stoddard Solvent, which is an aliphatic petroleum distillate.
Chemists have speculated that liquid WD-40 is probably about 70 percent Stoddard Solvent. It also contains a lubricant (possibly also a petroleum distillate), a corrosion inhibitor (likely some type of oil), and a wetting agent (this is what facilitates penetration into tight joints). Carbon dioxide is added as an aerosol agent, or propellant. Other components may well be present in small amounts.
The TechKnow Guy enjoys the fact that, even with all their fancy analytical tools, chemists can't determine for sure what's in WD-40. Like a magic trick, knowing how it is done would remove the mystery and make it less fascinating. Whatever is in it, Norm Larsen's 40th attempt yielded one of the most useful products ever created.