Originally Posted by
manicmike
Have you had a bad experience with it?
I use WD-40 All the time. I buy it in 1 gallon cans and I have two onsite now. I use it with a "green scrubbie" for removing rust off of armor. It is great for cleaning metal of ingrained crud and water and old oil.
WD-40 (Water Displacing Formula #40) is a surface tension breaking penetrating fluid. (NOT an oil)
Oil is a high surface tension lubricant (clings to metal to keep it cool and slick under friction)
If you want to see the effects of surface tension breaking, fill a glass carefully as full as you can make it, so the water is even slightly above lip of the glass in the middle and surface tension is holding it in place. Then add 1 Drop of liquid dish soap (or WD-40) and the surface tension of the water above the lip is released and it runs down the sides of the glass. Until you remove ALL of the soap or WD-40 you cannot make the water bulge above the lip again.
So, when you do that to a crevice with crud in it, you may get the crud out but you also leave a coating of surface tension breaking chemical.
Now, when you add Oil or Tri-Flow, it has to fight with the WD-40 to do ITS job.
WD_40 is great, but you need to remove it when you are done, so I do not bother. I use Oil to begin with and Tri-Flow to finish.