Penetrating Oils Compared

Posted by Alex Darmos on

Machinist’s workshop magazine ran a study, back in April of 2007, that compared the most widely used penetrating oils on the market, and the amount of torque it took to free rusted bolts after application. They ran the test by arranging a subjective test of the most popular penetrates, with the control being the torque that is required to remove the nut without oil. The results showed an actual significance in the amount of torque required, depending on the oil being used. The results are as follows:

Penetrating oil ….. Average load

None ………………… 516 pounds

WD-40 ……………… 238 pounds

PB Blaster …………..214 pounds

Liquid Wrench …… 127 pounds

Kano Kroil ………… 106 pounds

ATF-Acetone mix… 53 pounds

The ATF-Acetone mix, which was a “home brew” of a 50-50 mix of automatic transmission fluid and acetone, did better than any commercial product and only required 53 pounds of torque to remove the nut from a rusted environment. Another interesting find that came from this test is that Liquid Wrench did not take much more torque than Kano Kroil, which is surprising considering how much cheaper Liquid Wrench is. In conclusion, considering the tests are accurate, it’s safe to say that a home brew can be more reliable than the store bought oils.