Whoo hoo! It's not bulls*** - removing broken taps
Who hasn't broken a tap off in the work? This time, the tapping was the last operation on a number of parts I made up for a job at work. Broke a tap below the surface - it was a 4-40 imbedded in a piece of 1/4" aluminum plate. Yeesh.
After a surprizingly difficult search, I located some alum (Aluminum Sulfate). Disolved some into water until the solution was basically saturated. Heated the whole thing up to "simmer" (not boil) and dropped the part in. Then I went and cleared the leaves from the yard and mowed the lawn. After about 4 hours of this, the only thing left of the tap was little undisolved parts that looked like pepper flakes. The aluminum was untouched. Woo hoo! I finished tapping the offending hole with a proper tap guide, and the part is perfect.
Thanks to the folks here. It may be old news to some, but it sounded hokey to me. After trying it, I can only say that it's like FM. (Freakin' Magic) The part (and my bacon) have been saved!
Science. If you don't understand it, don't talk to me about how it's going to end the world.