magnetized files

[J.W Younger]

I recently mail ordered some files and even tho they were different brands and types, they were all magnetized.
No problem too de-mangetize with a soldering gun just wondering if anyone else has seen this and what may have caused it

 

[mdavlee]

A lot of metal when machined will magnetize. It probably happens when they cut the teeth. How do you un magnetize with a soldering gun?