You wanna know why the hardness of files and rasps produced by Pai Lu can be higher than 60HRC? Because we pay attention to two very important parts of all our file and rasps.
First part, the surface, if you have learned about the whole manufacturing process of files and rasps, you will know that,during quenching, there will be carbon emission, which will lead to lack of hardness of the surface. So a very important step will be took in our third working shop--to remove(polish) the surface which is lack of carbon. In this way, we keep the surface of our files and rasps as hard as the rest part .
Second part, tang part, it is the most fragile part of the file and rasps, so we have to do special heat treatment to this part to make it strong and hard. So now you know our secret!
- Pulling force: 30 kg or 50kg or requested
- Keep the handle as straight as the file and rasps themselves