It is often a desperate move scratch at something with your keys. At best you will tear up whatever you are trying to cut or pry, at worst you will break your key and be stranded. I've tried to make a keychain tool that could replace a small pocket knife or utility knife -- so I would think 'where are my keys?' instead of 'where are the scissors?'
The first half shows how to make a simple saw keychain. In the second half I do some more detailed grinding to make a knife-like tool that fits well in my finger tips.
Some key points:
- Sawzall blades are very tough metal
- Drilled hole with dremel grinder
- Shaped and cut with bench grinder
Here is a video of the final tool: