Looking at your pictures I think you should forget about razors and continue making brushes. It's a very basic design but the metal cap gives it a little bit extra. Being able to turn both wood and metal will give you an edge over most woodworkers.

I do think your choice of a food safe wax finish was wrong. There's really no need for it to be food safe and I'm not sure if wax alone provides a good lasting protection against water. There are several ways you can finish a brush properly which should be easy enough to use next time you make a brush.