A dull shovel is an additional labor cost. That is why many people try to sharpen it with improvised means.
Most often, a file or grinder is used for this purpose, but they do not help for long.
There is an old-fashioned method that will help you deal with this problem faster.
Using a file does not give an effective result, and a grinder shortens the bayonet significantly.
This method was used by blacksmiths who created real masterpieces from metal - it is called work hardening.
We will use an anvil and a hammer, with which we simply beat off the dull edge. In the field, we use a regular stone as a base.
A few hammer blows and the edge of the shovel became sharp again. The most interesting thing is that after such treatment the bayonet becomes dull more slowly.
You should only hit the edge of the metal with the flat part of the hammer. Do not heat the bayonet. Also, do not use excessive force, as this can dent the shovel.