There are many different ways to modify a machete.
By using different grinds on various parts of the blade, you can maximize the utility of your machete.
Most commonly, the blade is divided into two parts:
The upper chopping part of the blade is given a convex, rounded grind with a machete file to give it a durable edge that resists lodging in the material you are chopping.
A finer, sharper edge is given to the lower half of the blade, which is not subjected to the same forces when swung, and can be used for fine cutting or whittling. This edge can also be established with the mill file, which is fine for most work situations.
If looking for a razor edge, a finishing stone can be used.
As with most things, everyone has their own way of doing things. Here are some great videos that demonstrate how a machete can be modified.
This video shows 4-5 different useful edges that can be placed on a machete. Find the 12 inch Ontario machete he uses here.
Here is another modification in two parts. See our line of Tramontina machetes from Brazil.