If you don’t have the right tools, or a steady hand I would first and foremost recommend that you leave the shaping of any machete blades to a sharpening professional (most knife shops have a sharpening service). However, if you have a steady hand and a good grinder, putting a sharp edge on the machete is straight forward albeit time consuming task.



If you are going to sharpen the blade yourself the first thing you need to determine is how sharp you want the blade to be. It might seem obvious that an ultra sharp edge might seem like they way to go, but remember the sharper the edge, the quicker it dulls. Since I tend to use my machetes more for blunt force task, rather than precious cutting ones I typically have a steep kinda dull edge that rarely if ever needs sharpening.



To create that edge I start by taking a brightly colored marker and mark in about 1/8in on each side of the blade all the way down its length. Then after securely clamping the blade down I take my grinder and grind at an angle that will grind from the inside edge of the marked line to the center of the blade edge. Make sure to take several grinding passes to reach this angle (about 10 to 15+) rather than trying to grind it all off at once. If you grind correctly on both sides (it takes some trial and error), then the marked line will disappear, and each side will meet in the middle of the blade. I typically find it helpful to split the curved section of the blade, and the flat section of the blade into two different sharpening zones, which is to say that I will take a few grinding passes at the curved section than take and equal number of passes on the straight section.



Now 1/8in back is what I use for creating a dullish blade, so if you decide you want a sharper blade start by marking further back (.25in for regular sharp and .375in for ultra sharp), and then grind at a the subsequent shallower angle. Also when creating sharper edges I find it helpful to run the blade thought a knife sharpener when I am finished grinding (http://www.harborfreight.com/handheld-knife-sharpener-94620.html).