It doesn't take hours.
First, never use an electric grinding wheel on something with an edge. The wheel spins too fast, and the steel gets too hot, and you lose temper, and edge-holding ability.
Yes, professionals use an electric wheel, but they are aware of what they are doing.
Second, the steel on a machete is normally fairly soft. A good Nicholson Black Diamond 12" bastard file will put an excellent edge on one in a very short time.
Then, if you want to really make it nice, get yourself a hockey puck
I have one of those (actually three - you can never have enough good stones) for my axes, but used one on the machete just to see the result. You can get one shaving-sharp.
Meddle not in the affairs of dragons, for thou art crunchy, and taste good with catsup - George of Lod, Year of Our Lord 297
I always take precautions.
Beware the Evil Bullet Fairies.