We've seen all of the Bruce Lee movies, we know and love our martial arts weapons in action, but what we don't realize is how dangerous these weapons can be if handled improperly. Without the proper training a weapon like the Nunchaku can really injure the user and a sharp edged sword or Sai can be even more damaging.
It is important to be careful with martial arts weapons and try not to see them as toys or play things to be casually used. Just because these martial arts weapons are no longer in service militarily does not mean they were not originally created in the name of war and designed to injure.
In order to avoid serious injury to yourself and to those around you it would be a wise decision to seek the proper training if you are interested in playing with martial arts weapons. Most martial arts classes out there today will have a dedicated group that helps students learn different weapons and will even present the ones who have proven worthy with certificates of merit.
It will probably take years to truly master some of the more challenging martial arts weapons. The tonfa, which are similar to night sticks, are one of the more challenging weapons to manipulate because they are designed to swivel in the wielders hand and strike using momentum. While learning this particular weapon it is common to lose control of the direction of the strike and accidentally smack your own arm or chest with the business end. You'll realize that accidentally striking yourself in such a manner is quite painful.
Any of the bladed weapons are risky to use if you are a novice with martial arts weapons. The sword, Sai, knife, or even the sickle can cause you and the people around you serious harm if you are not careful while using them.
When you first begin practicing with a sword you might want to try picking up a bokken. These are wooden practice swords that are designed to mimic the weight and feel of an actual blade. With bokken or bamboo swords you can even practice sword fighting with a partner without risking being cut. Another, but slightly less practical, method of practicing to use the sword would be to dull the blade severely. If the blade is not at all sharp it won't be a problem if you accidentally land it on your shoulder.
Martial arts weapons are a lot of fun but we must never forget that they are made with injury and death in mind. Be careful and get the proper training so that you won't hurt yourself.