Functional Swords
For most people viewing this site, information on a functional "cutter" sword is probably what you're looking for.
A functional sword (or "practical" sword) is a sword that is designed to withstand the force of cutting soft and hard objects. Not to be confused with decorative swords, or practice swords. Decorative swords are for decoration display only. Practice swords are for practicing kata without the danger of a sharp edge.
There are three general categories for functional swords:
- Light cutting: beach mats, pool noodles, water bottles, etc
- Medium cutting: regular cutting of light targets and occasional cutting of tatami omote
- Heavy cutting: regular cutting of Tatami Omote and occasional cutting of heavy targets such as 3"+ bamboo, multiple rolls of tatami omote, or mats wrapped around an oak dowel
A good functional sword also has these characteristics:
- The sword is heat forged. This means that the steel has been heated and pounded into shape. If the sword has also been folded in the process, this is even better. (click here for more on Japanese sword making).
- The sword should be made of high-carbon steel. Low-carbon steel is still better than nothing, but the higher the carbon count, the better. Avoid swords made out of stainless steel or aluminum. These may be ok for decorative or practice swords, but are not designed for cutting. Just because a sword is made of metal and it sharp doesn't mean it can stand up to the rigors of multiple cuts.
- The sword has a full tang. The tang is the portion of steel that extends inside the handle (tsuka). A "full" tang extends all the way through the handle. If it doesn't, the sword can break or the blade can come loose: either is a dangerous situation. For functional swords, a full tang is a must.
- There are no loose fixtures. The hand guard (tsuba), collar, and handle should all feel very tight and solid. Loose, or rattling fixtures could be a sign that the blade is coming loose. The fixtures are generally just wedged into place, so if you find some rattling pieces, it may just need a firm adjustment.
- The sword should fit snuggly, but not tightly, inside its scabbard (saya). It shouldn't fall out when tipped upside down, but should be easy enough to pull it out without much effort.