Katana Scabbard Fitting Instructions
When a Samurai sword becomes loose in its scabbard, the fit may be adjusted in the traditional manner as follows:
1/ Thoroughly degrease the throat of the scabbard to a depth of approximately 1 inch from the entrance. This can be easily done using cotton swabs and a solvent such as lighter fluid or paint thinner. Allow the solvent to completely evaporate. Do not allow the solvent to contact the lacquer finish on the outside of the scabbard.
2/ Take a section of wooden shim approximately one inch square from the shim in your Maintenance Kit (CAS reference OH1003). If you do not have a Maintenance Kit, a similarly sized piece of wood veneer (available in rolls from lumber yards or home stores) will work. Try this shim for fit in the top of the throat of the scabbard by pulling the sword about an inch out of the scabbard and placing the piece of shim on the habaki (the brass ferrule which butts against the guard). The piece of shim should be slightly narrower than the side of the habaki. Gently guide the shim into the throat of the scabbard while resheathing the sword. You will probably find that the fit is now sufficiently tight.
3/ Remove the sword and the piece of shim from the scabbard. Apply a light coating of glue (such as Elmers) to one side of the shim and replace it in the top of the throat of the scabbard, so that the shim is glued to the wood and the top of the shim follows the top of the throat. Make sure that the other side of the shim is dry and completely free from glue and that there is no excess glue elsewhere in the scabbard throat.
4/ Gently slide the sword into the sheath until a 1/8-inch gap is left between the top of the sheath and the guard, being careful not to move the shim.
5/ Allow the glue to dry and remove the sword. Make sure no excess glue is visible in the throat and then gently resheath the sword until it is fully seated.
6/ If the sword is still loose in the scabbard, repeat the same treatment on the other side of the throat (this is unlikely and the other side of the throat is more likely to be used for a second refitting if and when the sword fit becomes loose again).