Cleaning Your Saya
by Jim Kurrasch
I have a new blade (to me) that was picking up some staining near the mune. So it inspired me to clean the saya. I figured that I should mention the process, in case someone else has a similar problem. And I am sure that some of you do. Since I was doing this I figured that I would check my better blades, and 3 of 5 needed saya cleaning. One of my friends has commercially made saya of American wood for 20+ years. They are nice and I use them. But he glues them together so they will never come apart. That is fine also since as he feels if they need cleaning, they should just be replaced.
But the fine old saya are a thing of beauty, and frequently should be saved. Especially the ones with the ivory hato-mei – pigeon eyes, and horn saya guchi (these tend to hint that they hold a important blade). Or they may have a saya-gaki that has some importance. They just add something to a fine blade. Do not expect the dealers to share this opinion on your saya, since they will make money by you having a new saya made.
What does one look for. Well the worst thing is staining, or a spider-web rust starting in a area. Other things would be a scratch or rubbing of a area of the blade.
Then what does one do? Well, first open the saya. I used a long handle screw driver that barely fit into the saya. I put it in as far as it would go and gently twisted. If it did not start to crack at the seams fairly easily I moved to another area. Once the cracking started, I move the screwdriver slightly and twisted again.
Once opened, match the stained or rubbed part of the blade to the saya . Near the stained area you will probably find a dark – blackish area, that must be removed, since it is probably the cause of your stain. Near the rubbed areas there may only be a high spot. To remove or lower these areas use a knife, blade or scrapper, and simply scrap out the spot.
Never use sandpaper on the inside of your saya, since it will leave grit, that will scratch your blade. The Japanese traditionally used the outside of a rush plant that was very coarse, to smooth the outside of the saya. But the insides were cut out. You do not have to cut very deep, only remove the offending spots. You will also notice some dings where the screw-driver pushed against the saya. Since these are on the inside they will not be noticeable when the saya is glued back together. But they may be high spots. So check them and remove what is necessary.
After cleaning the saya it is time to reassemble it again. clean the areas to be glued by light scraping. Apply a thin coating of white glue to the outside edges of the bonding areas (avoid areas near where the blade will be). Put the saya together, and hold it in place with rubber bands. Clean off the glue from the outside of the saya with a cloth. Check the inside of the saya for any excess glue, and clean it up. And let dry overnight. Do Not have the blade in the saya at this time.
The next day remove the rubberbands. Clean the glue from the outside of the saya with a damp rag. Look inside the saya for any problems. Let the dampened areas of the saya dry. And gently replace the blade. For a couple of weeks after this be aware that you did some work and look for any additional problems. Just take your time, and be aware of problems, you will save enough money by doing the job yourself. Also it might help to have a generous amount of chôji oil on your blade for a while.
And for lacquered saya that you do not want to open? Once in a sword shop in Japan I noticed them cleaning the inside of a saya with a triangular wood rasp, welded to a long rod. Check where the problem spot is on the blade. Hold the rod a similar distance, and work the area about where the spot is (ha or mune). The rasp should be fairly fine, and shaped triangular with 1 short side and 2 long sides. Or sometimes one can find a file that actually has a knife shape. If one does this often it would be a fairly good idea to build up a supply of long handled files, and see what works best where. And remember to empty out the saya prior to putting the blade back in it.