Saya Repairs - A Short Study Of Mistakes

by Andy Watson

It happened. Then it happened again.

Lockdown during the COVID19 outbreak meant that like many other people, I was reduced to doing budo training at home and, as this started in the very early spring of 2020 when the weather was pretty awful, this meant training on the front room floor. It's not until you try training indoors that you realise how much room you use up when doing even relatively compact kata. So a couple of weeks in, while doing Ushiro, the end of my scabbard (the kojiri) hit the plant pot near where I was sitting at the moment of trying to complete the turn. My saya was jammed but my right hand and arm were intent on doing the draw. There was an audible crack and I realised that I had cracked open my koiguchi. I discarded this sword and went onto use "ahem" another person's sword that had been left at my house.

You would think that I would be smart enough to not repeat the same mistake but, sure enough, about three weeks later exactly the same thing happened. I now had two swords with broken saya. If we weren't in a lockdown condition then I would have asked my professional word-working friend to do the repair for me but naturally I couldn't do that and I decided that I would take up the process of doing proper saya repairs.

Jock Hopson Sensei had thankfully "donated" to me a whole ray skin (so called "samegawa" which I will write like this so it is not confused with the English word "same") quite some time ago, almost certainly when I had broken a different saya (I am quite good at this). Considering that I was going to be repairing Al Colebourn's saya as well though I decided that I should get in some practice first by trying to make a samegawa sleeve onto a bokuto. I found an old bokuto and started by marking out a narrow sleeve about 15mm wide around it. I then started using a combination of chisels, files and sandpaper to remove enough material that I could snugly fit a strip of samegawa around it so that it would be almost flush with the surface of the bokuto. It was at this point that I realised that I had not yet cut the strip of samegawa and attempted to do so with a pair of scissors. This turned out to be an error. The dimples on samegawa are basically bone and scissors are not the best instruments for cutting through bone. I therefore ended up with a strip of samekawa with not quite straight edges and a channel in the bokuto which wasn't exactly the same shape as the strip. I went ahead and used superglue to fix the samegawa in place. I did this in a couple of goes, first glueing one end in place ensuring that it was straight and waiting for that to dry. I then glued about 80% of the remaining skin and left a loose end. Once that had dried I did the final stretching gluing down using some tiny scraps to fill in the gap.

You can see from the image left where there are gaps and non-conformities between the edge of the samegawa and the channel. Al suggested to me that these gaps could be filled in by mixing some sawdust with wood glue so I did this by taping carefully around the samegawa and also on the bokuto so that only the edges were exposed. I mixed some sawdust and glue and carefully painted it into the gap. The end result was pretty good and a bit of sanding got rid of the excess glue.

I then moved onto painting the samegawa. I was advised by Jock to use model enamel paint and so this arrived with some artists brushes a few days later. I carefully painted the skin leaving wood covered up with tape (note to self, this enamel paint needs cleaning off with white spirit when cleaning the brushes). This took about three coats and then I got nervous about painting more on which was also a mistake as you will see later.

After the paint had dried over 24 hours I was then advised to file or sand down the dimples so that it would leave a nice flat surface. Being naturally cautious and worried that I would file the dimples down to the skin (which was possible given the fact that I had not painted it enough) I didn't quite file down enough and the surface was still slightly rough.

You can see from the image on the left that the surface looks pretty smooth without significant dips between the dimples. Unfortunately this still wasn't enough paint and filing.

You can see from the diagram on the left a bad example (above) and how this results in an uneven surface even after lacquering and (below) what a better job more painting would have on the surface.

I then proceeded to lacquer the outside and gave it about 4 coats. Although one can paint on quite a thick coat of lacquer, it really flattens down to a very thin layer when dried. You can see from the images below the final result.

So not a terrible job for a first try but I have identified several learning points which I will take care of as I go to do the actual saya repair...

  1. Cut the samegawa first with something strong enough to make straight edges (I now have some metal shears).

  2. Try to straighten up the edges of the samegawa once cut.

  3. Then mark out the channel on the saya.

  4. Remove enough material so that the samekawa skin is below the level of the surface and the dimples emerge above the surface.

  5. Spend a lot of time carefully removing the material so that the bottom of the channel matches the surface profile (new files and scrapers bought).

  6. Over the crack, form a metal insert and cut out more material so that it fits snugly. Ensure the samegawa goes over the top without protruding above the surface.

  7. Glue the insert in place and bind down tightly.

  8. Check the fitting of the samegawa and then glue in place with the join under the saya.

  9. Cut off any excess samegawa before gluing down completely.

  10. If necessary, glue scraps of samegawa into any gaps (once painted, filed and lacquered, any joints won't show).

  11. Remove any covering and ensure that the fitting of the samegawa is perfect.

  12. Recover the saya with protective tape and paint with enough coats so that the dimples are almost invisible (this might be 6-10 coats).

  13. Carefully file down so that the samegawa is level with the surface. Finish with very fine file and sand paper. Polish with an abrasive to get a really shiny coat.

  14. Lacquer about 5 coats so that the surface is perfect.