Making Handles for Japanese Handsaws

A while back I received a box full of old Japanese handsaws from a friend. They were in various states, with some coated with rust, some missing teeth, others were all gunked up with glue, and all needed to be sharpened. The box ended up sitting on my shelf for a while before I finally worked up the mood to start cleaning them and looking at them more closely. I tried both electrolysis and a store bought mild acid to get the rust off. In the end I ended up using the acid because it was faster than electrolysis and I had 8 saws in total that I wanted to get cleaned up.

Once I cleaned off the worst of the rust I sent the saws out for resharpening. My friends and I sent our saws as a group to Takijiro-san, a traditional saw blacksmith near Tokyo, for resharpening. Takijiro-san did an amazing job of tuning up the saws, and they were in beautiful condition when they returned to me.

With good saws in hand, it was time to make some handles. This was my first experience making handles and I’m certainly no expert, but everything went well and so far the new handles have been holding up.

Wood Selection

When I started looking around at my friend’s saws and the types of handles they had I noticed that almost all of them were made with either kiri 桐 (Paulownia), or some type of soft wood like sugi 杉 or similar lightweight cedar. To be honest I don’t fully understand the reasoning behind these two wood options being so prevalent, but one thing that my boss mentioned is that these soft woods can help to absorb sweat and keep your hand from slipping when using the saw.

In any case I figured I would follow tradition and use one of these woods for my new saw handles, and it just so happened that there was a small stash of kiri available in the shop. Decision made.

Fitting the Tang

The old school method of making handles involves using a solid piece of wood, drilling a pilot hole into the end where the tang goes, and using a long thin saw to cut the recess for the tang. I chose an easier method to make the handles using two pieces of wood, allowing me to use a trimmer to cut out a recess for each saw’s tang, and then glue up the two halves of the handle.

Below I have one half of a new handle with a recess routed out for the tang. You can see the pencil line where I traced around the saws tang to mark the actual size. When I routed I stayed within that line by a couple of millimeters. When the saw gets inserted the tang should be driven into a slightly narrower recess so that the wood fibers will compress around the tang, gripping and holding it in place. Kiri is notoriously soft so I left a generous amount of wood for compression, not knowing what the correct amount should be, and it all worked out in the end. I also planned to use heat when inserting the tang such that the perfect fit gets “burned-in”, but more on that in a bit.

Shaping the Handle

Below you can see the setup I used for shaping the handles using hand planes. After gluing the two halves of the handles together I layed out a series of reference lines to assist in shaping the handles into an octagon shape.

After shaping the octagon profile, I added a few more reference lines and kept planing to form the handle into an oval shape that felt comfortable to hold. I had fun trying to take some really thin shavings with a single blade mame-ganna 豆鉋 for the final surface, trying to make the handle as smooth as possible with no tearout.

Wrapping the Handle

Wrapping the handle can be done in a variety of ways, but it’s almost always done with some type of rattan. It’s quite common to see handles that are completely wrapped top to bottom with rattan. Cheap disposable blade saws often have this kind of wrapping, including many of my own. Another alternative that I have seen more so on higher quality saws is to leave the handle bare and only wrap the top end near the blade. The purpose of wrapping is to prevent the handle from splitting from the tension introduced by fitting the tang and through use.

I decided to wrap the handles with the second method, using a really thin rattan (somewhere around 1-1.5 mm diameter I think). Before wrapping I soaked the rattan in water to soften it, making it pliable and easy to work with. I also applied a bit of wood glue to the area I planned to wrap. Glue is perhaps not absolutely necessary but it does offer a lot of reassurance that the rattan won’t come loose and fall off overtime.

Below I’m about done with the wrap and am about to pull the end of the rattan back through, essentially hiding and locking the exposed end within the wrap itself. (There are lots of tutorials online for this method, including one variation by Mike Pekovich on Fine Woodworking.com). You can also see a bit of glue squeeze out, which I easily cleaned up with a damp rag.

Torching the Tang

Veggie kebab time!

I had a lot of fun with this step. I used a torch to heat the tang up to red hot and then inserted the blade into the handle. This is done to let the tang essentially burn itself into the overly snug handle, creating a perfect fit in the process. Even with the burning the grain still compresses quite a bit making for a really snug fit. The important part with torching the tang is to not let the heat flow up into the rest of the blade and ruin the temper of the steel. So the “traditional” trick that was recommended to me was to take a piece of zucchini and slide it onto the tang to act as a heat sink. I didn’t have a zucchini so I used a carrot instead.

Here you can see the blade burning the kiri handle as I started fitting the blade. I pushed the blade as far in as I could by hand and then finished driving the tang in with a wooden mallet.

When all was said and done I finished five new handles and installed them on the freshly sharpened saws.

The scorching on the saw below is how this saw came from the blacksmith. The carrot method really worked well, and I could hold the blade comfortably on one side of the carrot while the other side was red hot.

This turned out to be a pretty fun weekend project. If your saw handles get damaged or you just want to upgrade your saw with a custom handle, then it’s nice to have the ability to make a replacement. It’s also a great way to get old used saws in working order again.

-Jon