Having never made a wa handle before, I set out to learn as much as I could. I found some excellent videos on YouTube. Wa handles are typically octagon (sometimes hexagon) or round. A ferrule is attached to a handle and then the whole thing would be drilled or burned to accept the tang of the knife. Rarely I see pins, but they do appear occasionally.

The traditional wa handle would have a ferrule of horn. As my horn supply is low, I am opting for ebony instead. Looking through my blocks I decided the colour contrast of ebony and maple burl would make for a warm handle. For a separating layer I have some 0.065" brass stock. I cut about 1-1/4" off of a block of ebony and trim to an approximate cube with the band saw. I cut 3-3/4" of maple burl and a 1-1/4 square piece of 1/16" brass.. Together they look like this. Mark each piece for center and dill. First pilot drilling with a small bit, 1/8" or smaller. This should be no larger than the knife thickness at the neck. Pilot through the centres of all the pieces. To check the faces for surface contact. I used a piece of 1/8" dowel. Here I am checking the big dowel's diameter. I am using some poplar for this. The dowel size is to be the same size as the widest part of the tang, in this case a 7/16" dowel is used. Once the pieces are lined up, trace the tang outline. This will indicate how deep we need to drill in the maple block Drill the pilot holes out to 7/16" or whatever size dowel you are using. There will be some glue going into the hole, so a little loose is better than pound-on tight. Using the drill press, drill into the handle block just past the required depth to accommodate the tang as outlined above. Insert the dowel and mark for cutting. Cut dowel. I am adding some holes for epoxy to stay in. This gives some room for extra epoxy and increases the surface area. For this build I used Permatex 84107 . There are a lot of high strength epoxies, Gorilla, Acraglas, West Systems etc. will work fine. Goop epoxy in the hole and on the dowel, gently work it in by rotating the dowel. Some will flow out of course. This is will be used to glue the brass spacer on. With the brass spacer on apply more epoxy on top. Goop some more inside the ferrule and press everything together. You want excess to squeeze out. For clamping, I end clamped with about 50 lbs force. I used a key ring so I could clamp over the dowel. Let this set up for an hour or so.

Another approach preferred by some is to not drill the ferrule all the way through. This would hide the dowel and present a very clean ferrule front. If you do it this way, you'll want to make sure that your dowel is a little shorter and when compressing you can squeeze everything tightly together and not bottom out the dowel. Leave about 1/8" extra room for epoxy and you'll be fine.
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