A Custom Knife Progresses

The custom knife I've been making is coming along nicely. I heat treated the blade and did the initial sanding on it. Now comes the making of the handle and attaching it and a hand guard. The first photograph shows the blade after heat treating quenching, and tempering. I used a clay mixture of 1:1:1 of fire clay, #90 sand, and Pozzolana. I cast this mixture and let it cure for 3 to 4 days. A casting fixture is made from wood that is curved to give me a transformed zone of the desired shape. The clay is approximately 3/16ths of an inch thick where I wish the blade to undergo a slower cooling rate.

After Heat Treat

In the photo you can see a slight curvature induced into the blade due to this differential cooling. As I mentioned before the martensitic phase (body centered tetragonal, BCT phase) has a slightly higher volume, thus the curving. The blade after sanding to a 400 grit finish and giving it a first edge is shown in the next photograph.

The basic handle size selected is shown with the blade. I'll take a cast using air dry clay of the owner's hand to give a more ergonomic feel to the handle. This usually takes a few iterations of squeezing the clay to different compressions and letting it dry to give a satisfactory feel to the handle. I'll then shape the handle to match the cast version. This knife is a hidden tang knife so the handle will be the final feel of the knife. The hand guard will be hand shaped and decorated brass but I haven't decided on the handle material yet. I'm considering mother of pearl or polished bone.