I've been doing traditional Japanese tantos for about 15 years. Although tim consuming, they are very rewarding to build. I typically start with a mix of 1050 and 1095 or similar steels. I stack, forge-weld, draw, restack, etc, building these up to 800-1200 layers. Depending on the syle of blade, I may have lower carbon mixes of steel welded to the spine or sides san-mai fasion. I've done a wide variety of blade styles, even using home-smelted iron in the mix. Once shaped, I use a mix of clays and water quenching to manipulate the curvature (sori) and hamon of the blade.