There was quite a bit of discussion in the comments area of the previous post about the merits and drawbacks of sending my knife out to be reshaped vs. doing it myself. Although I know that I need to be able to do it myself, this particular job got the best of me. In the discussions it became clear that I may have an unusual hangi toh. My knife has a double bevel**, a large flat bevel plus a small steeper bevel at the very edge of the knife. It was this second bevel that I couldn't reshape after I lost the point of the knife.
**ADDED 12 May 08: It turns out that Eli was correct in his comments on the previous post that my knife in fact does NOT have a secondary bevel. The difference in color toward the tip of the blade is actually the difference in the two types of steel that are laminated together in Japanese tools. This knife has one bevel. The good new is, that means I can sharpen it myself next time the point breaks!
The knife is back from the shop now and although it was apparent that they used a pretty coarse grit, I'm happy with the way it's performing. I've honed it more with my water stones and so far it's working great. I thought I'd show you how I'm using the hangi toh on the blocks for this Buddha print:
With the toh I outline all of the areas of the design that will print, removing thin slices of wood so that when I follow along afterwards with clearing tools there will be some space around all of the printing areas. While it would be theoretically possible to accomplish the same thing using a small u-gouge, I find that a u-gouge is not nearly as precise as a hangi toh. A u-gouge is pushed through the wood, compressing the wood fibers and tearing through them rather than cutting the fibers as the toh does. For a more free-form design and for expressive carving, u-gouges are great but this "map" design is tighter.
Here's how the block looks after some clearing has begun:
Some moku hanga artists use a flat bull-nose chisel to clear up against the wood that's been removed by the toh, but I like to use a u-gouge for that purpose.