I am now at the stage where I am satisfied with the basic shape and can move on to the heat treating.
Because it is so labour intensive and messy for just 2 tools I am going to send these out.
Basicially the technique is to wrap the steel then slowly bring it up to a temperature where the metal becomes ductile and the grain structure can be re aligned. It is held at a specific temperature for 1-3 hours then slowly cooled and quenched in hot oil to give the metal the hardness and ductility required.
I am trying for a RH of about 6200.
Heres a shot of the tools ready for the heat bath:
Here's a close up showing the shape of the tips: The more finishing I do now the less labour intensive it is after heat treatment.
Finally here is a close up showing the taper I ground into the steel to allow the tool to pass through the kerf as it penetrates into the depth of the wood without binding. I wanted a strong tool so I made the depth 1-1/4" and the back is 1/8". I don't want any chance of it bending in the cut at 300-500 rpm.