I want to make a spade bit (aka a paddle bit), for a special project, and I'm wondering what kind of steel I should start with. Carbon steel, like 1045? Or 4140/4142? Or what? I have access to a heat-treating company, so I can have that process done after I've 'machined it' to the needed size/shape. I figure I'd start with a 1/4" or 5/16" thick flat bar about 6 - 8" long, cut part of it away to form the shaft and then grind three flat spots on it to register in my drill press. Then maybe grind the shape of the paddle end, making the pointed part and the two wings. Then grind the cutting edge on the two wings and the point, then have the whole thing heat treated. Am I on the right track with this process? Has anyone out there ever made a specialized spade bit? And what degree of heat treated do I need to go to?

Thanks in advance for any help...........

Walter