Making a TWIN RC Wankel Rotary Engine - The Crankshaft (Eccentric Shaft)

Ever since I made the video with the starter modification on my O.S Wankel engine, I wanted to make a multiple rotor assembly. Last year, I found a second one, new on ebay and I didn’t lose the chance to buy it. I know many of you will ask me why not a 3 or a 4 rotor engine? It would be absolutely crazy and beautiful, but the cost is really high (almost a grand each) and the complexity is much higher for my skills. We’ll start with the 2 rotor and if it works we can dream. Making this crankshaft was quite the task, because due to it’s thickness, when the diameter started decreasing on machining, it kept bending slighlty. I was constantly checking with the dial indicator, and the best I could do was to finish the part with runout. I could have used a steady rest, but I don’t have one at the moment. Also one of my concerns is that I won’t heat treat it as it would bent to the point that it’d be unusable. Heat treating is not an option for me unless there is some secret I don’t