Jim, been there before with new small engines. Are you getting a good red glow on the plug with your igniter?? Does this engine have a muffler. Can you get to the exhaust for a prime. Does it fire on prime and then quit? Put a glove on to protect your fingers and sand those blades like Ray says. Are the carb bolts tight? Is the tank on your bench too far away for a good fuel draw?  I have a norvel .074 that will hardly ever start by hand but runs great after i get it going with a starter!!  Good luck in your trials.. keep "plugging away"  ..  I would be interested when you find the right combination, i doubt it is too much nitro i have used the Byron fuels in the past and they worked good.