I don't stop at the flash though. I take off material until the prop is balanced to my liking. I've never heard that you're not supposed to take material from the hub until this thread. If it's common knowledge then it never made its way to me. In fact, until recently, I've never heard of anyone adding weight to a prop to balance it except by adding clear coat. I don't know how I came across it but a couple weeks ago I saw a video on YouTube I believe where a guy was adding tape strips to a prop for an electric to balance. Seemed like a good idea for electric motors but wouldn't work for glow as the fuel would dissolve the tape glue pretty quickly.