Here's an example of a razor blade balancer I made back in the fifties took about five minutes, worked fine. I also might add I generally only balance my props for the high performance competition engines (that generally turn over 20 thousand static.

Another trick I sometimes do that does have an effect is if I have a prop with a known heavy blade its marked and mounted with the heavy blade opposite of the piston at top dead center. I don,t beleve any of our engines acheve perfect 100% balance due to crankcase room considerations.

John