this was our first test of the cylindrical balloon, using five candles.  although it did not try to take off it did seem to become somewhat more buoyant.  for the approximate size of this balloon one of our sources suggests a minimum of seven candles, today i designed a setup with nine candles since five did not produce enough lift however it also did not produce any singing on the paper.  one thing that i believe would be helpful is if we had an effective way to preheat the balloon before relying on the candles as a heat source.