when you put the elastic bands on the dowels are you trying to get the rubber band around the 4 ends of the 2 dowels at the same time or are you just pulling over 2 ends of the 2 dowels at the same time. a newbie might try to go around all the dowels at the same time while some one experienced would not think of it. I have gotten by with 10 bands easily, just remeber to criss cross the last ones to hold the bads onto the dowels so they do not slide off. if tail heavy try to move the battery forward before putting dead weight on. this is not as important on a trainer but when you get into higher performance planes the weight makes performance suffer