ORIGINAL: darock
Most Ringmasters I saw were from the Sterling kit and built heavy. They were sorta heavy for the wing area. The one detail that seemed to hurt their flying was the elevator movement. They often could deflect 90degrees. They didn't need much at all. A lot of beginners got into trouble by overcontrolling.
Excellent point! My S1 controls are set at minimum and provide about 20 degrees from neutral. For one already built, deflection can be controled by line spacing at the handle. Also make sure that bellcrank movement is not transmitting excessive force to the elevator and stab at full deflection (elevator fully deflected with more movement available at the bellcrank).
This may only apply to the S1 but make sure the joint for the wing halves is well done. This was a weak point in the old "cement" days and many wings folded in flight.
George