A Reliable Front End for Rubber Models

摘要

Prop drive systems that use set screws or solder in their make-up are subject to occasional failure. Here is a front end that features rubber motor tensioning, a motor aligner, and high speed free wheeler that is very reliable in that it uses no soldered joints or set screws in its design. For those modelers who may not be familiar with all of the aforementioned features, let us examine them, one by one. Rubber motor tensioning is desired when the motor length exceeds the distance from the prop hook to the rear motor peg, as most do. Tensioning keeps a long motor from unwinding completely so as to keep the mass, namely the weight, of the motor distributed more or less evenly between the prop hook and the rear peg (see "Longer Rubber Motors", Nov. 2004 FLYING MODELS). Doing this keeps the center of gravity from shifting during the glide phase of the model's flight. There are other ways of achieving this, such as braiding the motor. But, these other methods are not as flexible in adjustment at the field.