Impeller Boat RC - spiral vase printable

Like the motor boat http://www.thingiverse.com/thing:272132 I wanted to make another bigger boat. So I just scaled up my boat http://www.thingiverse.com/thing:204303 to about 200%. Only the transom is half as thick.
It can be printed in two parts: 162,5 mm (aft) and 163,5 mm (bow) height.
Additional it has now a impeller drive and rudder control.
The complete rudder control unit can be taken from http://www.thingiverse.com/thing:272132
I tried to use my Roxxy BL-Outrunner which I already