A Tumble Turn is a Feather Finish with a bonus step (sort of).
Start backing DC, dance the three steps of a Feather Finish RLR with 1/2 turn to end on RF facing DC. Continue to rise over the course of the three steps. Because step 3 is continuing through both rise and rotation, the step will not be as big as it is in a normal feather finish.
The "bonus" step is a reverse pivot. Continuing to curve leftward, step forward LF towards center. As you step onto the reverse pivot, drop your weight onto the LF and flex left knee, turning through the pivot to back LOD. Follow with any figure which can follow 1-3 Reverse Turn.
Amount of turn for man: Commence to turn L on 1, 3/8 between 1-2 (body turns less), 1/8 between 2-3, 1/8 between 3-4, 1/4 on RF on 4.
Amount of turn for lady: Commence to turn L on 1, 1/4 between 1-2, 1/4 between 2-3, 1/8 between 3-4, 1/4 on LF on 4.
Sway: SRRL for man, SLLR for lady. To complement the rightward sway, the man can turn his head slightly rightward on 2-3. He should turn his head strongly to the left on 4. The lady should keep her head to the left on 1-3, but can turn it open to the right on 4.
Rise & Fall: Begin to rise on end of 1 (NFR for man), continue to rise 2 and 3, up on 4, lower at end of 4. Well, that's how the tech book would describe it, anyway. In reality, you'll probably reach the peak of the rise right in between 3 and 4, and lower as soon as your weight hits the 4.
Have fun tumbling!
Sincerely,
Jonathan Atkinson
www.ballroomdancers.com