Ball Screw (customisable)

I needed to create a round corkscrew shape, which inturn lead to creating this ball screw model, the linear_extrude function in open scad creates a squashed thread and would not work for my purpose.

I've used the following setting in Ballscrew.scad to create the modles.

Screw 1 Right hand thread settings used:
F=50;// NUMBER OF FACETS
H=45;//HEIGHT OF THREAD
D=22.5;//DIAMETER OF BALL
DI=24.75;//DISTANCE AWAY FROM CENTER
A=360;//ANGLE OF TWIST USE NEGATIVE NUMBERS TO CREATE LEFTHAND THREAD
N=4;//NUMBER OF THREADS
SH = 80;//HEIGHT OF SCREW SHAFT
SD= 30;//DIAMETER OF SCREW SHAFT
CLEAN = true;//SHARP TRANSITION AT THE END OF THE THREAD WHEN THERE IS MORE SHAFT ABOVE

Screw 2 left hand thread settings used:

F=50;// NUMBER OF FACETS
H=45;//HEIGHT OF THREAD
D=22.5;//DIAMETER OF BALL
DI=24.75;//DISTANCE AWAY FROM CENTER
A=-360;//ANGLE OF TWIST USE NEGATIVE NUMBERS TO CREATE LEFTHAND THREAD
N=4;//NUMBER OF THREADS
SH = 80;//HEIGHT OF SCREW SHAFT
SD= 40;//DIAMETER OF S