Wltoys a959 / a969 / a979 Improve Steering Angle, Fix toe-out angle and 12 degree caster angle with 3d Printed Parts

This is a set of files for improving the steering angle of the Wltoys a979 (also for a959 and a969).

This model's steering system articulation is way too low and the wheels may only turn 10-15 degrees most which causes the turning radius to be too much on low speeds. With the new design the wheels may turn upto 25-30 degrees.

I have seen some alternative designs but they tend to end up with longer steering arms. Tip of the arms were further at the front which would cause losing the Ackerman geometry. This design keeps the steering arm tips next to the steering buckle ballhead thus preserves the geometry.

Changed parts are C-hubs, steering arms, part of servo saver, steering rods and servo rod. Rods are printed with TPU. Other parts printed with PLA.

New design also removes the excessive toe-out angle of the front wheels.

No additional hardware is needed. 

All parts can be printed without support. Use 3.2mm wall thickness (Actually wall thickness setting makes the parts totally solid)

Update 20/06/2022: 1mm longer 33.5mm long steering rod added.

Update 27/12/2023:

• Included latest setup in a new folder.
• Changed C-hub to a design with 12 degree caster angle.  (A mirrored copy of this part is needed for the left side.)
• Changed right steering arm.
• Omitted 3d printed servo arm and used the stock servo saver arm.
• Used 31,5mm hole to hole distance on right and left rods.
• Used 28,5mm hole to hole distance on servo connection rod.