This is a paddle shifter system for 280 mm and larger diameter steering wheels with 70 mm bolt mounting pattern. This design can be built with only shifters or shifters + buttons, wired or wireless via BT.

The complete shifter consists of two shifter assemblies and a base plate. The shifter unit and paddle hinge should be 3D printed. Paddle and steering wheel mount plate can be printed, but I recommend laser cutting or CNC milling for maximum rigidity.

The shifter has a nice and well defined click. It is magnetically returned, and it uses a micro switch. It mounts to the back side of any steering wheel with standard 70 mm bolt pattern.

YouTube video showing paddle shifter operation: https://www.youtube.com/watch?v=Pz5LogKsN7o

BOM:

• Printed / laser / cnc-cut parts
• 4x 8mm dia, 5mm tall neodymium magnet
• 2x KW10 long r shaped lever micro switches (from ebay, 13 x 6 mm footprint)
• 10 mm M3 mounting hardware for paddle, shifter base mount and end-of-travel stop
• 28 mm M3 mounting hardware for shifter units
• 3 mm rod for paddle hinge
• Some hot glue, epoxy or CA-glue

Notes: The parts are not in optimal print orientation. Rotate them before printing. Some nut holes are closed with 0,2 mm thick extrude to improve print quality, use a small drill or a file to open them after printing. The shifter paddle in real world pictures is different from the one that is available for download.

Update 1: Added a shifter mount plate with buttons. It accepts buttons with 12 mm mounting hole diameter. I used buttons with 16 mm housing outer diameter.

Update 2: Added shifter mount plate /w buttons version 2. The buttons are arranged further away from wheel center. This version also comes as a variant, that has mounting holes for wireless hardware & two status indicator leds

Update 3: Added wireless instructions, wireless base station enclosure and F1 style paddles

Update 4: Added a stronger paddle hinge to fix the small flex in the paddle. Print hinge with high infill. PLA, PETT or PETG recommended.