Adafruit Aluminum Flex Shaft Coupler - 5mm to 10mm

Connect this to that with a set-screw coupler. These couplers are made of machined aluminum and have a spiral cut that makes them slightly flexible, so they can fit two shafts even if they are not perfectly co-linear, reducing binding effects.

The way they're cut makes them a little springy in the X, Y, and Z linear axis, but not in the rotational axis. This means you won't experience increased backlash, making them suitable for precision CNC work.

This coupler will connect a 5mm diameter shaft to a 10mm diameter shaft. It's a perfect add-on for stepper motors, providing secure attachment with two sets of double set-screws on each side. Use a 2mm allen wrench to tighten or loosen the set-screws.