Best encoder for nema 17 motors

[jimmy]

Hello to everybody,
i am new here, just registered. We are building a medium/big size 3D printer and would like to have encoders on XY axis. We are using Nema 17 stepper motor, what would be a good encoder to add? I read on the docs that only quadrature encoders ae supported at the moment or something changed? Any suggestio would be much appreciated.

[JohnHaine]

Hello to everybody,
...I read on the docs that only quadrature encoders ae supported at the moment or something changed? Any suggestio would be much appreciated.

Supported by what? Encoders are quadrature almost by definition if you want to know the direction as well as magnitude of movement.

What do you want to achieve? Are you trying to make sure the motors work better and you avoid missing steps? If so you can get "stepper-servo" motors and drivers (nowadays the driver often built in to the motor) which you control by sending pulses just like a stepper, so the printer controller doesn't need to know the motor type.

If you want to measure and control the actual print head position there are very good lowish-cost magnetic linear encoders around, a good supplier is https://www.machine-dro.co.uk/ - I used one for my big mill and it's excellent. However to be of much use you'd need to have a controller that can accept the quadrature signals from the encoder, I have no idea if these exist for 3DP - they are certainly not common for low cost CNC.