How to attach a shaft to a rotary encoder?

What are the options to attach a shaft to a rotary encoder such as this : https://www.adafruit.com/products/377

My idea is to fix a cable to around a shaft, so as to have the shaft turn when the cable is pulled, but then I want to measure the rotation. That's why I'd like to attach the end of the encoder to the end of the shaft. 

Any ideas on this? I have to build the whole contraption from scratch.



The cheapest method is to use a piece of thick rubber tube, so your alignment doesn't have to be perfect. The best method is the type of joint Iceng points out - but they may be more expensive than the transducer
iceng3 years ago
Shaft encoders have excellent and strong bearings.
Enough so that the encoder is only needed to be stabilized against rotary movement on axis.

This style of shaft coupler permits small angular off axis mounting differences for
semi-permanent mounting.

There are many other kinds of off axis couplers if you want to peruse the subject.
bwrussell3 years ago
Attach it the same way the knob is attached. There should be a flat on the encoders shaft and a set screw in the knob. You tighten the set screw onto the flat. Drill a hole in the shaft, tap the hole for a small set screw and then tighten the set screw onto the flat on the encoders shaft.

Alternatively you could weld or JB weld the shafts together or use a good epoxy, particularly if there is plastic involved.