Keeping this for reference only.. Not recommended. - Servo is too weak for reliable operation. Please see my Stepper Motor based revisions. (cross reference to be added when ready..)

Video :https://youtu.be/Lu2R_JStCFk

This is a small update to my original decoupler https://www.thingiverse.com/thing:1000218

It has a revised body and "decoupler plate". But the main change is that it now uses a single 0.2 x4mm x10mm spring for the spring force in place of the magnets used before.

As with the previous design, it will need careful sanding for smooth operation.

Make sure the servo operates smoothly with a servo tester during assembly and fitting, this is essential.

Bottom photo shows unit without SprongCover

Made to be assembled with 1.8mm screws.