Extruder spring insert/spacer

This is an insert for extruder's spring. It can be placed on both ends and provides a centering point for the screw. Additionally it has a 1mm spacer/brim at the end for the spring to sit on and compresses the spring thus making it stiffer. The main reason for creating this was to eliminate a screeching sound coming from the spring touching directly on the aluminum body of the upgraded extruder. As a side note I kept the original extruder spring as the aftermarket one was way stiffer and with the additional spacers on both ends became excessively stiff.