The geared extruder for your Ender 3
The PrimoDrop is a geared extruder that is based on the reliable 'Greg-Wade Extruder'. It was specifically designed to fit the Ender 3 3D printer and to increase its performance by adding the following features:
3:1 GEAR RATIO
PrimoDrop has a 3:1 gear ratio, which increases the torque of the extruder. This ensures that extruder does not skip a step, since it has enough torque to push the filament through the hotend.
Another advantage of a geared extruder is the increased resolution of the steps/mm value.
With the big gear (driven gear) it is possible to manually extrude filament.
THREADED HOBBED GEAR
The M5 bolt as a shaft keeps the design simple. It also centres and locks the threaded hobbed gear in place. A grub screw serves as an additional safety measure.
The hobbed gear is made from stainless steel and has sharp teeth that ensure a secure grip on the filament.
M5 sleeves centre the M5 bolt using bearings.
ADJUSTABLE SPRING TENSION
One of the main features that are missing on the standard Ender 3 extruder is a adjustable spring tension. Some Filaments (like flexibles) need less tension to be extruded consistently and other filaments that are more rigid (like PLA) need more tension. On the PrimoDrop extruder the tension of the spring can be adjusted using the knurled nut.
FILAMENT QUICK RELEASE
One of the main features that are missing on a standard 'Greg-Wade Extruder' is a filament quick release. This feature is incorporated in the standard Ender 3 extruder and is a convenient method of swapping out filament. The aim of the PrimoDrop extruder was to include this feature. By pushing on the top section of the idler the tension on the filament is released and the filament can be removed manually.