ER20 - Screw load is unusually high

A high screw load is caused by multiple extrusion factors, use the checklist below to quickly understand how to reduce the screw load.

The screw is approaching the maximum load and pressure it can handle. This means that it takes an unusually high amount of force to push the material through the barrel and out of the nozzle.

Determine the cause

A high screw load can be caused by a many different causes, but they all come down to the same thing: the polymer and/or objects (like additives) in the barrel are not liquid enough to overcome the pressure required to push out of the nozzle. Use the checklist below to verify your extrusion process.

1. Extrusion temperatures

The most common cause of this error is that the temperatures inside the barrel are simply too low, and the polymer too solid to be pushed through the barrel. Check the required extrusion temperatures needed for your material, and adjust the temperatures accordingly (but steadily) to see if the screw load reduces.

2. Extrusion speed

The most common extrusion speed is around 5 RPM (Rotations Per Minute). However, for certain experiments a higher screw speed is beneficial. If you are extruding at higher speeds,
of 10 RPM - 15 RPM it is recommended to lower the speed to reduce the screw load.

3. Nozzle diameter

The nozzle installed on the Filament Maker TWO can cause additional pressure or be fully clogged during your extrusion experiment. Visually inspect the nozzle and ensure it is not clogged. Alternatively, exchange the nozzle for a bigger diameter variant.

4. Transitioning

When transitioning between two materials, there is a higher chance of a high screw load due to the characteristics of both materials. This is especially true, when transitioning to a high temperature extrusion material, which has a lower viscosity level on it's relative temperature. Please always follow the purging guides closely when transitioning between materials.

5. The input and output

It's recommended to closely monitor both the input and the output of the Filament Maker TWO when extruding.

1. Does the output material meet expectations to the input material?
   If the material comes out extremely liquid, but the pressure is quite high, another factor might be in play.
2. Is the input material clean, free of debris, and the percentage of additives is acceptable?
   If the input material is contaminated, a foreign object is stuck, or the amount of additives is too high the screw might not be able to turn, despite the polymer having the correct viscosity.