What Can Cause the Ender 3 to Extrude Inconsistently? (Solved)

3D printing is a process where many things can go wrong due to the many components involved, whether it may be electronic, mechanical, or software, with each element bringing a distinct set of potential faults that can affect the printing process negatively.

Among all the issues you can face, problems related to extrusion are some of the most common ones, as there are way too many factors that can disrupt the sensitive process of consistently extruding the correct amount of plastic in the right positions.

Today, we will investigate the problem of the Ender 3 extruding filament inconsistently throughout the printing process, which creates a subpar final product by introducing plenty of issues ranging from weak adhesion between layers to poor surface quality and accuracy.

So, what can cause your Ender 3 to extrude filament inconsistently?

As there are plenty of distinct reasons that can cause your Ender 3 to extrude inconsistently, we have listed the most common ones that can cause the problem below:

  • The nozzle of your Ender 3 is partially clogged.
  • There are problems related to the extruder of your Ender 3.
  • The bed of your Ender 3 is not level.
  • The filament is not able to move freely through the Bowden tube.
  • The printer is unable to pull the filament due to external factors.
  • The filament has degraded due to reasons such as poor quality or moisture.

Next up, we will delve deeper into the reasons that can cause your Ender 3 to extrude inconsistently, find the appropriate solutions for all the possible reasons, and discuss how to identify the inconsistent extrusion problem as quickly as possible.

What Can Cause the Ender 3 to Extrude Inconsistently?

Inconsistent extrusion is a problem that will directly trouble the printing process and the final product you obtain from it while also being one that can be pretty challenging to isolate due to the many possible causes behind it.

Below, we have listed the potential culprits behind the Ender 3 inconsistent extrusion problem alongside their detailed descriptions, which we believe will help locate the root cause:

  • Partially clogged nozzle – A partially clogged nozzle is one of the first factors that come to mind for the issue of inconsistent extrusion, as the filament won’t have a clear path out of the nozzle due to the clogging introducing inconsistency.
  • Extruder problems – Practically speaking, an issue with any component of the extruder, such as the stepper motors, the stepper drivers, the gears, and the tensioner, can cause the filament to be extruded inconsistently, as the extruder is fully responsible for moving the filament down and out of the nozzle.
  • Printer bed not correctly leveled – A print bed that is not level will cause the gap between the nozzle and the build plate (or the print itself) to be miscalculated for some regions in the XY plane, creating areas where the filament won’t have enough room to come out of the nozzle.
  • The filament is unable to move through the PTFE tube – Similar to a partially clogged nozzle, a clogged or damaged (such as bent) PTFE tube will prevent the filament from moving consistently and smoothly, causing the problem of inconsistent extrusion.
  • External factors are stopping the filament from moving – External factors, such as the filament spool being tangled or being positioned at a spot that the Ender 3 cannot apply enough force to pull the filament, can stop the filament from moving smoothly and consistently.
  • Degraded or poor-quality filament – Poor-quality or degraded (such as water damage) filament can easily cause inconsistent extrusion by introducing instability to the process, as the filament itself needs to be homogenous for the extrusion to be consistent.

How to Fix the Ender 3 Inconsistent Extrusion Problem?

Fixing the inconsistent extrusion problem of your Ender 3 can be more challenging than solving most other errors due to the many factors involved, especially if you are unsure about what exactly is causing the issue in your case.

Below are the detailed solutions we recommend applying for the common reasons that can cause the Ender 3 inconsistent extrusion problem:

  • Thoroughly clean the nozzle of your Ender 3. We recommend attempting to clear the clogging with the help of a wire brush at first, followed by the cold pull method if the clogging is still there, and finally, removing the nozzle altogether and giving it a thorough cleaning as a last resort.
  • Maintain all the components of the extruder. Extruder maintenance is a long and arduous journey with many parts involved, which is why we recommend following the order of calibrating the extruder tension, cleaning and lubricating (or replacing, if necessary) the extruder gears, measuring the voltage values of the stepper driver, and finally, testing the extruder motor separately, which creates a path of tasks that increase in difficulty.
  • Correctly level the bed of your Ender 3. While adding an automatic bed leveling sensor to your Ender 3 is the best solution for consistent bed leveling, manual methods should also do the job as long as you are careful. As incorrect bed leveling is a widespread problem, we highly recommend double-checking.
  • Ensure that the PTFE tube is clean and undamaged. Even though inspecting the PTFE tube from the outside should be enough to see any possible issues in most cases, it wouldn’t hurt to remove, clean, and re-attach it to be safe.
  • Ensure that the filament spool is correctly positioned. You should always attach the filament spool to the spool holder on the top of your Ender 3, and the filament should have a clear path to the extruder without any tightness, tangling, or blockage. To test this, you can give the filament a light tug at the point where it connects to the extruder and see whether the filament spool spins freely.
  • Replace your old filament with a fresh spool of high-quality filament. Using a new spool of filament produced by a trusted manufacturer is the best way to remove any doubts about the filament itself being the problem, and in the case where the filament itself wasn’t the issue, you can always go back to finishing your old filament up as well.

How to Identify the Ender 3 Inconsistent Extrusion Issue?

While inconsistent extrusion is pretty easy to spot in more severe cases, slight bits of inconsistent extrusion may not always be easy to notice but still reduce the quality of your prints. 

The effects of inconsistent extrusion are best observed during the 3D printing process, especially during the printing of basic shapes, such as straight lines, as noticing flaws, such as dimensional inaccuracies, bumps, or lack of filament in certain areas, becomes incredibly easy in such cases.

Since the width of the extrusion is pretty small with a standard 0.4 mm nozzle, it’s definitely helpful to take a close and careful look during the print to be able to catch all the details, as observing the process from afar may hinder your ability to see the effects of inconsistent extrusion.

Wrapping Up

Facing the problem of inconsistent extrusion while printing with your Ender 3 is definitely not fun due to the damage it can cause to your prints, potentially rendering them unusable, while also being a problem that may take some time and effort to locate the cause of and apply the necessary solution.

A wide range of issues, such as a partially clogged nozzle, a malfunctioning extruder, a print bed that isn’t level, a damaged or blocked PTFE tube, a mispositioned filament spool, or a degraded spool of filament, can all contribute to the inconsistent extrusion problem for the Ender 3.

As fixing the problem will mainly be down to trial and error, we highly recommend taking your time with each step and carefully confirming that the problem cannot be occurring from a factor that you have already applied the necessary solution for, which will allow you to narrow the problem down with each applied fix.

Happy printing!