5 Ways How to Fix Inconsistent Extrusion & Lines in 3D Prints

You’ve got everything set up as usual and it’s time to get your 3D printer extruding away, which goes just fine. After some time, you notice, the print quality isn’t up to par.

This could be due to inconsistent extrusion in your 3D printer, which has many possible causes behind it.

This article will attempt to list those causes and give you a quick guide on how to fix the issue with some step-by-step solutions.

Why is My 3D Printer Giving Inconsistent Extrusion?

If you are printing something and you want it to look good and should be of high quality then perfect extrusion is essential.

If your printer does not extrude the filament consistently it will affect your design and will ruin the resulting print.

Inconsistent extrusion is a problem that can occur due to many reasons such as extruder problems, nozzle problems, or even an improper setting can cause it

It is considered as one of the many common problems that a user faces in 3D printing which is definitely fixable if you do the right things, which will be described in this article.

You should keep an eye on the printing process and if you notice that the print is bumpy or the size of the print layer is varying, it means that your nozzle is extruding inconsistently.

Here are the major causes behind the problem of inconsistent extrusion. Find out the actual reason that is causing the problem and then proceed forward to pick the best suitable solution.

Printing at Low Temperature
Nozzle is Clogged
Short Z Distance
PTFE Tube is Clogged or Have Resistance
Using Bad Quality Filament

How to Fix Inconsistent Extrusion & Lines in 3D Prints

The solutions behind fixing inconsistent extrusion and lines are fairly simple so follow along to get this issue solved once and for all.

If you are experiencing inconsistent extrusion, it’s because your filament won’t extrude smoothly enough to create a high quality model.

To enjoy a perfect experience and to get the best from the 3D printer, make sure that the nozzle is extruding efficiently.

Below are the main solutions that are effective in solving problems of inconsistent extrusion.

1. Increase Your Printing Temperature

If you are facing this problem, the first thing you should try is to increase the temperature. It is possible that the filament is not getting enough heat to get melted properly.

Increase your printing temperature and make sure that the filament is melting completely.
Try to decrease the speed and check if any improvements occur so filament has enough time to heat up.
Make sure that you find an optimal temperature because too much heat can also cause other problems such as oozing and stringing.

2. Make Sure the Nozzle is Not Clogged

Sometimes residue from the printing process and from burnt filament are left behind in the nozzle and get stuck. This causes the nozzle to become partially or fully clogged.

Check the filament being extruded from the nozzle during the printing process and see whether the filament is coming out straight or curled.

If the filament is extruding curly it means that the nozzle is probably partially clogged and if the filament is not even coming out from the nozzle, it is the indication of a fully clogged nozzle.

Sometimes you can get rid of clogs by just increasing the printing temperature and extruding filament out
If the clog or jam is quite stubborn, make use of a nozzle cleaning needle to push the residue out
The best way to really clear your nozzle is to do hot and cold pulls, also called atomic pulls
You can use cleaning filament to extrude through your nozzle which does a great job of clearing out clogs.

3. Make Sure That the Nozzle is at a Good Height

The Z distance can also be a great reason to cause inconsistent extrusion and lines in 3D prints. If the extruder is not making any noises and printing a very thin layer, it is a sure indication of improper nozzle height.

This is due to the fact that when the nozzle is too close to the print bed, the filament will not have the required space to extrude perfectly and will lead to inconsistent extrusion.

Make sure that you are using a good layer height that is providing enough space for the filament to extrude from the nozzle.
Increase the layer height step by step and check if any improvement occurs.

4. Check the PTFE Tube

Many people end up missing this factor out, which is checking the PTFE tube, but it can definitely be a contributing factor towards your inconsistent extrusion.

If your PTFE tube has experienced heat damage on the hotend side of things, then it can cause blockages in the extrusion pathway. The stock PTFE tube that usually comes with a 3D printer isn’t the best quality.

Check that your tubing is fitted on properly and isn’t damaged
Get Capricorn PTFE tubing which has a higher heat-resistance and smoother grip on filament

5. Use a Filament of High Quality

The problem might just be the quality of filament that you purchased. 3D printer filament manufacturers have been getting a lot better in their tolerances and quality control, but you can still get some pretty poorly made filament.

These low quality filament are ones that have inconsistent diameters throughout the spool of filament. When the filament is melted and extruded, there is going to be a change in flow rate which can lead to inconsistent extrusion and lines throughout the print.

Also, using bad quality filament that includes extra additives and such materials makes it difficult for the melted plastic to extrude from the nozzle without being disturbed.

If you are using an old filament then the probability of problem occurrence increases because the filament absorbs moisture from the air and loses its quality with the passage of time.

Make sure that your filament is protected in an airtight box to prevent moisture absorption.
Try to dry out the filament if you think that there is moisture in it which is causing the problem.
If you are still facing the problem it is recommended to replace the old filament with a new filament of high quality which is being opened for the first time.