There have been plenty of times when I see lines on the side of my 3D prints that don’t look too great in terms of quality. I set out to find the best ways to get rid of these 3D print lines so my prints can look their best.
3D printing has many parameters, settings, mechanical parts which does make it quite the task to narrow down fixing a specific problem.
To get rid of 3D print lines, you should optimize your printing temperature and slicer settings, as well as check and replace the necessary mechanical parts on your 3D printer. Using a stable print surface and making sure your bed is correctly leveled does help. You should also use high quality filament for 3D prints.
Keep reading this article to find out the details behind the solution.
Why Are There 3D Print Lines on the Side of my Prints?
The sides of the 3D printed parts consist of hundreds of individual layers. If your printer is working properly and the printing process has no issue, then you will see a smooth and single surface.
But if there is something wrong, even with a single layer in the printed model, you will be able to see it even with the naked eye.
These improper layers then start to look like lines or ridges on the sides where they are appearing. I will be telling you some of the reasons which are becoming the cause of these lines on the side of your print.
The list of some main causes of these 3D print lines is as follows:
- Temperature too High
- Abrupt Temperature Changes
- Mechanical Problems
- Damaged Extruder Nozzle
- Printing too Quickly
- Unstable Print Surface
- Bad Filament Diameter Quality
How to Fix Lines on the Side of My 3D Prints
In this section, you will be getting all the solutions to fix the above problems, which are causing lines to appear on your 3D prints so, keep reading.
1. Temperature too High
If the temperature is higher than the usual value, it makes the plastic melt more, which allows plastic to extrude more freely, with less control.
Printing at higher temperatures usually gives the layer better adhesion, but at the same time, it becomes the cause of many other issues such as blobbing and oozing.
The higher temperature affects the layers and causes lines on the sides of printed parts.
To fix this I would advise to:
- Aim to print at a lower temperature, start low and build your way up
- If you are getting under extrusion under such circumstances, slightly increase your temperature
- It may take a few test prints, but once you find your optimal temperature, then you should get better print quality.
2. Abrupt Temperature Changes
Most of the 3D printers present in the market are using a PID controller that helps in regulating the temperature of the extruder. If the PID controller is not tuned properly, you may have fluctuations over time.
These fluctuations in the temperature make the filament hot or cold and disrupt the printing process. This disruption can cause the layers to extrude differently, creating ridges on the sides of your print.
- Make sure your PID controller is tuned properly to keep the temperature tuned at all times
- The temperature variation should be as little as ±2°C
- Use a brass nozzle for better thermal conductivity to avoid abrupt fluctuations
3. Mechanical Problems
There comes this term known as Z-banding, which is one of the causes of why you experience horizontal lines over the outer shell. You will see these patterns repetitively after every few layers.
- Bent Lead Screw
This is one of the most common causes of Z-banding because this lead screw can become bend and can cause weird patterns to appear on the surface.
If you remove your lead screw and try rolling it on a flat surface, you can see whether it is bent. If it is bent, at certain layer heights, you’re going to get movement which negatively affects print quality, which can lead to those lines in the side of your print.
Make sure you don’t secure the top of the lead screw because it can exacerbate the problem. The best place to secure the lead screw is at the bottom and in the middle.
If your lead screw is bent quite significantly, you should probably look to get a high quality replacement.
- Rod Maintenance Needed
If the rod after continuous use is wearing down, it will disturb the functioning of the z-axis.
This will affect the proper printing pattern. You can use lubricant for the rod to help it move smoothly over the surface.
- Belt and Wheel Adjustments
You need to adjust the belt and wheels of the print because if they are not properly fixed, you will see weird lines on the sides and surface of the print.
- Linear Bearings
Having slow in the linear bearings is another common mechanical problem which will lead to Z-wobble and possible give imperfections such as lines on the side of your print.
4. Over Extrusion
The excessive filament coming out of the nozzle during the printing process starts depositing on the layers, making the layers look thicker.
These thick layers actually make the nozzle touch them, which starts causing the lines to appear.
Another problem with over extrusion is that it has a high flow rate, which is causing more filament to come out. This makes the layers uneven, and uneven lines can be seen on it. What you need to do is simple:
- Lower the flow rate of filament coming out of the nozzle
- Reduce the temperature of the extruder to avoid the extra melting of filament
5. Damaged Extruder Nozzle
Now, this is a problem where over time, the nozzle can wear out either due to general wear-and-tear or printing with abrasive filament.
One of the reasons is that it is too close to the bed that it scrapes the tip-off, and the other is that you might have scraped it off while cleaning it.
The solution to this issue is simple:
- You need to replace the nozzle with a newer, high quality one
- Test printing temperatures and print quality after replacing the nozzle
- If you are printing with abrasive filament, get yourself a hardened steel nozzle
6. Printing too Quickly
Now, what happens is that when the extruder is moving at high speed, it can start to deposit excess filament on the sides of the print.
You will be able to notice such lines patterns at the curved sides, and it is also visible on the flat surface.
Doing the following should help:
- Lower the printing speed
- This will give time to layers to adhere properly, and less filament will deposit on the sides.
- Start lowering the printing speed in intervals of 5-10mm/s.
- You can check your advanced printing speed from the slicer settings to change certain parameters.
7. Unstable Print Surface
These can be two surfaces; it could be either the printing bed or the place where you have placed your printer.
As this printing is all about precision and accuracy, no extra vibration will do good to it. The solution to this issue is:
- Put your 3D printer on a stable surface
- Level your print bed a few times to make sure its accurate
- Implement a BL-touch for auto-levelling
8. Bad Filament Diameter Quality
The poor quality filaments can alter the feeding pressure through the extruder, and this can cause lines to appear on the sides of the 3D print. What you can do is:
- You can buy a filament from a reputable manufacturer or seller.
- You can use a 3D filament guide which can pass through before the extruder.
- Measure the filament diameter and make sure it is within the tolerance
Overall, these are some of the causes which are causing lines to appear on the sides of your 3D print. And I have explained the solutions to how you can avoid or overcome these causes to prevent the lines problem.
9. Start of Layer Position Settings
When I printed benchys, I used to get this vertical seam going straight through the side of it, which didn’t look too pretty.
As I was watching the benchy print, I noticed that each layer started exactly where that vertical seam was.
After some research, I found a simple method to fix this.
- In Cura, check a setting called ‘Z-Seam Alignment’ which you should set to random.
What this setting does it change the starting point of each layer to a random location. Run a test print and hopefully the line in the side of your print should be fixed.
For people struggling with various 3D printing issues, you might want have wanted more guidance towards getting ideal 3D printing results. I created a full course that's available to purchase called Filament Printing 101: Beginner's Guide to Filament Printing that takes you through some of the best 3D printing practices early on, so you can avoid those beginner mistakes.