What Causes First Layer Ripples on 3D Printed Models?

While only a tiny part of the printing process in terms of the time going into it, it’s undeniable that the first layer of a 3D printed model essentially determines the success of the print as it acts as the foundation of the model.

As printing the first layer of the print is a slightly different process than the rest of it due to the layer coming into direct contact with the build plate, first layer problems can become particularly cumbersome at times and require a decent amount of effort and time to solve.

Today, we will be focusing on the specific issue of ripples appearing on the first layer of a 3D printed model, which is one of the most commonly encountered first layer problems in the 3D printing realm.

So, what causes first layer ripples on 3D printed models?

First layer ripples on 3D printed models can appear due to a few different factors, which we have listed below:

  • First layer height too low
  • Build plate (printer bed) not level
  • Z offset too low
  • Print speed too high
  • Cooling fan speed too high
  • Flow rate too high

Moving forward, we will analyze the issue of first layer ripples in greater detail, discuss what you can do to fix it, and look at the signs that the problem brings to make it easier to identify.

What Causes First Layer Ripples on 3D Printed Models?

Unfortunately, the issue of first layer ripples is one of the trickier things in 3D printing, as there are many factors that can contribute to its appearance.

First Layer Height Too Low

A first layer height value that is way too low is one of the most likely culprits for the issue of first layer ripples.

When the height of the first layer is way too low, the amount of plastic that comes out of the nozzle will be way too much for the space that needs to accommodate it (as the gap between the nozzle and the build plate won’t be large enough), causing ripples as a result.

In the case of a too low first layer height, you will most likely observe ripples throughout the entire first layer due to the printhead never having enough space to perform a clean extrusion.

Alongside ripples, a first layer height that is too low will often cause issues such as:

  • Clogging of the hotend due to the filament gathering on the nozzle
  • Elephant’s foot due to layers becoming squished on top of each other
  • Incorrect model thickness due to the excess filament that keeps piling up
  • Bad surface quality due to the hotend dragging through the layers

Build Plate (Printer Bed) Not Level

Another very likely culprit behind the appearance of first layer ripples is a build plate that isn’t level.

A build plate that isn’t level will cause the space between the build plate and the hotend to be way too tight for some areas of the model, causing ripples due to the amount of plastic being more exceeding than the tight spaces can accommodate.

In the case of a build plate that isn’t level, you will most likely observe ripples in some areas of the first layer, as the area where the build plate is tilted upwards will reduce the space between itself and the nozzle.

Aside from the ripples, a build plate that isn’t level will bring issues such as:

  • Bed adhesion issues due to the filament not sticking to the build plate evenly
  • Inconsistent print lines due to the variance of space among different areas
  • Hotend clogging due to the plastic not being able to leave the nozzle
  • Gaps and holes on the first layer of the print due to the space inconsistencies

Z Offset Too Low

While less common, a lower than optimal Z-offset value creates a very similar effect to the problem of the first layer height being too low.

Just as a too low first layer height value, a Z-offset value that is lower than optimal will cause the space between the nozzle and the printer bed to be too small, causing the plastic not to have enough room to settle cleanly.

With a Z-offset value that is too low, you should observe ripples throughout the entire layer due to the low Z-offset reducing the space between the nozzle and the build plate for the entirety of the area.

With a too low Z-offset value, you will most likely also observe signs such as:

  • Print lines become too flat
  • Peaks and valleys on the first layer
  • Inconsistencies on the first layer, such as some parts not being printed at all
  • Plastic sticks too strongly to the build plate

Print Speed Too High

A print speed that is too high is known to create a large set of problems, and the issue of ripples on the first layer is one of them.

When the first layer print speed value is too high, inconsistencies can appear on the first layer due to the nozzle dragging the plastic around while it moves at high speeds, sometimes presenting itself in the form of ripples.

With a first layer print speed value that is too high, you will most likely observe inconsistent ripples scattered around the model randomly as the printhead won’t always be dragging the plastic.

Alongside ripples, you can also observe the following signs if the first layer print speed is too high:

  • Poor bed adhesion
  • Low first layer quality

Cooling Fan Speed Too High

Cooling is usually a tricky subject, as the amount of cooling the first layer requires is often different than the rest of the print.

Cooling the first layer down too quickly prevents the plastic from settling as consistently as possible, and the inconsistency can sometimes present itself in the form of ripples.

With a cooling fan speed value that is too high, you should expect inconsistent rippling on some areas of the first layer that has cooled down quicker than it should have.

Below are some of the other signs that you can observe due to cooling being too quick:

  • Weak bed adhesion
  • Inconsistent first layer

Flow Rate (Extrusion Multiplier) Too High

While flow rate isn’t a value that sees change often, it could also contribute to the issue of first layer ripples in some cases.

A flow rate that is too high will cause the printer to extrude way more plastic that can fit in the space between the nozzle and the build plate. As a result of this, ripples will appear throughout the first layer due to the excess plastic.

With a flow rate that is too high, you should be observing a consistent rippling pattern due to the plastic being excess for all areas of the first layer.

That being said, a misconfigured flow rate value will create more pressing over-extrusion related issues than merely first layer rippling, such as:

  • Stringing
  • Blobbing
  • Inconsistencies in dimensions
  • Deformation of the printed model
  • Poor surface quality

How to Fix First Layer Ripples on 3D Printed Models?

As there are many factors that can cause first layer ripples to appear, fixing the issue requires a lot of time and effort spent on trial and error until you find the correct solution.

To fix the issue of first layer ripples on your 3D printed model, we recommend following the steps below in order and running a test print after each step to check whether the problem has been resolved or not:

  1. Increase the first layer height. Increasing the first layer height is the first thing you should do, as a small layer height is the most common culprit behind ripples. While the optimal initial layer height depends on the filament type, we can recommend incrementally increasing the value and running a series of test prints.
  2. Level the build plate. Ensuring the build plate is level is just as important as using an optimal first layer height value. While we recommend using an auto bed leveling sensor, such as BLTouch, to ensure that the build plate is level at all times, you can also use the paper method to reliably level the bed if you don’t have access to a sensor.
  3. Increase the Z-offset value. Whenever you home the printer, the printhead should be very close to, but not touching the build plate, with a distance of paper thickness separating the two. If this is not the case, slightly increasing the Z offset be helpful to solve the problem.
  4. Decrease the first layer print speed. As a rule of thumb, it’s a good idea to set the first layer print speed to a value that falls between 30%-50% of the overall print speed for the first layer to print healthily.
  5. Decrease the first layer cooling fan speed. Just as the first layer print speed, the first layer cooling fan speed should also be low compared to the fan speed for the rest of the print. With some filament types, such as PETG, you can even turn the cooling fans off for the first layer.
  6. Decrease the first layer flow rate (extrusion multiplier). While you most likely shouldn’t modify the flow rate value unless you’re having issues with over-extrusion throughout the whole print, slight adjustments to this parameter can be helpful to resolve the issue of ripples.

As these steps cover every factor that can cause the issue of first layer ripples, carefully going through each of them should most likely solve the problem.

How to Identify First Layer Ripples on 3D Printed Models?

Identifying whether the issue you’re facing is first layer ripples or something else is vital to the process of solving it, as knowing what you’re dealing with is half of the battle.

The primary characteristic of first layer ripples is the appearance of wrinkles, waves, and bumps on the first layer of your 3D printed model, essentially causing the first layer to become uneven instead of a smooth surface.

Depending on the severity of the situation, the ripples can show up throughout the entirety of the layer or only in certain parts, which gives us more insight into what causes the issue.

Wrapping Up

Just as with many other first-layer problems, solving the issue of first-layer ripples can also become quite annoying due to the many factors that can cause it.

To quickly recap, let’s go over the factors that can cause first layer ripples on 3D printed models once again:

  • First layer height higher than optimal
  • Uneven print bed
  • Too low of a Z-offset value
  • Too high extrusion multiplier
  • Printing the first layer too quickly
  • Too much cooling on the first layer

While pinpointing the root cause and fixing it is the quickest solution, it’s not a bad idea to go over each of these factors individually and ensure that you correctly configure them either to ensure that you don’t overlook anything.

Happy printing!