3D Printing First Layer Ripples: A Troubleshooting Guide

Whether you’re a 3D printing veteran or not, you’ve probably come across imperfect wavy 3D prints with ripples. There are a couple of causes for first layer rippling issues, the most common being an uneven leveling bed. 

This isn’t always the case however, and in this article we’ll explore all the possible causes to help you get those prints in perfect condition. 

In 3D printing, first layer ripples are usually caused by leaving the layer fan on during the initial phase, a too high printing speed, having the nozzle too close to the print bed, an improper first layer height or flow, and an uneven print bed.

5 Reasons For Ripples in First Layer Of 3D Print

1. Leaving the Layer Fan On

The fan is one of the most easily determined causes of frustrating ripples in your print. Leaving the fan on during the initial layers of print causes adhesion problems. In other words, the filament has a difficult time remaining attached to the printing bed, because of the vibrations coming from the fan. 

To prevent the layer fan from creating ripples on the first layer, you should turn it off during the initial phase of printing. Take note that we’re talking about the model fan and not the fan regulating the nozzle temperature. 

While you think you absolutely have to cool your prints from the start, this isn’t necessary. The filament needs to cool slowly by itself to increase adhesion to the build plate. In fact, you’ll either need very little cooling, or none at all during this stage in the printing. 

2. Too High Printing Speed

As a general rule in the 3D printing scene, slower speeds will create better quality prints. The reason for this rule is that going slow and steady allows the filaments of your print to stick properly to the print bed. 

To determine the importance of going slow, remember how a print is made. The nozzle turns back and forth, all around the printing area to create your model; utilizing force and momentum. If the speed setting is too high, the harder the nozzle stops and goes again in another direction. 

Because of these harsh stops and turns, the initial filaments have less time to fully stick to the print bed; which then causes ripples, or rough surfaces on your model. To be safe, set the first layer speed to 30-50%. 

3. Uneven Bed Leveling

Probably the most common culprit in initial prints is uneven bed leveling. Apart from creating ripples in the first print layers, warped beds can also cause adhesion problems with your filaments; which is an especially widespread problem with the Ender 3 first layer. 

In FDM printers, the nozzle extrudes the filaments layer by layer; therefore you need to have an even print bed so that the filaments layer evenly across the surface. As a matter of fact, It’s regarded that an uneven build plate causes most first layer issues.

Watch out for signs that you have an uneven build plate, such as filaments not sticking to the plate, unevenly extruded from the nozzle, or sporadically distributed all across the surface.

4. Nozzle Too Close to the Printing Bed

Filaments are squeezed out from the nozzle, onto the build plate. Naturally, if the nozzle is too close to the print surface, the filament will be smudged all over the plate, causing ripples or waves. Conversely, if the nozzle is too far from the print surface, the filament won’t attach properly either. 

5. Improper First Layer Height or Flow

To fully explain the influence of flow rate and layer height on ripples, we start by detailing its importance. Flow rate is the amount by which the nozzle extrudes or squeezes out the filaments. 

Over-extrusion of filaments means that your nozzle is releasing too much filament, causing ripples, drips or strings on your model. On the flipside, under-extrusion can lead to holes within the model, missing, or uneven layers. 

On the other hand, the first layer height is the thickness of that first filament layer. We generally recommend a thicker first layer printed for small models. A thick first layer not only disguises any calibration errors, but also increases the first layer’s attachment to the print surface. 

As a rule, you should only either decrease the flow rate, or increase the layer height to compensate. 

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Adjust Settings To Fix Ripples in 3D Printing

Since we’ve listed down the most probable reasons for first layer ripples, it’s time to solve them. To get rid of first layer issues in your prints, you normally have to do a bit of tweaking in your settings. 

Each parameter such as height, filament flow rate, width, speed, fan, and Z offset has a hand in creating first layer ripples, so it only makes sense these settings would have values more optimal than others. Here is a list of the parameters and how to get the best possible performance out of your 3D printer. 

Height and Filament Flow Rate

To avoid both under and over-extrusions, you’ll have to adjust the layer height, nozzle diameter, and printing speed; all of which determine the flow rate. 

The height is generally the thickness of the extruded filament of the first layer. When printing a model with plenty of intricate details, most prefer to have a low layer height because this results in a more detailed product. But a lower layer height can lessen the adhesion of the layer to the build plate, as well as take up more time. 

The suggested initial layer height is slightly higher than the rest of the print. So, if you have a 0.2 mm layer height, increase this to 0.24, or 0.28 mm for the initial layer. 

To compensate for the additional printing time, you could opt for a larger nozzle diameter. Most printers have a default nozzle diameter of 0.4 mm, but you can adjust this up to 1 mm. This increases both the printing speed and layer height. In fact, just adjusting the diameter of the nozzle can hasten printing up to four times faster. 

Different filament materials have different optimal flow rates. Calculate your printer’s flow rate with the formula: Flow Rate (mm^3/s) = (Extrusion Width)(mm) (Layer Height)(mm) (Print Speed) (mm/s). 

The extrusion width in this formula is the nozzle diameter multiplied by 1.2; since the extrusion width should be around 120% of the nozzle diameter. Use the resulting value in the formula and multiply it with the print speed and layer height.

Once you’ve calculated the flow rate, compare it to the ideal flow rate for your filament material and adjust.

Width

Your extruder width should be the same as the one you currently have on your 3D printer. Typically, the width of that is 100% of the nozzle diameter, or just slightly higher. For example, if you have the common nozzle diameter of 0.4 mm, then you should have an extruder with 0.40, 0.44, or even 0.48 mm width. 

A relatively larger extruder width allows more filament material to gush out from the nozzle. Because of the generous material pouring out, the initial layer will be thicker, and more likely to stick to each other and to the bed.

Speed

As we’ve mentioned, a too high printing speed can seriously sacrifice the quality of your prints. The key is to give the extruded filament just enough time to cool and spread on its own, as well as considering the possible jerks of the nozzle. 

It is recommended you set the initial layer speed within 30-50% of the overall movement, so 20-30 mm/s can be a great initial print speed.

This specific setting makes sure that the filament is being squeezed out steadily, with minimal vibrations. This speed also gives the filament enough time to cool. In fact, having a slower initial speed ensures that the first layer adheres to the build surface properly. 

First Layer Fan

In our desire for the first layer filament to cool properly, we often turn the layer fans on. This can create those unsightly first layer ripples. To avoid having uneven cooling and poor layer adhesion, set the fans at 0% for the initial layer. 

Z Offset

In simpler terms, the Z offset is the distance of the nozzle to the build surface initially. Nailing the Z offset can be tricky because you want the nozzle close enough to just ‘squish’ the first layer onto the build plate (thereby increasing adhesion), but not so much. 

To get this measurement right, a rule of thumb is to set the nozzle height at ¼ of your nozzle diameter. So for the 0.4 mm nozzle diameter, the height should be 0.1 mm. To test it out, slip a sheet of A4 paper between the nozzle and the build surface. The paper should slide in and out easily without any snags. 

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Fixing A Flat Printer Bed Problem

In general, a warped 3D printer bed is the most common reason for a rippled first layer. Since the surface isn’t leveled properly, the first layer is unable to adhere well to the build plate. If the printer supports manual leveling, then you need to adjust the screws to get your print bed aligned. 

Installing An Automatic Bed Leveling Sensor

Needless to say, you need a flat printer bed to get high-quality 3D prints every time; and one of the most convenient ways to ensure correct bed leveling is to install an automatic bed leveling sensor. 

We’ve previously established that there is an optimal distance between the nozzle and the printing bed. While you can perform calculations and measurements, an auto bed leveling inductive sensor can make your life heaps easier. 

During the leveling, a sensor probes several points of the bed; thereby gathering data on the distance between it and the nozzle at every turn. During printing, the firmware then uses this data to adjust the nozzle’s Z height to the optimal position automatically. 

This way, the nozzle constantly adjusts as it moves around, ensuring it’s always at a perfect distance from the bed. This mechanism is extremely useful, if the bed is not perfectly leveled. The nozzle will still keep a perfect distance from the printing bed throughout the entire printing process.

Manual Bed Levelling Mesh Procedure

Another type of bed leveling is mesh-based leveling. This type of leveling is a better option for warped beds, or when the edges of the bed are even while the middle area is too near the nozzle. If this is the case with your printer, then tweaking those thumbscrews won’t do you any good. 

Mesh bed leveling is typically applicable for those with firmware for bed leveling such as Marlin Firmware. Instead of having a sensor, the firmware records your Z height settings at several points and builds a mesh. During printing, the firmware then lifts or drops the printhead based on your recorded Z height settings. 

Put simply, the mesh bed leveling begins with the printhead at a certain point in the bed. You slip a single sheet of paper between the printhead and the bed, and the firmware records this height value. The printhead then moves on to a different point in the bed. You repeat the process until you have Z height data for all points of the printing bed. 

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Conclusion

Initial layer ripples can sabotage the quality of any 3D model. These ripples not only affect the appearance, but the structural integrity of your prints as well. In this article we’ve listed down the most common causes for first layer ripples; as well as the best ways for you to avoid them. 

There are other issues with 3D printing, but with proper research and troubleshooting, you can deal with them. It’s always best to identify the root of the problem first before employing any adjustment to your printer settings. This will ensure you don’t create more problems than you’re trying to fix.