Gaps in 3D prints can cause problems for anyone, from beginners to experts. These gaps can make your print inaccurate, weak and of poor quality.

This article will help you understand why these gaps happen and give you simple solutions to fix them. We'll also share some useful tips to help you fill in layer gaps and get better results every time.

Causes and Fixes of 3D Printing Gaps

Find out what problems can cause gaps in 3D prints and how to fix them.

First Layer Gaps

First layer gaps happen when the nozzle is too far from the bed or the printer isn’t pushing out enough filament. If the nozzle isn’t close enough to the bed, the lines of plastic won’t stick together properly. Clogs in the nozzle or incorrect flow settings can also cause uneven material flow.

To fix this, level the bed carefully or adjust the nozzle height (Z-offset) so it’s slightly closer to the bed. You can also increase the flow rate for the first layer in your slicer or slow down the print speed to give the filament more time to stick.

Related Guide:3D Printing First Layer Problems (Causes and Fixes) 

Top Layer Gaps (Pillowing)

Top layer gaps, also known as "pillowing," happen when the filament doesn't have enough time to solidify before additional layers are laid down. This can occur due to insufficient cooling or an improper layer height.

To address this, ensure your cooling fan is operating at the correct strength, especially when printing slower-moving top layers. If cooling isn't the issue, experiment with lowering the layer height or increasing the number of top solid layers.

For thicker top layers, you may also need to adjust your print speed or increase the layer count, depending on the material used.

For AnkerMake 3D printers users, you can read this guide for more details: How to Fix Top Layer Holes or Gaps

Gaps in Floor Corners

Gaps in floor corners are often caused by more than one thing, like under-extrusion, poor cooling, low infill, high print temperature, or excessive retraction.

First, check the extrusion settings. If under-extrusion is the problem, increase the feed rate or adjust the flow rate in your slicer. If you're not getting enough top layers, try setting the first few layers to at least 1mm thick.

Also, make sure you cool the print properly and adjust the print temperature according to the manufacturer's instructions to help prevent warping. You can also improve corner adhesion and fill the gaps by increasing the infill percentage, lowering the retraction distance, and adjusting the overlap settings.

Gaps Between Thin Walls

Gaps between thin walls often occur when slicer settings aren’t optimized for the printer or filament.

A common fix is increasing the number of perimeters or outlines, which creates stronger side walls and helps eliminate gaps. Additionally, adjusting the extrusion multiplier can boost material flow, reducing the likelihood of gaps.

You can also tweak other settings such as nozzle diameter and extrusion width to fine-tune the print and prevent gaps between thin walls.

For AnkerMake 3D printers users, you can read this guide for more details: How to Fix Gaps in Thin Walls

Gaps Between Lines

Gaps between extrusion lines are a clear sign of under-extrusion. This happens when the printer isn't extruding enough material to fill the space between lines, causing gaps that you can see.

First, check for any blockages in the nozzle or extruder, as these can restrict filament flow. Make sure your nozzle temperature is right for the filament you're using and check the settings for gap filler diameter in your slicer, as gaps that are set wrong can lead to weak lines. If the extruder mechanism itself is malfunctioning, this could also cause insufficient extrusion, so make sure it is functioning correctly.

Gaps Between Infill and Walls

It's common to encounter gaps between the outer walls and the internal infill of your model, which can compromise the structural integrity of the print.

One effective approach is to increase the overlap between the infill and the walls, ensuring that the infill extends slightly into the walls, creating a stronger connection.

In many slicer programs, this setting is referred to as "infill overlap" or "infill/perimeter overlap." By increasing this value, you can reduce or eliminate the gaps between the walls and the infill.

Additionally, make sure that your printer's extrusion settings are properly calibrated. If you don't have enough material being deposited, this can lead to gaps. You can achieve consistent material flow and improve the bond between the walls and the infill by calibrating your extruder and adjusting the extrusion multiplier.

For AnkerMake 3D printers users, you can find detailed settings in this guide: How to Fix Gaps Between infill and walls

Missing or Incomplete Parts

If parts of your model are missing or incomplete, it’s often because of under-extrusion due to improper Z-calibration. When the nozzle is too close to the bed, the extruder can’t deposit enough filament, leading to missing layers. To correct this, recalibrate the Z-axis to ensure the nozzle is at the proper height. Cleaning the nozzle and checking for clogs will also help, as these can contribute to under-extrusion and incomplete parts in your print.

Tips for Filling Layer Gaps in 3D Prints

Discover expert strategies to seamlessly fill layer gaps, enhancing the strength and aesthetics of your 3D prints.

• Monitor Your Printing Speed: Fast printing speed can lead to under-extrusion, which is often a cause of gaps in 3D prints. Lowering the printing speed can ensure that the right amount of filament is directed to the right place, thereby reducing the chances of developing gaps.

• Maintain Nozzle Health: A clogged or unclean nozzle can disrupt proper filament extrusion, leading to random filament distribution and gaps. Regular nozzle maintenance and replacement of damaged ones can help to prevent this issue.

• Regulate Filament Feed Rate: A slow feed rate can prevent sufficient filament from passing through the extruder, resulting in gaps. Maintaining a balanced feed rate is the best way to fill gaps in 3D prints and ensure enough filament is available for accuracy.

• Control Retraction: During non-extrusion movements, the printer pulls the filament back into the nozzle to avoid oozing. If it's retracted too far, it won't be able to push out enough filament, leading to gaps. Managing retraction settings can help to mitigate this problem.

• Boost Bed Adhesion: Poor bed adhesion can cause gaps between layers due to model instability. Improving bed adhesion using adhesives or heating the print bed can reduce this problem.

• Ensure Proper Cooling: Gaps on the top layer, also known as 'pillowing', can occur due to insufficient cooling. Increasing the strength of your cooling fan can help top layers set correctly, thereby reducing gaps.

• Avoid Wet Filament: Moisture within filament can create trapped vapors that cause air bubbles when extruded. This can lead to layer separation and gap formation. Ensure filament is stored correctly to avoid moisture absorption.

For your ultimate 3D experience without gaps, check out these amazing top-notch companions from AnkerMake:

AnkerMake M5 3D Printer

The AnkerMake M5 3D Printer dramatically cuts printing time, revolutionizing the 3D printing experience. Our PowerBoost 2.0 technology ensures smooth power output, increasing power release by 30% compared to its predecessor. This enables the M5 to print at double the speed and acceleration, achieving a fast mode of 500 mm/s, without compromising on quality. With a print volume of 235×235×250 mm³ and precision as fine as 0.1mm, even at 5X speed, the M5 excels in detailed printing. The direct drive extruder and aluminum alloy structure contribute to this precision. Additionally, the M5's intelligent planning and monitoring capabilities help maintain the integrity of prints, effectively preventing and fixing common 3D printing gaps. With the AnkerMake App and Slicer, control is simplified, ensuring prints are accurate, consistent, and match your designs flawlessly, even remotely.

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Wrapping It Up

If you're into 3D printing, it's important to deal with any gaps in the finished product. This can be a bit tricky, but it's worth learning how to fix problems, such as adjusting the printer settings or using special techniques after printing.As you get better at 3D printing, you'll find it more satisfying to fill in these gaps to create the perfect structure you imagined.

To find out more about common 3D Printing problems, read on: 14 Common 3D Printing Problems and Solutions

FAQs about 3D Print Gaps

What is the minimum gap for 3D printing?

The minimum gap for 3D printing primarily depends on material and geometry; however, a general recommendation is to maintain a clearance of approximately 0.3 mm for loose fits and roughly 0.15 mm for tight fits. This ensures a proper fit between the printed parts and optimal functionality.

What causes layer separation in 3d printing?

Layer separation in 3D printing is typically caused by insufficient layer adhesion or temperature discrepancies during the printing process. Factors that contribute to this issue include inadequate heating, improper cooling, insufficient material flow, or inconsistent extrusion rates. To mitigate layer separation, it is essential to maintain appropriate temperature settings, consistent extrusion rates, and proper cooling protocols.