Holes in 3d print

9 Ways How to Fix Holes & Gaps in Top Layers of 3D Prints – 3D Printerly

Having gaps in the top layers of your 3D prints aren’t ideal in any circumstance, but there are solutions which you can try to solve this problem.

The best way to fix gaps in your top layers is to increase the number of top layers in your slicer settings, increase infill percentage, use a denser infill pattern, or look towards fixing under extrusion issues. Sometimes using a default slicer profile works perfectly to fix gaps in top layers.

This article will attempt to guide you through fixing this problem, so keep reading for a detailed solution.

Why Do I Have Holes & Gaps in the Top Layers of my Prints?

Gaps in prints can be a result of several errors related to the printer or the print bed. To identify the origin of the main issue you should consider overviewing some of the main parts of the 3D printer.

Below we have mentioned a few reasons which might be a reason for gaps in your 3D prints as well.

Reasons for gaps in 3D prints may include:

  1. Adjusting number of top layers
  2. Increase infill density
  3. Under-extrusion, over-extrusion and extruder skipping
  4. Fast or slow printing speed
  5. Filament quality and diameter
  6. Mechanical issues with a 3D printer
  7. Clogged or worn out nozzle
  8. Unsteady surface
  9. Unexpected or immediate temperature changes

How to Fix Gaps in the Top Layers of my 3D Prints?

The video explains one side of having gaps in top layers, which is also known as pillowing.

To improve your printer’s performance and the output’s quality, there are several ways you can practice to do so.

Sometimes just using a default profile for your 3D printer works a treat, so definitely try that beforehand. You can also find custom profiles that other people have created online.

Now let’s get into the other solutions that have worked for other 3D printer users.

1. Adjusting Number of Top Layers

This is one effective method of getting rid of gaps in print layers. The solid layer’s extrusions tend to drop and drool in the air pocket because of your partially hollow infill.

The fix is simply changing a setting in your slicer software:

  • Try adding more top solid layers in your slicer
  • A good rule is to go by is to have at least 0.5mm of top layers in your 3D prints.
  • If you have a layer height of 0.1mm, then you should try to have at least 5 top layers to satisfy this guideline
  • Another example would be if you have a layer height of 0.3mm, then use 2 top layers which would be 0.6mm and satisfy the 0.5mm rule.

This is probably the easiest fix in the problem of holes or gaps in your 3D prints since it’s a simple setting change, and it’s very effective in tackling this problem.

If you can see infill through your top layer, then this should help significantly.

2. Increase Infill Density

Another common reason behind having holes and gaps in your 3D prints is using an infill percentage which is too low.

The reason this happens is that your infill kind of acts as supports for the higher parts of your 3D prints.

A low infill percentage would mean less support, or foundation for your material to adhere to, so it can lead to melted plastic drooping which causes those holes or gaps.

  • The simple fix here would be to increase your infill percentage for a better foundation on your 3D prints
  • If you use an infill density of around 20%, I’d try out 35-40% and see how things work out.
  • A setting in Cura called “Gradual Infill Steps” allows you to enable a low infill density at the bottom of your print, while increasing it for the top of the print. Each step you use means that the infill will be halved, so 40% infill with 2 steps goes from at the top 40% to 20% to 10% at the bottom.

3. Under-Extrusion and Extruder Skipping

If you are still experiencing holes or 3D printing gaps between layers or in your top layers, then you probably have under-extrusion issues, which can be caused by a few different issues.

Extrusion issues may include under-extrusion or your extruder clicking which effects the printing badly, and signals some weakness in your extrusion system.

When the amount of filament that your 3D printer thinks is going to be extruded is actually less, this under-extrusion can easily result in missing layers, small layers, gaps within your 3D print, as well as little dots or holes between your layers.

The most common fixes for under-extrusion are:

  • Increase printing temperature
  • Clean nozzle to clear any jams
  • Check that your nozzle isn’t worn out from several hours of 3D printing
  • Use better quality filament with good tolerances
  • Make sure your filament diameter in slicer matches actual diameter
  • Check flow rate and increase your extrusion multiplier (2. 5% increments)
  • Check if the extruder motor is working properly and is provided with enough power or not.
  • Adjust and optimize layer heights for your stepper motor, also called ‘Magic Numbers‘

Check out my article on How to Fix 3D Printer Under-Extrusion – Not Extruding Enough.

Other fixes that could help out in this instance are to make sure your filament feed and extrusion path is smooth and clear. Sometimes having a low quality hotend or nozzle just doesn’t do the best job at melting the filament adequately.

When you upgrade and replace your nozzle, the changes that you can see in 3D print quality can be quite significant, which many people have attested to.

I would also implement Capricorn PTFE tubing for a smoother filament feed into your nozzle.

4. Adjust Printing Speed to be Faster or Slower

Gaps can also occur if your print speed is too high. Due to this, your printer might find it hard to extrude filament in less time.

If your 3D printer is extruding and accelerating at the same time, it can extrude thinner layers, then as it decelerates, extruder normal layers.

To fix this issue, do try the following:

  • Adjust speed by increasing or decreasing the speed by 10mm/s, which can be done specifically just for top layers.
  • Check print speed setting for different factors like walls or infill etc.
  • Check for acceleration settings along with the jerk settings to avoid vibration, then decrease these also
  • 50mm/s is considered a normal speed for your 3D printer

It allows for more cooling which lets your filament harden to form a better foundation for the next layer. You can also print a fan duct to direct cool air straight to your 3D prints.

Check out my article What is the Best Print Speed for 3D Printing? Perfect Settings.

5. Check Filament Quality and Diameter

Incorrect filament diameter can cause printing complications bringing gaps in layers. Ensure your slicer has the ideal filament diameter.

Another reliable method of ensuring this is by measuring the diameter yourself with the help of calipers that you have the correct diameter specified in the software. The most commonly found diameters are 1.75mm and 2.85mm.

The stainless-steel Kynup Digital Calipers is one of the highest rated calipers on Amazon, and for good reason. They are very accurate, up to an accuracy of 0.01mm and very user-friendly.

  • To keep your filament perfect for a long time, read the guide properly.
  • Get a filament from the best manufacturers to avoid headaches of the future.

6. Correct Mechanical Issues with the 3D printer

When it comes to machines, small or big issues may arise. However, the thing is to be aware of how to fix them. Your 3D printer may experience mechanical issues that can bring gaps in the printing. To fix it, try out the following things:

  • Machine oiling is necessary for smoother movements and general maintenance
  • Check if all parts are working properly or not
  • Make sure screws are not loose
  • Z-axis threaded rod should be placed accurately
  • The print bed should be stable
  • Check printer machine connections
  • The nozzle should be tightened correctly
  • Avoid using floating feet


Fix or Replace Clogged/Worn Out Nozzle

The clogged and contaminated nozzle can also significantly bring gaps in 3D Printing. So, check your nozzle and if need be, clean it for better print results.

  • If the nozzle of your printer is worn out, then purchase nozzle from a trusted manufacturer
  • Keep cleaning nozzle with proper instructions as mentioned in the guide.

8. Put Your 3D Printer on Steady Surface

An unstable or vibrating surface cannot bring the perfect print out. This surely can bring gaps in printing if the machine vibrates or is likely to get unstable because of its vibrating surface.

  • Fix this issue by placing the printing machine at a smooth and stable place.

9. Unexpected or Immediate Temperature Changes

Temperature fluctuations can be a great reason for your print to get gaps while printing. This is the most important issue which should be fixed immediately because it decides the flow of plastic as well.

  • Use a brass nozzle as it works best when it comes to thermal conductivity
  • Check if the PID controller is tuned or not
  • Keep checking that temperature should not fluctuate immediately

Check out this video by CHEP for some more helpful tips to fix gaps in your prints.


Gaps between the top layers of 3D print can be a result of various printer’s shortcomings we have mentioned above. There can be more reasons for these gaps, but we have mentioned the major one.

If you figure out the likely root cause, it’ll be easier to solve the error. The main thing is to read the guide thoroughly when you are going to use any printing machine if you want to bring perfection to your work.

How to 3D Print Holes Without Supports – Is it Possible? – 3D Printerly

Many people wonder whether you can 3D print holes without supports since they can either be really hard to remove or result in a hole that has material in the way. This article will take you through some useful tips and advice to create good quality 3D printed holes without supports.

There are definitely some interesting tips that you’ll want to read about so have a read through this article for better details about 3D printing holes without supports.

Can You 3D Print Holes Without Supports?

Yes, you can 3D print holes without supports as long as you have a well-calibrated 3D printer and optimal temperature settings. It can be difficult to get a perfect hole shape in 3D prints due to the layer-by-layer nature of 3D printing, but you can make design adjustments to create better 3D printed holes.

If you’re trying to create complex models with big holes, you might be needing support structures, depending on how well your 3D printer can handle the overhangs of the holes.

Now that you know that the idea is definitely possible, let’s get into the process of 3D printing holes without supports.

How to 3D Print Holes Without Supports

To 3D print holes without supports, try reducing your layer height, use an optimal printing temperature, so the material above the holes don’t sag, use good fan settings with a fan duct to blow cool air on the parts, and design the part with a teardrop shape to create clearance for the top of the hole.

The video below by Maker’s Muse goes through some great design tips that you can implement to 3D print better holes and without supports.

One of the first tips he mentions is how you can create “teardrop” holes rather than circular holes in your 3D models, mainly for horizontally-aligned holes.  

Due to the way 3D printers create objects layer-by-layer, the top of a circle would be a flat layer of extruded material rather than the rounded shape we are looking for, so creating a teardrop hole helps to account for this by adding more of a clearance to the top of the circular hole.

It should reduce the need for you drilling out the hole and removing any flat spots from the surface. The video shows you how this looks in Fusion 360, a CAD software. It’s more important for larger holes and you may be able to get away with not doing this for smaller holes.

The second tip he walks us through is to use a slot to create some movement for the hole to open up and insert your chosen object, which can then be clamped up afterwards. 

He does this by inserting a rectangular part within the circular hole which gives it space to open and close up.

The third tip for designing better 3D printed holes that don’t need supports is similar to the slots, but using “fingers” that are small open spaces just above the holes you want to 3D print.

They allow for the plastic to slightly deform and fit the object you want to put in the hole.

The good thing about this is how it still holds the object tightly since it doesn’t have a lot of space to move around. He mentions that it’s a lot easier to create than it looks, so definitely try it out if you are designing a 3D print with holes in it.

I’d recommend also looking into using good part orientation, or rotating your model sideways so the hole is built up vertically rather than horizontally. Your 3D printer would just be extruding material around the hole, making it a lot easier with gravity working in your favor.

It works best with smaller holes, but can still work well with larger ones.

If you’re an advanced user, it might be worth looking into the following video that talks about 3D printing floating holes without supports.

The idea explained in this video is all about making bridges right below the hole. You can create two rectangular and square-shaped layers before the hole to create a bridge and let them act as support structures for the hole.

This is definitely a complicated technique and only advised for those with fairly decent design skills in software such as AutoCAD or Fusion 360. If you think this is something that you can handle, the video above can surely help you out.

Furthermore, it’s also possible to print holes in 3D prints without supports by changing the shape of the holes.

It’s reported that diamond-shaped holes instead of regular rounded ones in 3D prints can actually give you self-supporting angles. This takes away the need to place support structures around the holes.

Other benefits of using diamond-shaped holes include reducing the print time and the material used, although it will depend on your print for the most part.

You can look into doing this as well, although you will need to design the diamond holes yourself in a CAD software. Again, this is an involved process that does warrant a basic level of design skills.

A unique method that was recently released in Cura is to use a support that extends out from the side, called the “Arch Buttress” under Custom Supports.

The video below by CHEP goes through exactly how to create these supports using a plugin from the Cura Marketplace called Cylindric Custom Support. You can orient your print as normal, then create these supports that can be removed without being troublesome.


This is mainly directed towards filament 3D printing, but if you were to create similar objects with a resin 3D printer, creating holes would be a lot easier since the layer heights are very small.

With a 0.05mm or 50 micron layer height, along with the accuracy of resin printing, creating holes would be more feasible.

How to 3D Print Spheres Without Supports

If you want to 3D print a sphere without supports, consider splitting it into two for the best results. You can use any splitting tool to divide the sphere into two parts.

I really recommend referring to my “How to Split and Cut STL Models for 3D Printing” guide for an in-depth tutorial on how to do that.

After you print the two parts of the sphere together, you will need to attach them together. 10-15 minutes of post-processing will do the trick here.

The following video by My Tech Fun actually talks about a brilliant way of 3D printing spheres and that too without having to use supports.

What you basically do to create some really perfect spheres is to first divide them into two hemispheres and make holes in each hemisphere.

You can then use a set screw that can fit inside the holes painlessly and allow you to screw the two hemispheres together. The best part is that you can 3D print the set screw too in accordance with the diameter of the holes.

However, this is only suitable in cases where it doesn’t matter in what way your sphere can rotate. For example, if you want to print the globe of the earth, the screwing technique might not be very suitable.

Instead, you can use drilling as a technique.

While we’ll get into the process of drilling more in-depth in the next section, it’s worth mentioning here that you can drill four holes in each hemisphere, fill it with glue, and use a piece of filament in each hole to connect the two hemispheres together.

You can see how it’s done in the video above. It’s really an intellectual way of 3D printing spheres without supports.

Can You Drill a Hole in PLA & 3D Prints?

Yes, you can drill a hole in PLA and 3D prints, but you have to be careful not to overdo it and damage the print. ABS can handle being drilled better as it is less brittle than PLA. In addition, it’s better to have holes in your part designed already so they can be drilled easily and give you the best results. 

There are a couple of things to be aware of before getting into drilling PLA and other 3D printer filaments. People often ask the question, “Can you drill a hole into 3D printed plastic?” but the answer isn’t always straightforward.

It’s definitely possible to drill holes in PLA, but you have to make sure not to drill parallel to the layers as it can cause layer-splitting in your parts, which is also known as layer separation. Try drilling perpendicular to the layers for the best results.

Moreover, a firm part is more likely to be drilled nicely as compared to a brittle one. Even if you’re working with PLA, heating it up to about 48-50°C using a hairdryer or anything similar can definitely help.

Another useful tip, in this case, is to place a hard block of something like wood to avoid breaking your part and preventing the drill bit to jam.

Speaking of which, I recommend picking sharp bits over dull ones when drilling 3D printed parts for better performance. There’s definitely a learning curve here that you’ll overcome with experience, but you’ll get there eventually in due time.

The following YouTube video actually shows how to drill 3D printed parts. Do give it a watch for a thorough visual explanation.

How to 3D Print Without Supports

To 3D print without supports, you can lower your layer height, decrease the print speed, and reduce the temperature to achieve better overhang angles, so you won’t need supports. You can also try changing the part orientation to see if it can print without supports. Splitting the print into parts is also favorable.  

3D prints that don’t need supports are usually the best ones because they eliminate a very time-consuming and often harmful-to-the-print part of the post-processing phase.

However, some parts are impossible to create without supports, but you can always implement some techniques to minimize the number of supports used, or remove the need to do so altogether.

One of the first things that you can do to 3D print without supports is to tweak your slicer settings. The following parameters need to be tuned in order to achieve higher overhang angles without needing supports.

  • Layer Height

Generally, a higher layer height, about 0.3mm as opposed to a 0.1 or a 0.2mm layer height will allow your print layers to go longer lengths without being supported.

  • Temperature

As for the temperature, it’s recommended to reduce the extrusion temperature by 5-10°C than what you’re using for the best results. You can either do this or increase the cooling on your part for achieving better overhang angles.

  • Outer Shell Wall Speed

The Outer Shell Wall Speed can be set at somewhere around 5mm/s, so the overhangs can be printed slow and given enough time to cool down, but you can actually keep this setting high by implementing another useful setting, mentioned below.

  • Overhanging Wall Angle
  • Overhanging Wall Speed

These are settings within Cura that allows you to adjust wall speeds only for a specified overhang angle. Cura defaults the Overhang Wall Angle at 90° which is  turned off, while 0° would be every wall being treated as an overhanging wall.

When you lower this angle, it will start reducing your Wall Speed in those angled areas, at a set percentage.

You can find these settings under the “Experimental” tab, or by searching for “Overhanging”.

An example of an Overhanging Wall Angle would be 70° and an Overhanging Wall Speed of 50%, so that any angles that are 70° and above would slow down the print speed by 50%.

One person who made use of this setting mentioned that they had great success with these features for printing unsupported walls at up to 70° without sagging.

Another user mentioned that they had an idea to use an Overhanging Wall Speed above 100% because they had tiny overhangs that would print better at higher speeds, so it can really be used to your advantage as you desire.

The Massive Overhang Test on Thingiverse is a 3D printer calibration test that you can use to really dial in your 3D printer’s settings and print overhangs better, so I’d definitely recommend that for practice and trial and error.

On a side note, check out the 20 Best & Most Popular 3D Printing Calibration Tests to dial-in your printing machine like never before.

The following video by The 3D Print General goes over these slicer settings in detail by utilizing the aforementioned Massive Overhang Test, so check it out for a more visual explanation.

Another point worth noting is that supports connected to the base of the model are relatively easier to deal with as compared to the supports used somewhere on the body of the print.

You can orient your parts in such a way so that their overhangs don’t go very far, like beyond 45°. That way, you would only need to put some supports at the base of the model, which is not only easy to remove but also very doable as a whole.

In addition, if you’re struggling to print parts with supports, you can try searching for their support-free versions online.

The Mandalorian Miniature by Velrock on Thingiverse is a fairly complicated model that requires Cura’s Tree supports to be printed effectively.

Another Thingiverse user called icfirz has actually created a remix of the model and made it support-free, so you really don’t have to trouble yourself with printing supports for The Mandalorian Miniature.

If you’re someone with good design skills, you can actually modify a model in a CAD software like Blender to make it support-free.

If that isn’t a possibility, it’s always worth looking up for any remixes of your specific model to see if anyone has made a version of it that doesn’t need supports.

The following video by Maker’s Muse also goes over some ways of designing 3D prints that don’t need support material.

He talks about using a technique called Sacrificial Bridging. This is when you print a small, yet rigid layer of material beneath the part where support would usually be required thereby forming a solid foundation for the rest of your print.

Although the bridge acts as support, it combines nicely with the rest of the part and doesn’t appear to be a proper support structure. The video above goes more in-depth on this, so do check it out.

Problems, defects, 3D printing errors and solutions

Often during the operation of a 3D printer, problems may arise due to which defects appear on the finished model. Or instead of a neat product, plastic noodles suddenly appear on the table.

In fact, the causes of defects can be conditionally divided into 2 types - these are physical and software.

Physical ones are those that arise due to problems with the mechanics or any other causes that can be eliminated physically. These include problems with printer mechanisms (belt tension, backlash), clogged or deformed nozzle, incorrect table geometry, etc.

Software - these are defects that occur due to incorrect slicer settings or, less often, errors in the printer firmware. For example, incorrectly selected print speed, retract settings, incorrectly selected temperature for plastic, etc.

Very rarely, the problem may lie in the wrong or “flying” printer firmware (although usually the printer simply will not start then), overheating of some boards during printing, etc. These are rather special cases, so we will not consider them.

Model peels off or does not stick to the build plate

This is the most common 3D printing problem. Every 3D printer has had a case when the first layer treacherously rolls, clinging to the extruder, or the most offensive - when it tears off a partially printed model from the table. The first layer must stick tightly otherwise nothing will be printed.

Gap between table and nozzle 9 too large0023

This is the most common reason. You just need to set the correct gap between the table and the nozzle.

Modern printers often use an auto-calibration (auto-leveling) table system or an auxiliary table leveling program. To calibrate such printers, use the instructions. If there is no manual, it can be downloaded from the manufacturer's website.

If you have a simple printer without auto-calibration, a self-assembly or KIT kit, use a probe or a piece of paper folded in half to calibrate. The probe should be slightly pressed against the table by the nozzle. Before calibration, the table and extruder must be heated. Align the table surface over each adjustment screw (there may be 3 or 4) in turn, and only then check the center point.

If you're having trouble getting your table surface perfectly level, try raft printing. Raft is a thick substrate in several layers that is printed under the model. It will help smooth out the slight curvature of the table.

A small cheat sheet to determine the correct gap on the first layer

Plastic with poor adhesion

Some types of plastic, due to various reasons, such as large shrinkage, do not adhere well to the surface of the printing platform. In this case, try using stickers or special 3D adhesives to improve adhesion between the table and the first layer of plastic.

In the early days of 3D printing, there were experiments with different homemade 3D adhesive recipes. ABS diluted in acetone, BF glue, sugar syrup and even beer. Some experiments have been successful. Until now, some enthusiasts use some types of hairspray or glue sticks as 3D glue. But still they are inferior in their properties to industrial 3D adhesives.

Some types of high temperature plastics with a high percentage of shrinkage (ABS, Nylon, etc.) may peel off the table during printing. This is due to uneven cooling and “compression” of the model (the lower layers have already cooled down, but the upper ones have not yet). For such plastics, it is imperative to use a 3D printer with a heated table and a closed case.

Plastic temperature too low

The hotter the plastic is when it exits the nozzle, the better it will adhere to the print bed. It is better to print the first 5-10 layers at a higher temperature (+ 5-10 degrees) and turn off the blower fan.

Wrong first layer settings (speed and thickness)

A thicker layer sticks easier, so the standard first layer is 0.3mm thick. With an increase in print speed, the heating block may simply not have time to heat the plastic to the desired temperature and it will stick to the table worse. Before printing, check the speed and thickness settings of the first layer in the slicer.

A lot depends on how the 3D printer prints the first layer. Try to control the printing of the first layer and only then leave the printer to work alone.

Plastic does not choke from nozzle

The printer has already begun to print, but the print table remains empty. Or part of the model did not print.

Clogged nozzle

In 3D printing, a nozzle is a consumable. The nozzles are clogged or worn out (frequency depends on the type of plastic). The simplest thing is to replace the nozzle. But if there was no spare at hand, you can try to clean the old one. To do this, there is a whole set of thin needles. Or you can heat a clogged nozzle above the melting point of the plastic and “burn out” the blockage. But later it is still better to replace the nozzle.

Low temperature nozzle

You need to increase the temperature of the extruder in the slicer settings or check the thermistor and heating block. Sometimes the thermistor may not read the temperature correctly due to a malfunction or incorrect 3D printer firmware settings.

If the problem occurs after replacing the thermistor - contact the manufacturer or read articles about PID tuning.

Empty extruder

As the extruder heats up, plastic begins to ooze out of the nozzle. Because of this, the extruder may start printing half empty. Because of this, part of the first layer is not printed. You can push the plastic manually by simply pushing the bar into the nozzle. Or solve this problem programmatically - in the slicer, add a contour print around the model (one line).

Some manufacturers and 3D enthusiasts add a line print on the edge of the table at the beginning of each GCode. This is done so that there is plastic in the nozzle by the time the model is printed.

Feed mechanism does not push through plastic

The plastic pushes the feed mechanism to the extruder - a motor with a special pulley put on the shaft. If for some reason the plastic is not pushed through (nozzle clogged, extruder temperature low, etc.), then the pulley “gnaws” through the bar. You need to push the plastic bar with your hands or cut off the damaged piece.

Elephant foot

The first layers of the model are wider and protrude beyond the boundaries of the model. This is due to the fact that the upper layers put pressure on the first ones that have not yet cooled down and flatten them.

High table temperature

Due to the too high temperature of the table, the lower layers remain soft for a long time. Try lowering the table temperature. It is better to reduce gradually (in increments of 5 degrees). You can try to turn on the blower when printing the first layers.

Small gap between nozzle and platen

If, when printing the first layer, the nozzle is too close to the table, then excess plastic will be forced out. After a few coats, this will not be as noticeable, but can lead to the effect of an “elephant's foot”.

Plastic re-extrusion

When too much material is squeezed out of the nozzle, the walls of the model are not smooth, but bumpy, with sagging.

The solution is software - in the settings of the slicer, you need to set the material feed rate (fluidity) to a lower value. The average value is 95-98%.

It is worth checking the diameter of the rod. If its size is greater than 1.75, then the plastic will be squeezed out more than necessary.

Plastic underextrusion

The plastic is squeezed out too little, because of this, gaps may appear between the layer. The finished model will be fragile and fragile.

Wrong thread diameter

Check the filament diameter in the slicer settings. Sometimes, instead of the popular 1.75, the default is 2.85.

Incorrect feed factor settings

Check the fluidity settings in the slicer. The average should be 95-98%.

Clogged nozzle

Something could get into the nozzle and partially block the exit of the plastic. Visually, the plastic will choke from the nozzle, but in a smaller amount than necessary for printing.

Hairiness or cobwebs on finished model

Thin threads of plastic protrude from the outer wall of the model (most often on one side). The defect appears due to the flow of plastic from the nozzle during idle movement.

Insufficient retract

A retract is a slight pull of a plastic filament from an extruder. Due to the retract when the extruder is idle (from layer to layer or from model to model), heated plastic does not drip from the nozzle. For some flowable plastics (eg PETG) the speed and amount of retraction must be increased.

"Hairiness" can be easily removed by grinding or cutting off the threads with a sharp scalpel.

High temperature extruder

The higher the extruder temperature, the more fluid the plastic becomes. It is important to find a balance so that the plastic is not too liquid and sticks well in layers.

In the selection of the optimal extruder temperature, a test model - a tower - helps a lot. It clearly shows how plastic behaves when printed at different temperatures.


Temperature test

Top "perforated" or uneven

The top of the model is bumpy or with holes. The problem may arise if the top of the model is flat. For example, like a cube.

Insufficient airflow

When printing the top plane (cover), the plastic does not have time to cool down and remains too liquid. Because of this, the threads are torn and holes are formed. Increase the fan speed on the last layers.

Few top layers

The top of the print may be too thin and deform as a result. Check slicer settings. The number of upper layers is not recommended to be set less than 6.

Low percentage of filling

If the infill percentage is too low, then the top layer will simply have nothing to rely on. Increase the fill percentage in the slicer settings.

Model deformation

Some parts of the model seem to have melted in some places or on one side. The problem most often occurs when printing with PLA plastic. The defect appears due to the fact that the plastic does not have time to cool and deforms.

Insufficient airflow model

Turn the fans on to maximum. If their power is not enough (in some printers, the fan is located only on one side), you can put a regular desktop fan and direct it to the 3D printer table.

Small model

Small models are difficult to blow well. Try to print small items alongside larger ones, or place several identical models in different corners of the table. So the plastic will have more time to cool.

Layer offset

Layers shift along the x or y axis during printing.

Print head jam

Turn off the printer and try to move the extruder along the x and y axes with your hands. The extruder must move freely. If there are jams, check the mechanics of the printer. Bearing wear or the curvature of the shafts may be to blame.

Electronics overheating

Sometimes electronics problems can be to blame for misaligned layers. The most common cause is overheating of the drivers or too low current exposed to them.

Table top is loose

This is most often seen in 3D printers with glass. During printing, the nozzle may hit the model and move the glass slightly. Before printing, check if the glass or other printing surface is well fixed on the heating table.

Skip layers

Small holes are visible on the print, or the shell of the model is not continuous.

Teflon tube deformed

There are 2 types of thermal barriers - all-metal and with a Teflon tube. If overheated, the Teflon tube may deform. Plastic will pass through it, but in a smaller amount.

Low extruder temperature or high print speed

If the extruder is not heated enough, then the plastic will not be liquid enough and simply will not have time to be forced through the nozzle. The higher the print speed, the higher the extruder temperature should be.

Sometimes the outer walls print well, but the infill is “torn”. In this case, slow down the infill print speed in the slicer.

Model bundle

Cracks form on the surface of the printout during or after printing. Cracks can be large or very small. Most often, this problem occurs with plastics with a high percentage of shrinkage - ABS or Nylon.

Sudden temperature difference (if model delaminates during printing)

With a sharp temperature difference (for example, a draft), part of the model cools down faster. This leads to uneven shrinkage and incorrect distribution of internal stress. For plastics with low shrinkage, this is not critical. But if the shrinkage percentage is more than a few percent, the model may burst in layers.

For printing with such plastics, it is recommended to use a printer with a closed housing. If this is not possible, try to avoid drafts and sudden temperature changes in the room where the 3D printer prints as much as possible.

Print temperature

Due to too low printing temperatures, the layers may not “stick” well to each other. Raise the print temperature in the slicer settings.

Hardening (if the model cracks after printing)

Sometimes cracks appear on the model a few days after printing. This is due to uneven distribution of internal stress after cooling. You can try to “harden” the finished product.

For hardening, the model is placed, for example, in an oven, and heated to the softening temperature of the plastic. After that, the heating is turned off and the oven is left to cool slowly with the model inside. Due to this, the stress inside the print is distributed more evenly. But accuracy is very important in this method - if you make a little mistake with the temperature, the finished product can “float”.


In places where the extruder changed direction, ripples are visible. Most often it looks like a shadow around the “sharp” protruding elements of the model.

Mechanical problems

Sometimes the problem occurs due to extruder play. Check if the extruder mount to the rails is loose. Be sure to check the tension of all belts.

High print speed or high accelerations

Moving the extruder too fast can cause vibrations that cause ripples on the wall of the model. The lighter the weight of the extruder, the less noticeable the ripples will be. To get rid of ringing, simply reduce the print speed in the slicer settings.

Slits for thin-walled models (not solid shell)

The thin wall of the model is not solid, but consists of two thin walls with a narrow gap between them. This problem is often faced by fans of printing "cutting" for baking.

Left model with wall defect, right without

Wall thickness and nozzle diameter mismatch

If the wall thickness is 1 mm, and the nozzle diameter is 0.4, it turns out that for a solid wall, 2 nozzle passes are few, and 3 are already many. The result will depend on the slicer algorithm, but most often you will get 2 walls with a thin slot in the middle (the slicer cannot change the wall thickness). The solution to the problem may be a slight refinement of the 3D model or the use of a different slicer.

Algorithms for calculating 3D models are constantly being improved and refined, and now this problem is less common.

When modeling, take into account not only the thickness of the nozzle, but also the percentage of “overlapping” of lines on each other. If you have a nozzle with a diameter of 0.4 - make the wall in your model not 0. 8, but 0.7 - 0.75.

Wrong model geometry

When instead of a circle you get an oval, and instead of a square you get a semblance of a rhombus.

The main reason is malfunctions in the mechanics of the printer. Be sure to check:


Check belt tension in x and y. Belts stretch over time and may need to be tightened or replaced. Each 3D printer has its own way of tightening the belt. If the belts are slightly stretched, you can tighten them with the help of a "spring".

Loose pulleys, etc.

Check if all bolts and nuts are tight. Are there backlashes. Pay special attention to tightening the pulleys located on the motors along the x and y axes.

Sagging of some parts of the model

Some parts are not printed, broken, or instead of a neat surface, a swollen plastic snot is obtained.

No support for overhangs

A 3D printer cannot print in the air, so if there are overhanging elements in the model, you need to set supports - supports. The slicer can set the necessary support itself, you need to check the appropriate box in the settings.

When printing with soluble support, you can set the gap between the model and support - 0. This will make the surface smoother. If the support material and the model are the same, you need to add a small gap. Otherwise, it will be difficult to separate the support from the model.

Split model

Sometimes the supports can take more plastic than the model. In this case, to save material and time, it will be more convenient to cut the model. If you have more than one 3D printer, then the model will print several times faster.

When cutting the model, you can leave grooves or mortgages so that the pieces of the model are connected without displacement.


In this article, we talked about the most popular 3D printing defects and how to solve them. Don't be intimidated by such a long list. Some problems are rare and you are unlikely to encounter them.

There is a list of problems that arise due to the design features of a 3D printer, so try to choose a printer that suits your needs. To do this, you need to understand what products and what material you need.

Problems associated with printing algorithms are quickly eliminated by software developers.

Do not be afraid of possible difficulties and each print will be successful.

Fixing the 20 Most Common 3D Printing Problems