3D printer layers not smooth

3D Print Walls Not Smooth – How to Fix – 3D Printerly

Everyone has a time when prints are going perfect, but what about when there are imperfections. I’ve experienced 3D printed walls not being smooth and I’m sure many of you out there have as well, so this article will address how to fix this issue.

The best way to fix 3D printed walls that are not smooth is to identify over-extrusion or under-extrusion issues that you are experiencing and tackle them by changing settings such as retraction or lowering printing temperature. Fixing vibration issues can solve walls that are not smooth.

So, smoothness of a finished product is really important if you want it to stand apart. When it comes to 3D printing and prototyping you would like the same for your printed model.

Sometimes this won’t be easy to achieve. If you are facing this problem with your model, here is everything you need to know to fix it.

There are a number of possible causes that make your walls not smooth. Overall, these will be to do with how your printer is extruding material. All it takes is for one imperfection in a 3D print to ruin the quality of it altogether.

Ghosting/Rippling

When walls aren’t smooth one of the main reasons that people experience is ghosting or rippling. This happens when your printer is moving too fast, at a pace where it can’t handle the vibrations emitted from the fast moving, heavy parts.

Your 3D printer needs to be sturdy and not too heavy in the wrong places to not experience ghosting. I’ve actually written a pretty useful article about How to Fix Ghosting so feel free to check that out.

This visually appears as waves and other irregular patterns formed on the surface of the print ruining its smooth finish.

Vibration of the printer caused by the motor is one of the problems that 3D printer manufacturers put in great effort to solve.

This is why most of the high precision printers weigh a lot. The reason is simple; increasing the stability of the moving parts of the printer can reduce the vibrations.

Adding weights in the right places a moving part can remove instabilities found. These parts are tightly packed into the printer.

Hence, if a part is loose, this can result in vibration. Fastening up the bolts and belts can prevent this issue and replace those that are worn out.

One major thing to consider while printing is to place it on a firm table-top. Wobbly tables can amplify the suppressed vibrations and feed it back into the printer.

If speed is too high for your printer to handle; reduce it to avoid vibrations. Check if the bearings and other moving parts of the printer are functioning smoothly without any jerks.

If that is the issue, you need to lubricate these parts.

Once you have solved this issue, it should stop the imperfection of uneven and wavy lines in your prints that cause walls not to be smooth.

One of the most important factors that determine precision and the quality of a print is the extrusion rate.

For a print to look smooth and fine, it should extrude an adequate amount of material through the nozzle. There are two main types of extrusion issues, over-extrusion and under-extrusion.

I’ll explain both of these types and advise you on how to fix them.

This happens when the printer extrudes more material than what is required. This will result in excess material that can ruin the dimension of the model.

Each layer of the model can be seen separately on the surface projecting as irregular forms. This can be solved within the printing software by adjusting the extrusion rate.

The parameter determining the extrusion rate is extrusion multiplier. Decreasing the extrusion multiplier should resolve this issue.

If the issue still remains, then the problem will be with the extrusion temperature. If the extrusion is too high, it will make the plastic less viscous (it flows more easily) which can lead to over-extrusion.

This can result in plastic beads oozing out from the surface which will destroy its smoothness.

This occurs when the extrusion rate is lower than the required. Lack of material while printing can result in imperfect surfaces with gaps formed between layers.

This can be caused due to the use of filament with wrong diameter. If the diameter of the filament fed into the printer is lower than the expected value, this will cause under-extrusion.

You can prevent this by using filament with the right diameter for printing or this can be rectified with the 3D printer software by increasing the parameter called the extrusion multiplier.

The temperature at which the plastic exits the nozzle and the cooling rate are the two important factors that determines how good a print turns out to be.

Achieving a correct balance between the two factors will provide a print with good finish. The plastic that is printed at the moment is still hot and can form other shapes until it cools.

After cooling it retains to the shape it was printed. If the temperature is too high during the printing time, it will take more time to set.

Without proper cooling, the time to set will be further increased. Hot plastic has a tendency to flow and a longer setting time is sufficient to cause slight deformations.

Most likely, doing this will result in the print model to lose smoothness. It’s seen as more prominent in the case of printing smaller models.

This is because smaller models require less time to print each of its layers, which means that the new layer will print on top of a layer that is not set properly.

Some common solutions to avoid over heating is by decreasing the print temperature, increasing the cooling rate (increase the fan speed) or reducing the printing speed to give it time to set.

Tweak these parameters until you find the perfect conditions to print a model with smooth finish.

If you tried your best and still, there are some slight issues, then the best way is to print many parts at once. This gives other parts time to cool while one part is printed.

Keep in mind, different materials require different levels of cooling and setting times so, if you are changing filament you will have to retest these factors. PLA usually requires a good amount of cooling for smooth walls and high quality.

ABS, on the other hand, reacts quite badly to sharp temperature changes so cooling has to be less significant, along with a fairly constant printing temperature. These settings vary from brand to brand, material to material and even printer to printer.

If you are trying to join two ends of a plastic structure together it is found nearly impossible to do it without leaving any trace.

This is a problem faced by 3D printers too. While printing, the extruder must stop extruding when it moves on the build platform from one position to a new one and start extruding again from that position.

While the extrusion stops and begins, this can cause improper flow rates creating irregular joining and structures at those points.

This is called blobs and zits formation and it can ruin the consistency of the surface. These are usually considered as surface defects as it is caused while printing the outline.

This can be prevented by adjusting the retraction or coasting settings in the 3D printer software. When your retraction settings aren’t set properly, they might take too much plastic away from the print chamber.

After your print tries to re-extrude material, there might be a little bit of a gap between the molten material and the tip of the nozzle. This means the lack of pressure to extrude causes under extrusion and leads to inconsistent flow rates.

A good retraction setting for you to use is 5mm retraction lengths at a speed of 40mm/s.

This is a feature available in some 3D printers only. In this process, slightly heated print head moves over the finished model to warm the plastic and reshape any irregularities present on it producing a smooth surface.

Ironing process can extrude and lay small amounts of plastic on the surface.

10 Ways How to Fix a Poor/Rough Surface Above 3D Print Supports – 3D Printerly

In your 3D printing experience, you might have come across a poor surface just above the supports in your 3D prints. I’ve definitely experienced it, so I set out to find out how exactly to fix this issue.

You should decrease your layer height and nozzle diameter for a better foundation in your supports. Adjust your speed and temperature settings to improve overhang performance, which helps in reducing rough surfaces above supports. Improve your cooling, as well as support roof settings and look towards better part orientation. 

There are many different solutions and in-depth details on how to fix a poor or rough surface above 3D printed supports, so keep reading on to best solve this ongoing issue.

Why Do I Have a Rough Surface Above My Supports?

The usual reason why you have a rough surface above your supports is due to the overhang performance of your 3D printer, or just the way the model is structured in general.

If you have a bad model structure, it’s difficult to reduce rough surfaces above supports because there just isn’t an efficient way to smooth 3D print the object.

If the part orientation is poor, you can definitely discover rough surfaces above support structures.

Overhang performance can definitely help out in terms of this issue because when your layers don’t adhere properly, they can’t produce that smooth surface that you are looking for.

It’s hard to avoid supports for complex models so you just have to make do, however, we can still find ways to make smooth surfaces above supports in one way or another.

In all honesty, with some models you can’t completely cure these rough surfaces but there are techniques and workarounds where you can alter a number of settings, the orientation and much more to solve the issue.

Before we can do this, it’s a good idea to know the direct causes behind why this might happen.

• Layer height too high
• Fast printing speeds
• High temperature settings
• Z-distance setting not adjusted
• Bad model orientation
• Bad support settings
• Low quality filament
• Poor cooling on parts

How Do I Fix a Rough Surface above My Supports?

1.

Lowering your layer height is one of the main fixes that will help fix rough surfaces above your supports. The reason for this is related to the overhang performance, where Your dimensional accuracy increases quite a bit the lower your layer height it, and this directly translates to better overhangs.

Since you are printing more layers, the extruded plastic has more of a foundation to build up from, which is your 3D printer creating smaller steps to create that overhang in the first place.

You want to avoid having to use supports in the first place, but if you do have to implement them, you want to make them as efficient as possible. You want to have support structures for overhangs above that 45° mark, especially at a layer height of 0.2mm

If you use a layer height of 0.1mm, your overhangs can reach further and may even stretch out to that 60° mark.

That’s why I want you to have support structures for any overhang that is above 45 degrees. At this point, you can use a layer height of 0.2mm.

So to achieve better surfaces above your supports:

• Improve your overhang performance to reduce supports
• Use a lower layer height
• Use a smaller nozzle diameter

By doing this, you will be getting different advantages, that are:

• Reducing your print time
• The number of support structures will also be reduced for the print so material is saved
• Achieve a smoother surface on the underside parts.

This is how you can achieve a smooth surface on the parts above supports.

2. Reduce Your Printing Speed

This solution also relates to that overhang performance where you want your layers to adhere to each other as best as they can. When you use fast printing speeds, the extruded material can have a little trouble setting properly.

• Reduce your printing speed in 10mm/s increments until the problem is solved
• You can specifically slow down the speed of the supports rather than all speeds.
• There is ‘Support Speed’ and ‘Support Infill Speed’ which is usually half of your printing speed

This should help out in reduces the rough surfaces above supports by creating a more accurate model according to the dimensions rather than bad printing abilities.

3. Decrease Your Printing Temperature

Depending on whether you have already dialed in your printing temperature, sometimes you might be using a temperature that’s a little too high. If the filament is being melted past the necessary heat levels, it can cause the filament to be more runny.

This can easily result in sagging and drooping while printing those overhangs, which leads to rough surfaces above your support structures.

• Optimize your printing temperature by running a few tests
• Use a temperature low enough to not give under-extrusion and still print consistently.

4. Adjust Support Z-Distance Setting

The right settings can make the world of a difference in your 3D prints. The video below goes through some Cura support settings that you can implement to improve your 3D print quality.

The ‘Support Z-Distance’ setting in Cura is defined as the distance from the top/bottom of the support structure to the print. It’s a gap that provides clearance to remove supports after you have printed your model.

It’s usually at a value which is a multiple of your layer height, where mine is currently showing a multiple of two, which is actually a little much.

• You can narrow down the setting to ‘Support Top Distance’ in Cura and set it to the same as your layer height.
• A multiple of one should produce better surfaces above supports than a multiple of two.

The problem here though, is it may be harder to remove the supports afterwards, since the material can bond like a wall.

5. Split Your Model in Half

Instead of requiring the supports in the first place, you can split your model in half and put the two halves face down on your print bed. After they have printed, you can carefully glue the pieces together to form a nice bond.

Many users choose this option and it works out pretty well, but it works well for some models and not others.

The nature of supports means that you can’t get the same surface quality as the rest of your model because the material can’t be squished down as required to give a smooth surface.

If you manage to slice your model in a certain way, you can reduce the ‘scarring’ or rough surfaces above your supports, by reducing the number of supports and improving the angles that you are printing at.

6. Adjust Support (Infill) Roof Settings

There are a list of settings in Cura which relate to the ‘Roof’ of your supports which is the related to that rough surface above your supports. If you adjust these settings correctly, you can improve the support itself, as well as the surface. Rather than change the setting of the whole support, we can work towards just adjust the settings of the top of the support,

• Do some trial and testing on support roof settings
• ‘Enable Support Roof’ generates a dense slab of material between the top of the model and the support
• Increasing ‘Support Roof Density’ can improve overhang performance and fix those rough surfaces
• If you still notice sagging in the parts above your supports, you can increase it more
• You can also change the ‘Support Roof Pattern’ to Lines (recommended), Grid (default), Triangles, Concentric or Zig Zag
• Adjust the ‘Support Join Distance’ – which is the maximum distance between support structures in the X/Y directions.
• If separate structures are closer together than the set distance, they merge into one support structure. (Default is 2.0mm)

The default Support Roof Density setting in Cura is 33. 33% so you can increase this value and note the changes in performance to see if it helps out. In order to find these settings you can either search it in the search bar, or adjust your Cura view to show ‘Expert’ settings.

7. Use a Second Extruder/Material for Supports (If Available)

Most people don’t have this option, but if you have dual extruders, it can help out greatly when printing with supports. You can 3D print with two different materials, one being the main material for the model, and the other being your support material.

The support material is usually one that can break away easily or even be dissolved in a liquid solution or just plain water. The common example here is 3D printer users 3D printing with PLA and using PVA for supports which is dissolvable in water.

The materials won’t bond together and you’ll have better success printing models with less rough surfaces above the support.

These two materials won’t bond together, and you will get a better chance of printing the material with the less rough surface above supports.

8. Use High Quality Filament

Low quality filament can definitely stunt your printing quality in a way that just works against getting successful prints.

Things like low tolerance accuracy, poor manufacturing methods, moisture absorbed within the filament, dust and other factors can contribute to getting those rough surfaces above supports.

• Start using high quality filament from trusted brand names with many exceptional reviews
• Amazon is a great place to start, but separate retailers like MatterHackers or PrusaFilament have great products
• Order a number of highly rated filaments and find the one which words best for your projects.

9. Improve Your Cooling

When you improve your cooling system, you can improve your overhang performance significantly. What this does is harden your melted plastic a lot quicker, giving it the ability to create a more sturdy foundation and build on top of that.

It may not be perfect, but good cooling can definitely help out with poor surfaces above supports.

• Implement the Petsfang Duct (Thingiverse) on your 3D printer
• Get higher quality fans on your 3D printer

10. Post-Print Work

Most of the solutions here are talking about adjusting the printing process so you no longer get the rough patches on surfaces above supports, but this one is about after the print is finished.

There are methods you can implement to smooth over those rough surfaces so you can have a good-looking 3D print.

• You can sand the surface using high-grit sandpaper and really make that surface smooth, inexpensively.
• If there isn’t much material left to really sand down, you can use a 3D pen to extrude extra filament on the surface
• After the filament has been attached, you can then sand it down to make the model look nice

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