Hundreds of things can affect the quality of 3D prints, including filament quality, slicing instructions, chamber temperature, nozzle diameters, retraction settings, and even humidity if materials are hygroscopic.
Thankfully, if you know why things are messing up, you can resolve most 3D print quality problems without tearing your hair out. This article on seven common 3D printing problems (with solutions) has you covered.
But what if you want to improve 3D print quality? If it’s general improvements you are looking for, step on up as we deep dive below.
This article provides seven tops for final 3D prints, helping you go from prototype to retail-worthy models in no time.
Let’s jump in!
1. Pick premium materials
There’s no denying the usefulness of economy materials for prototyping, but quality always tells when it comes to final 3D prints.
For example, there is a noticeable difference in quality between Ultimaker PLA and generic PLA – Ultimaker PLA has high crystallinity, making it ideal for overhangs and bridging. In contrast, generic PLA is less stable and prone to imperfections.
The same goes for ABS, PC, PET-G, and other common thermoplastics/polymers. However, the most significant quality differences are when you print thin layers with materials like PET-G, with finer layers showing more imperfections.
Try picking a premium filament brand and see if you can see the difference. And if you already use a premium filament brand, try the ‘plus’ or ‘premium’ version of the filament if it’s available, or switch to another reputable brand.
We have a wide range of high-quality materials from Markforged, Essentium, 3DGence, Ultimaker, and 3CN3D if you want to try a premium brand.
2. Choose your slicer wisely!
CAD and 3D modelling software define your 3D model, but don’t give your 3D printer instructions on how to make it. For this, you need a slicer.
A slicing program creates paths for your 3D printer to follow when printing, allowing it to create your 3D model. However, not all slicers are equal.
Some slicing programs work better with certain 3D printers, and your manufacturer probably has recommendations or proprietary software (e.g., Markforged Eiger).
If your 3D printer is open source, you can use any slicer.
Slicing software translates your 3D model into G-code, an extensive machine language that contains hundreds and sometimes thousands of instructions.
More advanced slicing programs consider GD&T (Geometric Dimensioning and Tolerancing), which produces parts with usability intent parameters.
We recommend using the manufacturer-recommended slicers for the best results. Otherwise, check out SLICER 4.0 (3DGence) and Cura (Ultimaker).
3. Level the bed and set the Z offset
Bed levelling and setting the Z offset (the distance between the nozzle and the bed) are 3D printing basics, yet you’d be surprised by how many pros forget to do it.
While many 3D printers have automatic bed levelling and can position the nozzle automatically, the printer doesn’t always get things right. You might have to manually compensate for an uneven work surface and set it up.
You run the gauge across all four corners and repeat the process three times to ensure that you get the same height for all the corners.
Manual bed levelling requires a feeler gauge or an aluminium card to determine the distance between the nozzle at points across the bed. The feeler gauge will have very little resistance between the bed and nozzle, sliding in and out cleanly.
You will need to adjust the bed levelling whenever you start a new 3D printing session, and interruption to the 3D printing process can also knock things off kilter.
To make things easier, you can also retrofit a bed levelling sensor if your 3D printer hasn’t got one – check out these sensors for ideas.
4. Experiment with print temperatures
If your print temperature is too low or high, you can expect problems with interlayer adhesion, surface quality, and nozzle performance.
For example, stringing is a common issue with high temperatures, caused by plastic oozing from the nozzle and leaving deposits behind.
However, if your nozzle temperature is too low, the most common issue is layer separation – where the layers don’t bond during printing.
Try adjusting the nozzle temperature by plus or minus 1-2°C and see if this helps. Don’t be afraid to experiment with temperatures – thermoplastics can be temperamental, so it isn’t necessarily your printer’s fault for quality issues.
You might also find that a cool or hot chamber can cause problems with print quality, so it’s worth experimenting to find the right configuration.
5. Lower the flow rate for lighter supports (or use breakaway material)
Removing supports from 3D prints can create imperfections in the print surface, damage models irreparably, and create waste.
An easy way to remove supports is to use Ultimaker Breakaway material if you have a dual-extrusion 3D printer.
Alternatively, you can make supports easier to remove by lowering the flow rate, which, if done right, won’t over-compromise the bond between layers (a flow rate that is too low can cause issues with inter-layer adhesion).
Try a flow rate between 80% and 85% for PLA, ABS, and PET-G and between 90% and 95% for nylon and flexible filaments.
The critical thing is to ensure that the bond between layers remains strong so that your models don’t have surface imperfections or structural issues. If you are using rigid plastic, you shouldn’t have issues with strength.
Lighter supports are easier to snap and cut away, and they should be light enough not to impact the layers of the main model structure.
6. Tweak print speed and retraction settings
If your 3D print has noticeable surface imperfections like zits, blobs, dots, and strings, it could be from incorrect speed/retraction settings.
A common cause of stringing and blobs and zits on the print surface is incorrect retraction distance (how much plastic is pulled out of the nozzle) and retraction speed (how fast plastic is retracted from the nozzle) settings.
Check the retraction settings on your 3D printer. The retraction settings are probably too low if you have strings, blobs, or zits. Try increasing the retraction speed and reducing the retraction distance and see if it helps.
Note that it is experimental – you must adjust things by 1mm at a time and strike the right balance. It’s crucial to note that retraction settings are relative to print size and shape complexity – you will need to adjust accordingly.
Your 3D printer might also need retraction calibration, i.e., a grand reset that primes your retraction configuration for future printing. Some 3D printers have autocalibration, but this article will help you do it manually otherwise.
Lastly, keep an eye on print temperatures – excessive melting from too high a temperature can also cause blobs, zits, and stringing. Don’t mistake one problem for the other.
7. Need smooth parts? Post-processing is the answer
Shying away from post-processing in search of golden 3D printer settings is a fool’s errand when your models only need smoothing.
You can quickly smooth parts with chemical vapour technology with AMT PostPro, in which parts are suspended in a chamber and exposed to solvent vapour. The vapour condenses, smoothing the polymers at the surface. Parts are then dried in the chamber, leaving behind a newly smoothed surface akin to injection moulding.
Alternatively, you can post-process your prints with wet and dry sandpaper and get into crevices with a handheld rotary tool. Use mild polish to smooth parts and work to a shine, creating the look of injection-moulded models.
The advantage of vapour smoothing is it eliminates 90% of layer lines and is suitable for FFF, SLS, MJF, and other extrusion-based 3D printer technologies.
Summing up
Improving 3D print quality requires experimentation and practice. While 3D printers get on with the job, and most can auto-calibrate settings, manual intervention is sometimes needed to refine print quality for the best results.
The good news is that 3D printing isn’t rocket science – once you know the terminology and what various 3D printer settings do, you’ll fly.
Need more help?
For expert advice on improving 3D print quality, please get in touch with the team at 01765 694 007, email [email protected], or you can
