Ganesh Divte
In traditional FDM 3D printers, the most important part of this technology is the nozzle. It is essentially where the melted filament from the hot end exits in order to form a model, and often it is threaded on one side to connect to the hot end and has a smaller hole on the other side for extruding material.
Without a properly functioning nozzle, print quality will suffer and will lead to a host of other problems. With that being said, not all nozzles are created equal. The type of material it is made out of, the nozzle diameter, and other characteristics have significant influences on its performance and lifespan.
The truth is, nothing lasts forever. While this may sound like a pessimistic outlook, it’s a reality that we must take into account when it comes to printer nozzles. As these components of the printhead assembly become used more and more, they naturally experience wear and tear — an inevitability that can be minimized through regular cleaning and upkeep. Dust, residue from materials printed previously, and other dirt can cause nozzles to degrade faster than they would otherwise.
In this article, we’ll be covering all possible options for cleaning the nozzle regularly and how to prevent practical issues like jamming and overheating, as well as giving you an optimal outcome when printing. so that every reader can pick their preferred method and make sure any printing problems they have stayed firmly in the past!
Recognizing the Issue
It’s important to accurately pinpoint the issue before we jump in and try to resolve it. Before diagnosing a dirty nozzle as the culprit, it’s worth taking time to investigate whether other problems may be causing or contributing to the issue. For each one, we’ve also listed other things to check before deciding that the problem is in the nozzle:
- No first layer: If the first layer looks alright but it seems that no filament is being extruded from your nozzle, it may be easily explained by a clogged nozzle. Before proceeding with the unclogging process, however, double-check that this problem isn’t due to some other issue like a misconfigured extruder, incorrect Z offset settings, or an uneven bed.
- Nozzle picks up printed material: This unique issue occurs when your nozzle lays down material for one layer, then accidentally picks it up again as it moves across the layer, resulting in inconsistencies and wasted filament or resin. Fortunately, this problem is not difficult to identify or fix – in most cases, it is simply due to an improperly aligned nozzle.
- Hot end jam: Hot end jams usually appear to be caused by a filament that is stuck or blocked somewhere in the middle and lower portions of the hot end. This could plausibly mean the nozzle is responsible for a jam, although other parts need to be checked too. The path through which the hot end travels (like the PTFE liner) should be examined as a potential source for the problem.
- Inconsistent extrusion: Inconsistent extrusion can be one of the more complex printer problems to diagnose. It often looks like your printer isn’t able to keep up with the normal rate of material extrusion, resulting in sudden bursts of material. While this may initially lead you to check if the filament is too wet or that the power supply for the extruder’s stepper motor might be an issue, make sure that those are not the root issues before continuing on with other sources.
- Under-extrusion: Under-extrusion is an issue that can be uniquely frustrating. It causes the printer to create a poor result that seems almost random in terms of missing portions of the print. To troubleshoot this problem, there are many factors to consider, such as wet filament, loose extruder tension, or a non-smooth filament path.
- Missing print: If you’re struggling to complete a print, it may be due to a clogged nozzle. But if the nozzle is working correctly and you are still unable to finish printing layers, it’s important to review some other factors. Check that your filament diameter is accurate and that the print temperature is within the specific parameters of the material being printed. Be sure to also rotate the extruder motor even if no filament comes out — this confirms that it’s functioning properly.
As we’ve mentioned earlier, before jumping to more involved fixes, it’s important to first check the nozzle for any possible clogs. Sometimes cleaning it up can do the trick and solve your dilemma. However, depending on what the cause is, that might not fix the situation. So it is best to start by considering each potential source of the problem and checking them one at a time in order from simplest to most complex.
After you have determined that a clogged nozzle is creating issues with your printing, it’s time to move on to the cleaning process. There are many options for approaching this cleaning task, so it’s important to understand which method will work best for your particular model of printer and your specific issue.
Removing External Debris
Debris buildup on the nozzle exterior is a common problem for 3D printers. Often times this is due to the nozzle being too low during the printing of the first layer, resulting in melted material accumulating around it and eventually leading to a clogged nozzle.
This problem is dangerous because the material sticks best to itself and causes a build-up of filaments around the nozzle which can clog it and disrupt subsequent prints. In order to prevent such an inconvenience, it’s important to take good care of your nozzles by regularly inspecting them for dirt or debris accumulation and adjusting their height as often as possible.
Possible Remedies
The easiest way to clean the nozzle is with a damp cloth or an alcohol wipe while the nozzle is still hot – be cautious of some steam being released as you do this. If more intense cleaning is required, delicate wire brushes, small blades, or needles can help coax out any clinging materials that may be clogging up the nozzle. Just ensure you are creating gentle scraping motions when using these tools as too much force can damage the nozzle.
Although it may be possible to clean a nozzle’s exterior, it is always best to take preventative steps in order to ensure that the material does not come into contact with the nozzle in the first place. Certain techniques, such as raising the Z offset and properly levelling the print bed can help reduce contamination. An additional way of keeping the nozzle from becoming contaminated is by using a silicone sock – this covers most of the area around the nozzle and further prevents materials from sticking onto its surface.
Clearing Clogs
Clogs are exceedingly common and incredibly pesky issues, especially in 3D printing. These often occur when debris gets inside the hot end nozzle and causes an obstruction in the output hole. This could mean that you end up with under-extrusion or even missing prints.
There are two forms of nozzle clog: full and partial. While some minor issues related to blockages and obstructions are enough of an annoyance, full clogs are a much more serious problem. A full clog is where the output hole is completely blocked off, trapping filament inside the extruder while preventing it from exiting. In contrast, a partial clog still allows some filament to be pushed out but is cause for concern nonetheless.
Possible Remedies
Luckily, there are several methods for unclogging nozzles – and all are fairly straightforward. Perhaps the easiest is to carefully insert a thin needle into the nozzle opening to break up and push out any debris blocking it.
Alternatively, a cold pull provides an absolutely clean, though needs some added steps for successful execution.
Finally, if you have generic brass nozzles you can replace them completely by heating the hot end and then removing any filament stuck in the extruder.
To do so, heat up the hot end and wait until the old filament can be unscrewed. Once this is done, it is tempting to jump right in and attach the new nozzle; however, it’s important to take extra steps for a successful swap. A small metal rod or pick should be used to clear any leftover filament from inside the assembly before installing the new nozzle
Addressing the PTFE Tube Hot End Gap
There can also be problems if there is a gap between the PTFE tube and the top of the nozzle. This can occur due to an uneven end on the PTFE tube, where it is not pushed down far enough into the hot end, or when the nozzle isn’t screwed in flush with the tube.
When this occurs, any melted filament that goes through this gap in order to reach its destination will cool off inside of it and completely block off your hot end. This issue is common for both all-metal hot ends as well as those with a PTFE lining, so caution should be taken no matter what type of machine you are using!
Possible Remedies
First, the PTFE tube must be removed from the hot end if possible, as nozzles cannot be inserted with the tube in place. The nozzle should then be carefully screwed into the hot end almost 95% of the way in to ensure it is making a tight connection once fully seated. It’s essential to check that the PTFE tube is flat and that its coupler is tightly fastened before inserting it down into the hot end.
The last step involves screwing in the nozzle all the way until it seals properly against the PTFE tube
Replacement and Upgrade Options
If your nozzle is functioning poorly despite your best efforts at cleaning and maintenance, it may be time to invest in a new nozzle. While this can be an inconvenience, it’s important to realize that quality matters when it comes to nozzle performance.
As previously stated, nozzles differ in material, diameter, and other aspects. Depending on the desired print outcome and the material being used, nozzles must be chosen carefully. If a filament containing abrasive particles, such as glow-in-the-dark or wood-filled materials, is used for printing then the durability of the nozzle must be taken into account. Nozzles with low quality may quickly deteriorate when exposed to these types of abrasive materials, reducing the efficiency and accuracy of prints.
It’s essential to consider two important factors when replacing or upgrading your nozzle: diameter and material. The size and type of nozzle you choose will affect not only the precision of your printed object but also the duration of printing, the surface quality of your prints, and even the types of materials you can work with.
Different Nozzle Sizes
0.2 mm
Printing with a 0.2-mm diameter exit hole allows for greater detail and accuracy in your prints. It’s perfect for creating smaller items like miniatures, but it does come with a price: it takes longer to print due to the increased number of print lines and the result is often a weaker material.
0.4 mm
The 0.4-mm diameter has truly become the industry standard for consumer 3D printing, and it’s not hard to see why. This size offers a good balance between print time, the strength of the finished product, and detailed expression.
1.0 mm
If you need to get an object printed out quickly and are willing to sacrifice some detail in the print, this diameter nozzle is the right choice for you. It’s one of the larger nozzles available, so prints can be produced much faster than with smaller ones. The fewer lines in the print also make it far sturdier and more capable of maintaining its shape throughout usage.
Various Nozzle Materials
Brass
If affordability is your number one priority when looking to purchase nozzles, then brass is your best choice. Not only is brass the most popular material for nozzles, but you can buy 25 generic ones for less than $10 – making them one of the most budget-friendly options on the market. Though they might be cheap, their lifespan won’t last as long as other materials – at least when used with abrasive materials such as nylon and PVA. Fortunately, brass nozzles will remain in great condition when used with non-abrasive materials like PLA, ABS and PETG.
Steel
Steel nozzles are a superior choice to brass nozzles when it comes to long-term and multi-purpose use. They may cost slightly more upfront, but the benefits they provide are too good to ignore. As strong and tensile as they are resistant to corrosion, these nozzles can handle temperatures far in excess of what their brass counterparts can withstand. Furthermore, steel nozzles also offer an added layer of protection against abrasive materials; while heavier use of these materials will eventually degrade the nozzle, light use should pose little threat.
- Approximate price per nozzle: $0.70-$20
- Popular brands: E3D, Creality, Micro Swiss, Afunta
Ruby-tipped
Ruby nozzles are a remarkable and well-respected product in the nozzle industry. Crafted with brass as its base and a ruby tip, they offer immense resilience and long-lasting use. Pressure washers, laser and water jet cutters, and industrial cleaners all rely on ruby nozzles for their most powerful applications. Ruby is a hard and durable gemstone which also makes it costly, making these nozzles quite an investment at around $100 per piece.
- Approximate price per nozzle: $90-$100
- Popular brands: Olsson Ruby
Ganesh Divte
I am Ganesh Divte. I work as a Quality Assurance Engineer at Dhruvtara WireTech PVT LTD. I have experience in SLS, DMSL, FDM, and SLA additive manufacturing processes. I am very enthusiastic about additive manufacturing and its potential to change the way we manufacture products. I believe that Additive Manufacturing has the potential to revolutionize the manufacturing industry and make it more efficient and sustainable.
